text: // https://d3js.org v5.16.0 Copyright 2020 Mike Bostock
  (function (global, factory) {
      typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
              typeof define === 'function' && define.amd ? define(['exports'], factory) :
              (global = global || self, factory(global.d3 = global.d3 || {}));
  }(this, function (exports) {
      'use strict';
  
      var version = "5.16.0";
  
      function ascending(a, b) {
          return a < b ? -1 : a > b ? 1 : a >= b ? 0 : NaN;
      }
  
      function bisector(compare) {
          if (compare.length === 1)
              compare = ascendingComparator(compare);
          return {
              left: function (a, x, lo, hi) {
                  if (lo == null)
                      lo = 0;
                  if (hi == null)
                      hi = a.length;
                  while (lo < hi) {
                      var mid = lo + hi >>> 1;
                      if (compare(a[mid], x) < 0)
                          lo = mid + 1;
                      else
                          hi = mid;
                  }
                  return lo;
              },
              right: function (a, x, lo, hi) {
                  if (lo == null)
                      lo = 0;
                  if (hi == null)
                      hi = a.length;
                  while (lo < hi) {
                      var mid = lo + hi >>> 1;
                      if (compare(a[mid], x) > 0)
                          hi = mid;
                      else
                          lo = mid + 1;
                  }
                  return lo;
              }
          };
      }
  
      function ascendingComparator(f) {
          return function (d, x) {
              return ascending(f(d), x);
          };
      }
  
      var ascendingBisect = bisector(ascending);
      var bisectRight = ascendingBisect.right;
      var bisectLeft = ascendingBisect.left;
  
      function pairs(array, f) {
          if (f == null)
              f = pair;
          var i = 0, n = array.length - 1, p = array[0], pairs = new Array(n < 0 ? 0 : n);
          while (i < n)
              pairs[i] = f(p, p = array[++i]);
          return pairs;
      }
  
      function pair(a, b) {
          return [a, b];
      }
  
      function cross(values0, values1, reduce) {
          var n0 = values0.length,
                  n1 = values1.length,
                  values = new Array(n0 * n1),
                  i0,
                  i1,
                  i,
                  value0;
  
          if (reduce == null)
              reduce = pair;
  
          for (i0 = i = 0; i0 < n0; ++i0) {
              for (value0 = values0[i0], i1 = 0; i1 < n1; ++i1, ++i) {
                  values[i] = reduce(value0, values1[i1]);
              }
          }
  
          return values;
      }
  
      function descending(a, b) {
          return b < a ? -1 : b > a ? 1 : b >= a ? 0 : NaN;
      }
  
      function number(x) {
          return x === null ? NaN : +x;
      }
  
      function variance(values, valueof) {
          var n = values.length,
                  m = 0,
                  i = -1,
                  mean = 0,
                  value,
                  delta,
                  sum = 0;
  
          if (valueof == null) {
              while (++i < n) {
                  if (!isNaN(value = number(values[i]))) {
                      delta = value - mean;
                      mean += delta / ++m;
                      sum += delta * (value - mean);
                  }
              }
          } else {
              while (++i < n) {
                  if (!isNaN(value = number(valueof(values[i], i, values)))) {
                      delta = value - mean;
                      mean += delta / ++m;
                      sum += delta * (value - mean);
                  }
              }
          }
  
          if (m > 1)
              return sum / (m - 1);
      }
  
      function deviation(array, f) {
          var v = variance(array, f);
          return v ? Math.sqrt(v) : v;
      }
  
      function extent(values, valueof) {
          var n = values.length,
                  i = -1,
                  value,
                  min,
                  max;
  
          if (valueof == null) {
              while (++i < n) { // Find the first comparable value.
                  if ((value = values[i]) != null && value >= value) {
                      min = max = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = values[i]) != null) {
                              if (min > value)
                                  min = value;
                              if (max < value)
                                  max = value;
                          }
                      }
                  }
              }
          } else {
              while (++i < n) { // Find the first comparable value.
                  if ((value = valueof(values[i], i, values)) != null && value >= value) {
                      min = max = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = valueof(values[i], i, values)) != null) {
                              if (min > value)
                                  min = value;
                              if (max < value)
                                  max = value;
                          }
                      }
                  }
              }
          }
  
          return [min, max];
      }
  
      var array = Array.prototype;
  
      var slice = array.slice;
      var map = array.map;
  
      function constant(x) {
          return function () {
              return x;
          };
      }
  
      function identity(x) {
          return x;
      }
  
      function sequence(start, stop, step) {
          start = +start, stop = +stop, step = (n = arguments.length) < 2 ? (stop = start, start = 0, 1) : n < 3 ? 1 : +step;
  
          var i = -1,
                  n = Math.max(0, Math.ceil((stop - start) / step)) | 0,
                  range = new Array(n);
  
          while (++i < n) {
              range[i] = start + i * step;
          }
  
          return range;
      }
  
      var e10 = Math.sqrt(50),
              e5 = Math.sqrt(10),
              e2 = Math.sqrt(2);
  
      function ticks(start, stop, count) {
          var reverse,
                  i = -1,
                  n,
                  ticks,
                  step;
  
          stop = +stop, start = +start, count = +count;
          if (start === stop && count > 0)
              return [start];
          if (reverse = stop < start)
              n = start, start = stop, stop = n;
          if ((step = tickIncrement(start, stop, count)) === 0 || !isFinite(step))
              return [];
  
          if (step > 0) {
              start = Math.ceil(start / step);
              stop = Math.floor(stop / step);
              ticks = new Array(n = Math.ceil(stop - start + 1));
              while (++i < n)
                  ticks[i] = (start + i) * step;
          } else {
              start = Math.floor(start * step);
              stop = Math.ceil(stop * step);
              ticks = new Array(n = Math.ceil(start - stop + 1));
              while (++i < n)
                  ticks[i] = (start - i) / step;
          }
  
          if (reverse)
              ticks.reverse();
  
          return ticks;
      }
  
      function tickIncrement(start, stop, count) {
          var step = (stop - start) / Math.max(0, count),
                  power = Math.floor(Math.log(step) / Math.LN10),
                  error = step / Math.pow(10, power);
          return power >= 0
                  ? (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1) * Math.pow(10, power)
                  : -Math.pow(10, -power) / (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1);
      }
  
      function tickStep(start, stop, count) {
          var step0 = Math.abs(stop - start) / Math.max(0, count),
                  step1 = Math.pow(10, Math.floor(Math.log(step0) / Math.LN10)),
                  error = step0 / step1;
          if (error >= e10)
              step1 *= 10;
          else if (error >= e5)
              step1 *= 5;
          else if (error >= e2)
              step1 *= 2;
          return stop < start ? -step1 : step1;
      }
  
      function thresholdSturges(values) {
          return Math.ceil(Math.log(values.length) / Math.LN2) + 1;
      }
  
      function histogram() {
          var value = identity,
                  domain = extent,
                  threshold = thresholdSturges;
  
          function histogram(data) {
              var i,
                      n = data.length,
                      x,
                      values = new Array(n);
  
              for (i = 0; i < n; ++i) {
                  values[i] = value(data[i], i, data);
              }
  
              var xz = domain(values),
                      x0 = xz[0],
                      x1 = xz[1],
                      tz = threshold(values, x0, x1);
  
              // Convert number of thresholds into uniform thresholds.
              if (!Array.isArray(tz)) {
                  tz = tickStep(x0, x1, tz);
                  tz = sequence(Math.ceil(x0 / tz) * tz, x1, tz); // exclusive
              }
  
              // Remove any thresholds outside the domain.
              var m = tz.length;
              while (tz[0] <= x0)
                  tz.shift(), --m;
              while (tz[m - 1] > x1)
                  tz.pop(), --m;
  
              var bins = new Array(m + 1),
                      bin;
  
              // Initialize bins.
              for (i = 0; i <= m; ++i) {
                  bin = bins[i] = [];
                  bin.x0 = i > 0 ? tz[i - 1] : x0;
                  bin.x1 = i < m ? tz[i] : x1;
              }
  
              // Assign data to bins by value, ignoring any outside the domain.
              for (i = 0; i < n; ++i) {
                  x = values[i];
                  if (x0 <= x && x <= x1) {
                      bins[bisectRight(tz, x, 0, m)].push(data[i]);
                  }
              }
  
              return bins;
          }
  
          histogram.value = function (_) {
              return arguments.length ? (value = typeof _ === "function" ? _ : constant(_), histogram) : value;
          };
  
          histogram.domain = function (_) {
              return arguments.length ? (domain = typeof _ === "function" ? _ : constant([_[0], _[1]]), histogram) : domain;
          };
  
          histogram.thresholds = function (_) {
              return arguments.length ? (threshold = typeof _ === "function" ? _ : Array.isArray(_) ? constant(slice.call(_)) : constant(_), histogram) : threshold;
          };
  
          return histogram;
      }
  
      function threshold(values, p, valueof) {
          if (valueof == null)
              valueof = number;
          if (!(n = values.length))
              return;
          if ((p = +p) <= 0 || n < 2)
              return +valueof(values[0], 0, values);
          if (p >= 1)
              return +valueof(values[n - 1], n - 1, values);
          var n,
                  i = (n - 1) * p,
                  i0 = Math.floor(i),
                  value0 = +valueof(values[i0], i0, values),
                  value1 = +valueof(values[i0 + 1], i0 + 1, values);
          return value0 + (value1 - value0) * (i - i0);
      }
  
      function freedmanDiaconis(values, min, max) {
          values = map.call(values, number).sort(ascending);
          return Math.ceil((max - min) / (2 * (threshold(values, 0.75) - threshold(values, 0.25)) * Math.pow(values.length, -1 / 3)));
      }
  
      function scott(values, min, max) {
          return Math.ceil((max - min) / (3.5 * deviation(values) * Math.pow(values.length, -1 / 3)));
      }
  
      function max(values, valueof) {
          var n = values.length,
                  i = -1,
                  value,
                  max;
  
          if (valueof == null) {
              while (++i < n) { // Find the first comparable value.
                  if ((value = values[i]) != null && value >= value) {
                      max = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = values[i]) != null && value > max) {
                              max = value;
                          }
                      }
                  }
              }
          } else {
              while (++i < n) { // Find the first comparable value.
                  if ((value = valueof(values[i], i, values)) != null && value >= value) {
                      max = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = valueof(values[i], i, values)) != null && value > max) {
                              max = value;
                          }
                      }
                  }
              }
          }
  
          return max;
      }
  
      function mean(values, valueof) {
          var n = values.length,
                  m = n,
                  i = -1,
                  value,
                  sum = 0;
  
          if (valueof == null) {
              while (++i < n) {
                  if (!isNaN(value = number(values[i])))
                      sum += value;
                  else
                      --m;
              }
          } else {
              while (++i < n) {
                  if (!isNaN(value = number(valueof(values[i], i, values))))
                      sum += value;
                  else
                      --m;
              }
          }
  
          if (m)
              return sum / m;
      }
  
      function median(values, valueof) {
          var n = values.length,
                  i = -1,
                  value,
                  numbers = [];
  
          if (valueof == null) {
              while (++i < n) {
                  if (!isNaN(value = number(values[i]))) {
                      numbers.push(value);
                  }
              }
          } else {
              while (++i < n) {
                  if (!isNaN(value = number(valueof(values[i], i, values)))) {
                      numbers.push(value);
                  }
              }
          }
  
          return threshold(numbers.sort(ascending), 0.5);
      }
  
      function merge(arrays) {
          var n = arrays.length,
                  m,
                  i = -1,
                  j = 0,
                  merged,
                  array;
  
          while (++i < n)
              j += arrays[i].length;
          merged = new Array(j);
  
          while (--n >= 0) {
              array = arrays[n];
              m = array.length;
              while (--m >= 0) {
                  merged[--j] = array[m];
              }
          }
  
          return merged;
      }
  
      function min(values, valueof) {
          var n = values.length,
                  i = -1,
                  value,
                  min;
  
          if (valueof == null) {
              while (++i < n) { // Find the first comparable value.
                  if ((value = values[i]) != null && value >= value) {
                      min = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = values[i]) != null && min > value) {
                              min = value;
                          }
                      }
                  }
              }
          } else {
              while (++i < n) { // Find the first comparable value.
                  if ((value = valueof(values[i], i, values)) != null && value >= value) {
                      min = value;
                      while (++i < n) { // Compare the remaining values.
                          if ((value = valueof(values[i], i, values)) != null && min > value) {
                              min = value;
                          }
                      }
                  }
              }
          }
  
          return min;
      }
  
      function permute(array, indexes) {
          var i = indexes.length, permutes = new Array(i);
          while (i--)
              permutes[i] = array[indexes[i]];
          return permutes;
      }
  
      function scan(values, compare) {
          if (!(n = values.length))
              return;
          var n,
                  i = 0,
                  j = 0,
                  xi,
                  xj = values[j];
  
          if (compare == null)
              compare = ascending;
  
          while (++i < n) {
              if (compare(xi = values[i], xj) < 0 || compare(xj, xj) !== 0) {
                  xj = xi, j = i;
              }
          }
  
          if (compare(xj, xj) === 0)
              return j;
      }
  
      function shuffle(array, i0, i1) {
          var m = (i1 == null ? array.length : i1) - (i0 = i0 == null ? 0 : +i0),
                  t,
                  i;
  
          while (m) {
              i = Math.random() * m-- | 0;
              t = array[m + i0];
              array[m + i0] = array[i + i0];
              array[i + i0] = t;
          }
  
          return array;
      }
  
      function sum(values, valueof) {
          var n = values.length,
                  i = -1,
                  value,
                  sum = 0;
  
          if (valueof == null) {
              while (++i < n) {
                  if (value = +values[i])
                      sum += value; // Note: zero and null are equivalent.
              }
          } else {
              while (++i < n) {
                  if (value = +valueof(values[i], i, values))
                      sum += value;
              }
          }
  
          return sum;
      }
  
      function transpose(matrix) {
          if (!(n = matrix.length))
              return [];
          for (var i = -1, m = min(matrix, length), transpose = new Array(m); ++i < m; ) {
              for (var j = -1, n, row = transpose[i] = new Array(n); ++j < n; ) {
                  row[j] = matrix[j][i];
              }
          }
          return transpose;
      }
  
      function length(d) {
          return d.length;
      }
  
      function zip() {
          return transpose(arguments);
      }
  
      var slice$1 = Array.prototype.slice;
  
      function identity$1(x) {
          return x;
      }
  
      var top = 1,
              right = 2,
              bottom = 3,
              left = 4,
              epsilon = 1e-6;
  
      function translateX(x) {
          return "translate(" + (x + 0.5) + ",0)";
      }
  
      function translateY(y) {
          return "translate(0," + (y + 0.5) + ")";
      }
  
      function number$1(scale) {
          return function (d) {
              return +scale(d);
          };
      }
  
      function center(scale) {
          var offset = Math.max(0, scale.bandwidth() - 1) / 2; // Adjust for 0.5px offset.
          if (scale.round())
              offset = Math.round(offset);
          return function (d) {
              return +scale(d) + offset;
          };
      }
  
      function entering() {
          return !this.__axis;
      }
  
      function axis(orient, scale) {
          var tickArguments = [],
                  tickValues = null,
                  tickFormat = null,
                  tickSizeInner = 6,
                  tickSizeOuter = 6,
                  tickPadding = 3,
                  k = orient === top || orient === left ? -1 : 1,
                  x = orient === left || orient === right ? "x" : "y",
                  transform = orient === top || orient === bottom ? translateX : translateY;
  
          function axis(context) {
              var values = tickValues == null ? (scale.ticks ? scale.ticks.apply(scale, tickArguments) : scale.domain()) : tickValues,
                      format = tickFormat == null ? (scale.tickFormat ? scale.tickFormat.apply(scale, tickArguments) : identity$1) : tickFormat,
                      spacing = Math.max(tickSizeInner, 0) + tickPadding,
                      range = scale.range(),
                      range0 = +range[0] + 0.5,
                      range1 = +range[range.length - 1] + 0.5,
                      position = (scale.bandwidth ? center : number$1)(scale.copy()),
                      selection = context.selection ? context.selection() : context,
                      path = selection.selectAll(".domain").data([null]),
                      tick = selection.selectAll(".tick").data(values, scale).order(),
                      tickExit = tick.exit(),
                      tickEnter = tick.enter().append("g").attr("class", "tick"),
                      line = tick.select("line"),
                      text = tick.select("text");
  
              path = path.merge(path.enter().insert("path", ".tick")
                      .attr("class", "domain")
                      .attr("stroke", "currentColor"));
  
              tick = tick.merge(tickEnter);
  
              line = line.merge(tickEnter.append("line")
                      .attr("stroke", "currentColor")
                      .attr(x + "2", k * tickSizeInner));
  
              text = text.merge(tickEnter.append("text")
                      .attr("fill", "currentColor")
                      .attr(x, k * spacing)
                      .attr("dy", orient === top ? "0em" : orient === bottom ? "0.71em" : "0.32em"));
  
              if (context !== selection) {
                  path = path.transition(context);
                  tick = tick.transition(context);
                  line = line.transition(context);
                  text = text.transition(context);
  
                  tickExit = tickExit.transition(context)
                          .attr("opacity", epsilon)
                          .attr("transform", function (d) {
                              return isFinite(d = position(d)) ? transform(d) : this.getAttribute("transform");
                          });
  
                  tickEnter
                          .attr("opacity", epsilon)
                          .attr("transform", function (d) {
                              var p = this.parentNode.__axis;
                              return transform(p && isFinite(p = p(d)) ? p : position(d));
                          });
              }
  
              tickExit.remove();
  
              path
                      .attr("d", orient === left || orient == right
                              ? (tickSizeOuter ? "M" + k * tickSizeOuter + "," + range0 + "H0.5V" + range1 + "H" + k * tickSizeOuter : "M0.5," + range0 + "V" + range1)
                              : (tickSizeOuter ? "M" + range0 + "," + k * tickSizeOuter + "V0.5H" + range1 + "V" + k * tickSizeOuter : "M" + range0 + ",0.5H" + range1));
  
              tick
                      .attr("opacity", 1)
                      .attr("transform", function (d) {
                          return transform(position(d));
                      });
  
              line
                      .attr(x + "2", k * tickSizeInner);
  
              text
                      .attr(x, k * spacing)
                      .text(format);
  
              selection.filter(entering)
                      .attr("fill", "none")
                      .attr("font-size", 10)
                      .attr("font-family", "sans-serif")
                      .attr("text-anchor", orient === right ? "start" : orient === left ? "end" : "middle");
  
              selection
                      .each(function () {
                          this.__axis = position;
                      });
          }
  
          axis.scale = function (_) {
              return arguments.length ? (scale = _, axis) : scale;
          };
  
          axis.ticks = function () {
              return tickArguments = slice$1.call(arguments), axis;
          };
  
          axis.tickArguments = function (_) {
              return arguments.length ? (tickArguments = _ == null ? [] : slice$1.call(_), axis) : tickArguments.slice();
          };
  
          axis.tickValues = function (_) {
              return arguments.length ? (tickValues = _ == null ? null : slice$1.call(_), axis) : tickValues && tickValues.slice();
          };
  
          axis.tickFormat = function (_) {
              return arguments.length ? (tickFormat = _, axis) : tickFormat;
          };
  
          axis.tickSize = function (_) {
              return arguments.length ? (tickSizeInner = tickSizeOuter = +_, axis) : tickSizeInner;
          };
  
          axis.tickSizeInner = function (_) {
              return arguments.length ? (tickSizeInner = +_, axis) : tickSizeInner;
          };
  
          axis.tickSizeOuter = function (_) {
              return arguments.length ? (tickSizeOuter = +_, axis) : tickSizeOuter;
          };
  
          axis.tickPadding = function (_) {
              return arguments.length ? (tickPadding = +_, axis) : tickPadding;
          };
  
          return axis;
      }
  
      function axisTop(scale) {
          return axis(top, scale);
      }
  
      function axisRight(scale) {
          return axis(right, scale);
      }
  
      function axisBottom(scale) {
          return axis(bottom, scale);
      }
  
      function axisLeft(scale) {
          return axis(left, scale);
      }
  
      var noop = {value: function () {}};
  
      function dispatch() {
          for (var i = 0, n = arguments.length, _ = {}, t; i < n; ++i) {
              if (!(t = arguments[i] + "") || (t in _) || /[\s.]/.test(t))
                  throw new Error("illegal type: " + t);
              _[t] = [];
          }
          return new Dispatch(_);
      }
  
      function Dispatch(_) {
          this._ = _;
      }
  
      function parseTypenames(typenames, types) {
          return typenames.trim().split(/^|\s+/).map(function (t) {
              var name = "", i = t.indexOf(".");
              if (i >= 0)
                  name = t.slice(i + 1), t = t.slice(0, i);
              if (t && !types.hasOwnProperty(t))
                  throw new Error("unknown type: " + t);
              return {type: t, name: name};
          });
      }
  
      Dispatch.prototype = dispatch.prototype = {
          constructor: Dispatch,
          on: function (typename, callback) {
              var _ = this._,
                      T = parseTypenames(typename + "", _),
                      t,
                      i = -1,
                      n = T.length;
  
              // If no callback was specified, return the callback of the given type and name.
              if (arguments.length < 2) {
                  while (++i < n)
                      if ((t = (typename = T[i]).type) && (t = get(_[t], typename.name)))
                          return t;
                  return;
              }
  
              // If a type was specified, set the callback for the given type and name.
              // Otherwise, if a null callback was specified, remove callbacks of the given name.
              if (callback != null && typeof callback !== "function")
                  throw new Error("invalid callback: " + callback);
              while (++i < n) {
                  if (t = (typename = T[i]).type)
                      _[t] = set(_[t], typename.name, callback);
                  else if (callback == null)
                      for (t in _)
                          _[t] = set(_[t], typename.name, null);
              }
  
              return this;
          },
          copy: function () {
              var copy = {}, _ = this._;
              for (var t in _)
                  copy[t] = _[t].slice();
              return new Dispatch(copy);
          },
          call: function (type, that) {
              if ((n = arguments.length - 2) > 0)
                  for (var args = new Array(n), i = 0, n, t; i < n; ++i)
                      args[i] = arguments[i + 2];
              if (!this._.hasOwnProperty(type))
                  throw new Error("unknown type: " + type);
              for (t = this._[type], i = 0, n = t.length; i < n; ++i)
                  t[i].value.apply(that, args);
          },
          apply: function (type, that, args) {
              if (!this._.hasOwnProperty(type))
                  throw new Error("unknown type: " + type);
              for (var t = this._[type], i = 0, n = t.length; i < n; ++i)
                  t[i].value.apply(that, args);
          }
      };
  
      function get(type, name) {
          for (var i = 0, n = type.length, c; i < n; ++i) {
              if ((c = type[i]).name === name) {
                  return c.value;
              }
          }
      }
  
      function set(type, name, callback) {
          for (var i = 0, n = type.length; i < n; ++i) {
              if (type[i].name === name) {
                  type[i] = noop, type = type.slice(0, i).concat(type.slice(i + 1));
                  break;
              }
          }
          if (callback != null)
              type.push({name: name, value: callback});
          return type;
      }
  
      var xhtml = "http://www.w3.org/1999/xhtml";
  
      var namespaces = {
          svg: "http://www.w3.org/2000/svg",
          xhtml: xhtml,
          xlink: "http://www.w3.org/1999/xlink",
          xml: "http://www.w3.org/XML/1998/namespace",
          xmlns: "http://www.w3.org/2000/xmlns/"
      };
  
      function namespace(name) {
          var prefix = name += "", i = prefix.indexOf(":");
          if (i >= 0 && (prefix = name.slice(0, i)) !== "xmlns")
              name = name.slice(i + 1);
          return namespaces.hasOwnProperty(prefix) ? {space: namespaces[prefix], local: name} : name;
      }
  
      function creatorInherit(name) {
          return function () {
              var document = this.ownerDocument,
                      uri = this.namespaceURI;
              return uri === xhtml && document.documentElement.namespaceURI === xhtml
                      ? document.createElement(name)
                      : document.createElementNS(uri, name);
          };
      }
  
      function creatorFixed(fullname) {
          return function () {
              return this.ownerDocument.createElementNS(fullname.space, fullname.local);
          };
      }
  
      function creator(name) {
          var fullname = namespace(name);
          return (fullname.local
                  ? creatorFixed
                  : creatorInherit)(fullname);
      }
  
      function none() {}
  
      function selector(selector) {
          return selector == null ? none : function () {
              return this.querySelector(selector);
          };
      }
  
      function selection_select(select) {
          if (typeof select !== "function")
              select = selector(select);
  
          for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, subgroup = subgroups[j] = new Array(n), node, subnode, i = 0; i < n; ++i) {
                  if ((node = group[i]) && (subnode = select.call(node, node.__data__, i, group))) {
                      if ("__data__" in node)
                          subnode.__data__ = node.__data__;
                      subgroup[i] = subnode;
                  }
              }
          }
  
          return new Selection(subgroups, this._parents);
      }
  
      function empty() {
          return [];
      }
  
      function selectorAll(selector) {
          return selector == null ? empty : function () {
              return this.querySelectorAll(selector);
          };
      }
  
      function selection_selectAll(select) {
          if (typeof select !== "function")
              select = selectorAll(select);
  
          for (var groups = this._groups, m = groups.length, subgroups = [], parents = [], j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
                  if (node = group[i]) {
                      subgroups.push(select.call(node, node.__data__, i, group));
                      parents.push(node);
                  }
              }
          }
  
          return new Selection(subgroups, parents);
      }
  
      function matcher(selector) {
          return function () {
              return this.matches(selector);
          };
      }
  
      function selection_filter(match) {
          if (typeof match !== "function")
              match = matcher(match);
  
          for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, subgroup = subgroups[j] = [], node, i = 0; i < n; ++i) {
                  if ((node = group[i]) && match.call(node, node.__data__, i, group)) {
                      subgroup.push(node);
                  }
              }
          }
  
          return new Selection(subgroups, this._parents);
      }
  
      function sparse(update) {
          return new Array(update.length);
      }
  
      function selection_enter() {
          return new Selection(this._enter || this._groups.map(sparse), this._parents);
      }
  
      function EnterNode(parent, datum) {
          this.ownerDocument = parent.ownerDocument;
          this.namespaceURI = parent.namespaceURI;
          this._next = null;
          this._parent = parent;
          this.__data__ = datum;
      }
  
      EnterNode.prototype = {
          constructor: EnterNode,
          appendChild: function (child) {
              return this._parent.insertBefore(child, this._next);
          },
          insertBefore: function (child, next) {
              return this._parent.insertBefore(child, next);
          },
          querySelector: function (selector) {
              return this._parent.querySelector(selector);
          },
          querySelectorAll: function (selector) {
              return this._parent.querySelectorAll(selector);
          }
      };
  
      function constant$1(x) {
          return function () {
              return x;
          };
      }
  
      var keyPrefix = "$"; // Protect against keys like “__proto__”.
  
      function bindIndex(parent, group, enter, update, exit, data) {
          var i = 0,
                  node,
                  groupLength = group.length,
                  dataLength = data.length;
  
          // Put any non-null nodes that fit into update.
          // Put any null nodes into enter.
          // Put any remaining data into enter.
          for (; i < dataLength; ++i) {
              if (node = group[i]) {
                  node.__data__ = data[i];
                  update[i] = node;
              } else {
                  enter[i] = new EnterNode(parent, data[i]);
              }
          }
  
          // Put any non-null nodes that don’t fit into exit.
          for (; i < groupLength; ++i) {
              if (node = group[i]) {
                  exit[i] = node;
              }
          }
      }
  
      function bindKey(parent, group, enter, update, exit, data, key) {
          var i,
                  node,
                  nodeByKeyValue = {},
                  groupLength = group.length,
                  dataLength = data.length,
                  keyValues = new Array(groupLength),
                  keyValue;
  
          // Compute the key for each node.
          // If multiple nodes have the same key, the duplicates are added to exit.
          for (i = 0; i < groupLength; ++i) {
              if (node = group[i]) {
                  keyValues[i] = keyValue = keyPrefix + key.call(node, node.__data__, i, group);
                  if (keyValue in nodeByKeyValue) {
                      exit[i] = node;
                  } else {
                      nodeByKeyValue[keyValue] = node;
                  }
              }
          }
  
          // Compute the key for each datum.
          // If there a node associated with this key, join and add it to update.
          // If there is not (or the key is a duplicate), add it to enter.
          for (i = 0; i < dataLength; ++i) {
              keyValue = keyPrefix + key.call(parent, data[i], i, data);
              if (node = nodeByKeyValue[keyValue]) {
                  update[i] = node;
                  node.__data__ = data[i];
                  nodeByKeyValue[keyValue] = null;
              } else {
                  enter[i] = new EnterNode(parent, data[i]);
              }
          }
  
          // Add any remaining nodes that were not bound to data to exit.
          for (i = 0; i < groupLength; ++i) {
              if ((node = group[i]) && (nodeByKeyValue[keyValues[i]] === node)) {
                  exit[i] = node;
              }
          }
      }
  
      function selection_data(value, key) {
          if (!value) {
              data = new Array(this.size()), j = -1;
              this.each(function (d) {
                  data[++j] = d;
              });
              return data;
          }
  
          var bind = key ? bindKey : bindIndex,
                  parents = this._parents,
                  groups = this._groups;
  
          if (typeof value !== "function")
              value = constant$1(value);
  
          for (var m = groups.length, update = new Array(m), enter = new Array(m), exit = new Array(m), j = 0; j < m; ++j) {
              var parent = parents[j],
                      group = groups[j],
                      groupLength = group.length,
                      data = value.call(parent, parent && parent.__data__, j, parents),
                      dataLength = data.length,
                      enterGroup = enter[j] = new Array(dataLength),
                      updateGroup = update[j] = new Array(dataLength),
                      exitGroup = exit[j] = new Array(groupLength);
  
              bind(parent, group, enterGroup, updateGroup, exitGroup, data, key);
  
              // Now connect the enter nodes to their following update node, such that
              // appendChild can insert the materialized enter node before this node,
              // rather than at the end of the parent node.
              for (var i0 = 0, i1 = 0, previous, next; i0 < dataLength; ++i0) {
                  if (previous = enterGroup[i0]) {
                      if (i0 >= i1)
                          i1 = i0 + 1;
                      while (!(next = updateGroup[i1]) && ++i1 < dataLength)
                          ;
                      previous._next = next || null;
                  }
              }
          }
  
          update = new Selection(update, parents);
          update._enter = enter;
          update._exit = exit;
          return update;
      }
  
      function selection_exit() {
          return new Selection(this._exit || this._groups.map(sparse), this._parents);
      }
  
      function selection_join(onenter, onupdate, onexit) {
          var enter = this.enter(), update = this, exit = this.exit();
          enter = typeof onenter === "function" ? onenter(enter) : enter.append(onenter + "");
          if (onupdate != null)
              update = onupdate(update);
          if (onexit == null)
              exit.remove();
          else
              onexit(exit);
          return enter && update ? enter.merge(update).order() : update;
      }
  
      function selection_merge(selection) {
  
          for (var groups0 = this._groups, groups1 = selection._groups, m0 = groups0.length, m1 = groups1.length, m = Math.min(m0, m1), merges = new Array(m0), j = 0; j < m; ++j) {
              for (var group0 = groups0[j], group1 = groups1[j], n = group0.length, merge = merges[j] = new Array(n), node, i = 0; i < n; ++i) {
                  if (node = group0[i] || group1[i]) {
                      merge[i] = node;
                  }
              }
          }
  
          for (; j < m0; ++j) {
              merges[j] = groups0[j];
          }
  
          return new Selection(merges, this._parents);
      }
  
      function selection_order() {
  
          for (var groups = this._groups, j = -1, m = groups.length; ++j < m; ) {
              for (var group = groups[j], i = group.length - 1, next = group[i], node; --i >= 0; ) {
                  if (node = group[i]) {
                      if (next && node.compareDocumentPosition(next) ^ 4)
                          next.parentNode.insertBefore(node, next);
                      next = node;
                  }
              }
          }
  
          return this;
      }
  
      function selection_sort(compare) {
          if (!compare)
              compare = ascending$1;
  
          function compareNode(a, b) {
              return a && b ? compare(a.__data__, b.__data__) : !a - !b;
          }
  
          for (var groups = this._groups, m = groups.length, sortgroups = new Array(m), j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, sortgroup = sortgroups[j] = new Array(n), node, i = 0; i < n; ++i) {
                  if (node = group[i]) {
                      sortgroup[i] = node;
                  }
              }
              sortgroup.sort(compareNode);
          }
  
          return new Selection(sortgroups, this._parents).order();
      }
  
      function ascending$1(a, b) {
          return a < b ? -1 : a > b ? 1 : a >= b ? 0 : NaN;
      }
  
      function selection_call() {
          var callback = arguments[0];
          arguments[0] = this;
          callback.apply(null, arguments);
          return this;
      }
  
      function selection_nodes() {
          var nodes = new Array(this.size()), i = -1;
          this.each(function () {
              nodes[++i] = this;
          });
          return nodes;
      }
  
      function selection_node() {
  
          for (var groups = this._groups, j = 0, m = groups.length; j < m; ++j) {
              for (var group = groups[j], i = 0, n = group.length; i < n; ++i) {
                  var node = group[i];
                  if (node)
                      return node;
              }
          }
  
          return null;
      }
  
      function selection_size() {
          var size = 0;
          this.each(function () {
              ++size;
          });
          return size;
      }
  
      function selection_empty() {
          return !this.node();
      }
  
      function selection_each(callback) {
  
          for (var groups = this._groups, j = 0, m = groups.length; j < m; ++j) {
              for (var group = groups[j], i = 0, n = group.length, node; i < n; ++i) {
                  if (node = group[i])
                      callback.call(node, node.__data__, i, group);
              }
          }
  
          return this;
      }
  
      function attrRemove(name) {
          return function () {
              this.removeAttribute(name);
          };
      }
  
      function attrRemoveNS(fullname) {
          return function () {
              this.removeAttributeNS(fullname.space, fullname.local);
          };
      }
  
      function attrConstant(name, value) {
          return function () {
              this.setAttribute(name, value);
          };
      }
  
      function attrConstantNS(fullname, value) {
          return function () {
              this.setAttributeNS(fullname.space, fullname.local, value);
          };
      }
  
      function attrFunction(name, value) {
          return function () {
              var v = value.apply(this, arguments);
              if (v == null)
                  this.removeAttribute(name);
              else
                  this.setAttribute(name, v);
          };
      }
  
      function attrFunctionNS(fullname, value) {
          return function () {
              var v = value.apply(this, arguments);
              if (v == null)
                  this.removeAttributeNS(fullname.space, fullname.local);
              else
                  this.setAttributeNS(fullname.space, fullname.local, v);
          };
      }
  
      function selection_attr(name, value) {
          var fullname = namespace(name);
  
          if (arguments.length < 2) {
              var node = this.node();
              return fullname.local
                      ? node.getAttributeNS(fullname.space, fullname.local)
                      : node.getAttribute(fullname);
          }
  
          return this.each((value == null
                  ? (fullname.local ? attrRemoveNS : attrRemove) : (typeof value === "function"
                  ? (fullname.local ? attrFunctionNS : attrFunction)
                  : (fullname.local ? attrConstantNS : attrConstant)))(fullname, value));
      }
  
      function defaultView(node) {
          return (node.ownerDocument && node.ownerDocument.defaultView) // node is a Node
                  || (node.document && node) // node is a Window
                  || node.defaultView; // node is a Document
      }
  
      function styleRemove(name) {
          return function () {
              this.style.removeProperty(name);
          };
      }
  
      function styleConstant(name, value, priority) {
          return function () {
              this.style.setProperty(name, value, priority);
          };
      }
  
      function styleFunction(name, value, priority) {
          return function () {
              var v = value.apply(this, arguments);
              if (v == null)
                  this.style.removeProperty(name);
              else
                  this.style.setProperty(name, v, priority);
          };
      }
  
      function selection_style(name, value, priority) {
          return arguments.length > 1
                  ? this.each((value == null
                          ? styleRemove : typeof value === "function"
                          ? styleFunction
                          : styleConstant)(name, value, priority == null ? "" : priority))
                  : styleValue(this.node(), name);
      }
  
      function styleValue(node, name) {
          return node.style.getPropertyValue(name)
                  || defaultView(node).getComputedStyle(node, null).getPropertyValue(name);
      }
  
      function propertyRemove(name) {
          return function () {
              delete this[name];
          };
      }
  
      function propertyConstant(name, value) {
          return function () {
              this[name] = value;
          };
      }
  
      function propertyFunction(name, value) {
          return function () {
              var v = value.apply(this, arguments);
              if (v == null)
                  delete this[name];
              else
                  this[name] = v;
          };
      }
  
      function selection_property(name, value) {
          return arguments.length > 1
                  ? this.each((value == null
                          ? propertyRemove : typeof value === "function"
                          ? propertyFunction
                          : propertyConstant)(name, value))
                  : this.node()[name];
      }
  
      function classArray(string) {
          return string.trim().split(/^|\s+/);
      }
  
      function classList(node) {
          return node.classList || new ClassList(node);
      }
  
      function ClassList(node) {
          this._node = node;
          this._names = classArray(node.getAttribute("class") || "");
      }
  
      ClassList.prototype = {
          add: function (name) {
              var i = this._names.indexOf(name);
              if (i < 0) {
                  this._names.push(name);
                  this._node.setAttribute("class", this._names.join(" "));
              }
          },
          remove: function (name) {
              var i = this._names.indexOf(name);
              if (i >= 0) {
                  this._names.splice(i, 1);
                  this._node.setAttribute("class", this._names.join(" "));
              }
          },
          contains: function (name) {
              return this._names.indexOf(name) >= 0;
          }
      };
  
      function classedAdd(node, names) {
          var list = classList(node), i = -1, n = names.length;
          while (++i < n)
              list.add(names[i]);
      }
  
      function classedRemove(node, names) {
          var list = classList(node), i = -1, n = names.length;
          while (++i < n)
              list.remove(names[i]);
      }
  
      function classedTrue(names) {
          return function () {
              classedAdd(this, names);
          };
      }
  
      function classedFalse(names) {
          return function () {
              classedRemove(this, names);
          };
      }
  
      function classedFunction(names, value) {
          return function () {
              (value.apply(this, arguments) ? classedAdd : classedRemove)(this, names);
          };
      }
  
      function selection_classed(name, value) {
          var names = classArray(name + "");
  
          if (arguments.length < 2) {
              var list = classList(this.node()), i = -1, n = names.length;
              while (++i < n)
                  if (!list.contains(names[i]))
                      return false;
              return true;
          }
  
          return this.each((typeof value === "function"
                  ? classedFunction : value
                  ? classedTrue
                  : classedFalse)(names, value));
      }
  
      function textRemove() {
          this.textContent = "";
      }
  
      function textConstant(value) {
          return function () {
              this.textContent = value;
          };
      }
  
      function textFunction(value) {
          return function () {
              var v = value.apply(this, arguments);
              this.textContent = v == null ? "" : v;
          };
      }
  
      function selection_text(value) {
          return arguments.length
                  ? this.each(value == null
                          ? textRemove : (typeof value === "function"
                                  ? textFunction
                                  : textConstant)(value))
                  : this.node().textContent;
      }
  
      function htmlRemove() {
          this.innerHTML = "";
      }
  
      function htmlConstant(value) {
          return function () {
              this.innerHTML = value;
          };
      }
  
      function htmlFunction(value) {
          return function () {
              var v = value.apply(this, arguments);
              this.innerHTML = v == null ? "" : v;
          };
      }
  
      function selection_html(value) {
          return arguments.length
                  ? this.each(value == null
                          ? htmlRemove : (typeof value === "function"
                                  ? htmlFunction
                                  : htmlConstant)(value))
                  : this.node().innerHTML;
      }
  
      function raise() {
          if (this.nextSibling)
              this.parentNode.appendChild(this);
      }
  
      function selection_raise() {
          return this.each(raise);
      }
  
      function lower() {
          if (this.previousSibling)
              this.parentNode.insertBefore(this, this.parentNode.firstChild);
      }
  
      function selection_lower() {
          return this.each(lower);
      }
  
      function selection_append(name) {
          var create = typeof name === "function" ? name : creator(name);
          return this.select(function () {
              return this.appendChild(create.apply(this, arguments));
          });
      }
  
      function constantNull() {
          return null;
      }
  
      function selection_insert(name, before) {
          var create = typeof name === "function" ? name : creator(name),
                  select = before == null ? constantNull : typeof before === "function" ? before : selector(before);
          return this.select(function () {
              return this.insertBefore(create.apply(this, arguments), select.apply(this, arguments) || null);
          });
      }
  
      function remove() {
          var parent = this.parentNode;
          if (parent)
              parent.removeChild(this);
      }
  
      function selection_remove() {
          return this.each(remove);
      }
  
      function selection_cloneShallow() {
          var clone = this.cloneNode(false), parent = this.parentNode;
          return parent ? parent.insertBefore(clone, this.nextSibling) : clone;
      }
  
      function selection_cloneDeep() {
          var clone = this.cloneNode(true), parent = this.parentNode;
          return parent ? parent.insertBefore(clone, this.nextSibling) : clone;
      }
  
      function selection_clone(deep) {
          return this.select(deep ? selection_cloneDeep : selection_cloneShallow);
      }
  
      function selection_datum(value) {
          return arguments.length
                  ? this.property("__data__", value)
                  : this.node().__data__;
      }
  
      var filterEvents = {};
  
      exports.event = null;
  
      if (typeof document !== "undefined") {
          var element = document.documentElement;
          if (!("onmouseenter" in element)) {
              filterEvents = {mouseenter: "mouseover", mouseleave: "mouseout"};
          }
      }
  
      function filterContextListener(listener, index, group) {
          listener = contextListener(listener, index, group);
          return function (event) {
              var related = event.relatedTarget;
              if (!related || (related !== this && !(related.compareDocumentPosition(this) & 8))) {
                  listener.call(this, event);
              }
          };
      }
  
      function contextListener(listener, index, group) {
          return function (event1) {
              var event0 = exports.event; // Events can be reentrant (e.g., focus).
              exports.event = event1;
              try {
                  listener.call(this, this.__data__, index, group);
              } finally {
                  exports.event = event0;
              }
          };
      }
  
      function parseTypenames$1(typenames) {
          return typenames.trim().split(/^|\s+/).map(function (t) {
              var name = "", i = t.indexOf(".");
              if (i >= 0)
                  name = t.slice(i + 1), t = t.slice(0, i);
              return {type: t, name: name};
          });
      }
  
      function onRemove(typename) {
          return function () {
              var on = this.__on;
              if (!on)
                  return;
              for (var j = 0, i = -1, m = on.length, o; j < m; ++j) {
                  if (o = on[j], (!typename.type || o.type === typename.type) && o.name === typename.name) {
                      this.removeEventListener(o.type, o.listener, o.capture);
                  } else {
                      on[++i] = o;
                  }
              }
              if (++i)
                  on.length = i;
              else
                  delete this.__on;
          };
      }
  
      function onAdd(typename, value, capture) {
          var wrap = filterEvents.hasOwnProperty(typename.type) ? filterContextListener : contextListener;
          return function (d, i, group) {
              var on = this.__on, o, listener = wrap(value, i, group);
              if (on)
                  for (var j = 0, m = on.length; j < m; ++j) {
                      if ((o = on[j]).type === typename.type && o.name === typename.name) {
                          this.removeEventListener(o.type, o.listener, o.capture);
                          this.addEventListener(o.type, o.listener = listener, o.capture = capture);
                          o.value = value;
                          return;
                      }
                  }
              this.addEventListener(typename.type, listener, capture);
              o = {type: typename.type, name: typename.name, value: value, listener: listener, capture: capture};
              if (!on)
                  this.__on = [o];
              else
                  on.push(o);
          };
      }
  
      function selection_on(typename, value, capture) {
          var typenames = parseTypenames$1(typename + ""), i, n = typenames.length, t;
  
          if (arguments.length < 2) {
              var on = this.node().__on;
              if (on)
                  for (var j = 0, m = on.length, o; j < m; ++j) {
                      for (i = 0, o = on[j]; i < n; ++i) {
                          if ((t = typenames[i]).type === o.type && t.name === o.name) {
                              return o.value;
                          }
                      }
                  }
              return;
          }
  
          on = value ? onAdd : onRemove;
          if (capture == null)
              capture = false;
          for (i = 0; i < n; ++i)
              this.each(on(typenames[i], value, capture));
          return this;
      }
  
      function customEvent(event1, listener, that, args) {
          var event0 = exports.event;
          event1.sourceEvent = exports.event;
          exports.event = event1;
          try {
              return listener.apply(that, args);
          } finally {
              exports.event = event0;
          }
      }
  
      function dispatchEvent(node, type, params) {
          var window = defaultView(node),
                  event = window.CustomEvent;
  
          if (typeof event === "function") {
              event = new event(type, params);
          } else {
              event = window.document.createEvent("Event");
              if (params)
                  event.initEvent(type, params.bubbles, params.cancelable), event.detail = params.detail;
              else
                  event.initEvent(type, false, false);
          }
  
          node.dispatchEvent(event);
      }
  
      function dispatchConstant(type, params) {
          return function () {
              return dispatchEvent(this, type, params);
          };
      }
  
      function dispatchFunction(type, params) {
          return function () {
              return dispatchEvent(this, type, params.apply(this, arguments));
          };
      }
  
      function selection_dispatch(type, params) {
          return this.each((typeof params === "function"
                  ? dispatchFunction
                  : dispatchConstant)(type, params));
      }
  
      var root = [null];
  
      function Selection(groups, parents) {
          this._groups = groups;
          this._parents = parents;
      }
  
      function selection() {
          return new Selection([[document.documentElement]], root);
      }
  
      Selection.prototype = selection.prototype = {
          constructor: Selection,
          select: selection_select,
          selectAll: selection_selectAll,
          filter: selection_filter,
          data: selection_data,
          enter: selection_enter,
          exit: selection_exit,
          join: selection_join,
          merge: selection_merge,
          order: selection_order,
          sort: selection_sort,
          call: selection_call,
          nodes: selection_nodes,
          node: selection_node,
          size: selection_size,
          empty: selection_empty,
          each: selection_each,
          attr: selection_attr,
          style: selection_style,
          property: selection_property,
          classed: selection_classed,
          text: selection_text,
          html: selection_html,
          raise: selection_raise,
          lower: selection_lower,
          append: selection_append,
          insert: selection_insert,
          remove: selection_remove,
          clone: selection_clone,
          datum: selection_datum,
          on: selection_on,
          dispatch: selection_dispatch
      };
  
      function select(selector) {
          return typeof selector === "string"
                  ? new Selection([[document.querySelector(selector)]], [document.documentElement])
                  : new Selection([[selector]], root);
      }
  
      function create(name) {
          return select(creator(name).call(document.documentElement));
      }
  
      var nextId = 0;
  
      function local() {
          return new Local;
      }
  
      function Local() {
          this._ = "@" + (++nextId).toString(36);
      }
  
      Local.prototype = local.prototype = {
          constructor: Local,
          get: function (node) {
              var id = this._;
              while (!(id in node))
                  if (!(node = node.parentNode))
                      return;
              return node[id];
          },
          set: function (node, value) {
              return node[this._] = value;
          },
          remove: function (node) {
              return this._ in node && delete node[this._];
          },
          toString: function () {
              return this._;
          }
      };
  
      function sourceEvent() {
          var current = exports.event, source;
          while (source = current.sourceEvent)
              current = source;
          return current;
      }
  
      function point(node, event) {
          var svg = node.ownerSVGElement || node;
  
          if (svg.createSVGPoint) {
              var point = svg.createSVGPoint();
              point.x = event.clientX, point.y = event.clientY;
              point = point.matrixTransform(node.getScreenCTM().inverse());
              return [point.x, point.y];
          }
  
          var rect = node.getBoundingClientRect();
          return [event.clientX - rect.left - node.clientLeft, event.clientY - rect.top - node.clientTop];
      }
  
      function mouse(node) {
          var event = sourceEvent();
          if (event.changedTouches)
              event = event.changedTouches[0];
          return point(node, event);
      }
  
      function selectAll(selector) {
          return typeof selector === "string"
                  ? new Selection([document.querySelectorAll(selector)], [document.documentElement])
                  : new Selection([selector == null ? [] : selector], root);
      }
  
      function touch(node, touches, identifier) {
          if (arguments.length < 3)
              identifier = touches, touches = sourceEvent().changedTouches;
  
          for (var i = 0, n = touches ? touches.length : 0, touch; i < n; ++i) {
              if ((touch = touches[i]).identifier === identifier) {
                  return point(node, touch);
              }
          }
  
          return null;
      }
  
      function touches(node, touches) {
          if (touches == null)
              touches = sourceEvent().touches;
  
          for (var i = 0, n = touches ? touches.length : 0, points = new Array(n); i < n; ++i) {
              points[i] = point(node, touches[i]);
          }
  
          return points;
      }
  
      function nopropagation() {
          exports.event.stopImmediatePropagation();
      }
  
      function noevent() {
          exports.event.preventDefault();
          exports.event.stopImmediatePropagation();
      }
  
      function dragDisable(view) {
          var root = view.document.documentElement,
                  selection = select(view).on("dragstart.drag", noevent, true);
          if ("onselectstart" in root) {
              selection.on("selectstart.drag", noevent, true);
          } else {
              root.__noselect = root.style.MozUserSelect;
              root.style.MozUserSelect = "none";
          }
      }
  
      function yesdrag(view, noclick) {
          var root = view.document.documentElement,
                  selection = select(view).on("dragstart.drag", null);
          if (noclick) {
              selection.on("click.drag", noevent, true);
              setTimeout(function () {
                  selection.on("click.drag", null);
              }, 0);
          }
          if ("onselectstart" in root) {
              selection.on("selectstart.drag", null);
          } else {
              root.style.MozUserSelect = root.__noselect;
              delete root.__noselect;
          }
      }
  
      function constant$2(x) {
          return function () {
              return x;
          };
      }
  
      function DragEvent(target, type, subject, id, active, x, y, dx, dy, dispatch) {
          this.target = target;
          this.type = type;
          this.subject = subject;
          this.identifier = id;
          this.active = active;
          this.x = x;
          this.y = y;
          this.dx = dx;
          this.dy = dy;
          this._ = dispatch;
      }
  
      DragEvent.prototype.on = function () {
          var value = this._.on.apply(this._, arguments);
          return value === this._ ? this : value;
      };
  
  // Ignore right-click, since that should open the context menu.
      function defaultFilter() {
          return !exports.event.ctrlKey && !exports.event.button;
      }
  
      function defaultContainer() {
          return this.parentNode;
      }
  
      function defaultSubject(d) {
          return d == null ? {x: exports.event.x, y: exports.event.y} : d;
      }
  
      function defaultTouchable() {
          return navigator.maxTouchPoints || ("ontouchstart" in this);
      }
  
      function drag() {
          var filter = defaultFilter,
                  container = defaultContainer,
                  subject = defaultSubject,
                  touchable = defaultTouchable,
                  gestures = {},
                  listeners = dispatch("start", "drag", "end"),
                  active = 0,
                  mousedownx,
                  mousedowny,
                  mousemoving,
                  touchending,
                  clickDistance2 = 0;
  
          function drag(selection) {
              selection
                      .on("mousedown.drag", mousedowned)
                      .filter(touchable)
                      .on("touchstart.drag", touchstarted)
                      .on("touchmove.drag", touchmoved)
                      .on("touchend.drag touchcancel.drag", touchended)
                      .style("touch-action", "none")
                      .style("-webkit-tap-highlight-color", "rgba(0,0,0,0)");
          }
  
          function mousedowned() {
              if (touchending || !filter.apply(this, arguments))
                  return;
              var gesture = beforestart("mouse", container.apply(this, arguments), mouse, this, arguments);
              if (!gesture)
                  return;
              select(exports.event.view).on("mousemove.drag", mousemoved, true).on("mouseup.drag", mouseupped, true);
              dragDisable(exports.event.view);
              nopropagation();
              mousemoving = false;
              mousedownx = exports.event.clientX;
              mousedowny = exports.event.clientY;
              gesture("start");
          }
  
          function mousemoved() {
              noevent();
              if (!mousemoving) {
                  var dx = exports.event.clientX - mousedownx, dy = exports.event.clientY - mousedowny;
                  mousemoving = dx * dx + dy * dy > clickDistance2;
              }
              gestures.mouse("drag");
          }
  
          function mouseupped() {
              select(exports.event.view).on("mousemove.drag mouseup.drag", null);
              yesdrag(exports.event.view, mousemoving);
              noevent();
              gestures.mouse("end");
          }
  
          function touchstarted() {
              if (!filter.apply(this, arguments))
                  return;
              var touches = exports.event.changedTouches,
                      c = container.apply(this, arguments),
                      n = touches.length, i, gesture;
  
              for (i = 0; i < n; ++i) {
                  if (gesture = beforestart(touches[i].identifier, c, touch, this, arguments)) {
                      nopropagation();
                      gesture("start");
                  }
              }
          }
  
          function touchmoved() {
              var touches = exports.event.changedTouches,
                      n = touches.length, i, gesture;
  
              for (i = 0; i < n; ++i) {
                  if (gesture = gestures[touches[i].identifier]) {
                      noevent();
                      gesture("drag");
                  }
              }
          }
  
          function touchended() {
              var touches = exports.event.changedTouches,
                      n = touches.length, i, gesture;
  
              if (touchending)
                  clearTimeout(touchending);
              touchending = setTimeout(function () {
                  touchending = null;
              }, 500); // Ghost clicks are delayed!
              for (i = 0; i < n; ++i) {
                  if (gesture = gestures[touches[i].identifier]) {
                      nopropagation();
                      gesture("end");
                  }
              }
          }
  
          function beforestart(id, container, point, that, args) {
              var p = point(container, id), s, dx, dy,
                      sublisteners = listeners.copy();
  
              if (!customEvent(new DragEvent(drag, "beforestart", s, id, active, p[0], p[1], 0, 0, sublisteners), function () {
                  if ((exports.event.subject = s = subject.apply(that, args)) == null)
                      return false;
                  dx = s.x - p[0] || 0;
                  dy = s.y - p[1] || 0;
                  return true;
              }))
                  return;
  
              return function gesture(type) {
                  var p0 = p, n;
                  switch (type) {
                      case "start":
                          gestures[id] = gesture, n = active++;
                          break;
                      case "end":
                          delete gestures[id], --active; // nobreak
                      case "drag":
                          p = point(container, id), n = active;
                          break;
                  }
                  customEvent(new DragEvent(drag, type, s, id, n, p[0] + dx, p[1] + dy, p[0] - p0[0], p[1] - p0[1], sublisteners), sublisteners.apply, sublisteners, [type, that, args]);
              };
          }
  
          drag.filter = function (_) {
              return arguments.length ? (filter = typeof _ === "function" ? _ : constant$2(!!_), drag) : filter;
          };
  
          drag.container = function (_) {
              return arguments.length ? (container = typeof _ === "function" ? _ : constant$2(_), drag) : container;
          };
  
          drag.subject = function (_) {
              return arguments.length ? (subject = typeof _ === "function" ? _ : constant$2(_), drag) : subject;
          };
  
          drag.touchable = function (_) {
              return arguments.length ? (touchable = typeof _ === "function" ? _ : constant$2(!!_), drag) : touchable;
          };
  
          drag.on = function () {
              var value = listeners.on.apply(listeners, arguments);
              return value === listeners ? drag : value;
          };
  
          drag.clickDistance = function (_) {
              return arguments.length ? (clickDistance2 = (_ = +_) * _, drag) : Math.sqrt(clickDistance2);
          };
  
          return drag;
      }
  
      function define(constructor, factory, prototype) {
          constructor.prototype = factory.prototype = prototype;
          prototype.constructor = constructor;
      }
  
      function extend(parent, definition) {
          var prototype = Object.create(parent.prototype);
          for (var key in definition)
              prototype[key] = definition[key];
          return prototype;
      }
  
      function Color() {}
  
      var darker = 0.7;
      var brighter = 1 / darker;
  
      var reI = "\\s*([+-]?\\d+)\\s*",
              reN = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)\\s*",
              reP = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)%\\s*",
              reHex = /^#([0-9a-f]{3,8})$/,
              reRgbInteger = new RegExp("^rgb\\(" + [reI, reI, reI] + "\\)$"),
              reRgbPercent = new RegExp("^rgb\\(" + [reP, reP, reP] + "\\)$"),
              reRgbaInteger = new RegExp("^rgba\\(" + [reI, reI, reI, reN] + "\\)$"),
              reRgbaPercent = new RegExp("^rgba\\(" + [reP, reP, reP, reN] + "\\)$"),
              reHslPercent = new RegExp("^hsl\\(" + [reN, reP, reP] + "\\)$"),
              reHslaPercent = new RegExp("^hsla\\(" + [reN, reP, reP, reN] + "\\)$");
  
      var named = {
          aliceblue: 0xf0f8ff,
          antiquewhite: 0xfaebd7,
          aqua: 0x00ffff,
          aquamarine: 0x7fffd4,
          azure: 0xf0ffff,
          beige: 0xf5f5dc,
          bisque: 0xffe4c4,
          black: 0x000000,
          blanchedalmond: 0xffebcd,
          blue: 0x0000ff,
          blueviolet: 0x8a2be2,
          brown: 0xa52a2a,
          burlywood: 0xdeb887,
          cadetblue: 0x5f9ea0,
          chartreuse: 0x7fff00,
          chocolate: 0xd2691e,
          coral: 0xff7f50,
          cornflowerblue: 0x6495ed,
          cornsilk: 0xfff8dc,
          crimson: 0xdc143c,
          cyan: 0x00ffff,
          darkblue: 0x00008b,
          darkcyan: 0x008b8b,
          darkgoldenrod: 0xb8860b,
          darkgray: 0xa9a9a9,
          darkgreen: 0x006400,
          darkgrey: 0xa9a9a9,
          darkkhaki: 0xbdb76b,
          darkmagenta: 0x8b008b,
          darkolivegreen: 0x556b2f,
          darkorange: 0xff8c00,
          darkorchid: 0x9932cc,
          darkred: 0x8b0000,
          darksalmon: 0xe9967a,
          darkseagreen: 0x8fbc8f,
          darkslateblue: 0x483d8b,
          darkslategray: 0x2f4f4f,
          darkslategrey: 0x2f4f4f,
          darkturquoise: 0x00ced1,
          darkviolet: 0x9400d3,
          deeppink: 0xff1493,
          deepskyblue: 0x00bfff,
          dimgray: 0x696969,
          dimgrey: 0x696969,
          dodgerblue: 0x1e90ff,
          firebrick: 0xb22222,
          floralwhite: 0xfffaf0,
          forestgreen: 0x228b22,
          fuchsia: 0xff00ff,
          gainsboro: 0xdcdcdc,
          ghostwhite: 0xf8f8ff,
          gold: 0xffd700,
          goldenrod: 0xdaa520,
          gray: 0x808080,
          green: 0x008000,
          greenyellow: 0xadff2f,
          grey: 0x808080,
          honeydew: 0xf0fff0,
          hotpink: 0xff69b4,
          indianred: 0xcd5c5c,
          indigo: 0x4b0082,
          ivory: 0xfffff0,
          khaki: 0xf0e68c,
          lavender: 0xe6e6fa,
          lavenderblush: 0xfff0f5,
          lawngreen: 0x7cfc00,
          lemonchiffon: 0xfffacd,
          lightblue: 0xadd8e6,
          lightcoral: 0xf08080,
          lightcyan: 0xe0ffff,
          lightgoldenrodyellow: 0xfafad2,
          lightgray: 0xd3d3d3,
          lightgreen: 0x90ee90,
          lightgrey: 0xd3d3d3,
          lightpink: 0xffb6c1,
          lightsalmon: 0xffa07a,
          lightseagreen: 0x20b2aa,
          lightskyblue: 0x87cefa,
          lightslategray: 0x778899,
          lightslategrey: 0x778899,
          lightsteelblue: 0xb0c4de,
          lightyellow: 0xffffe0,
          lime: 0x00ff00,
          limegreen: 0x32cd32,
          linen: 0xfaf0e6,
          magenta: 0xff00ff,
          maroon: 0x800000,
          mediumaquamarine: 0x66cdaa,
          mediumblue: 0x0000cd,
          mediumorchid: 0xba55d3,
          mediumpurple: 0x9370db,
          mediumseagreen: 0x3cb371,
          mediumslateblue: 0x7b68ee,
          mediumspringgreen: 0x00fa9a,
          mediumturquoise: 0x48d1cc,
          mediumvioletred: 0xc71585,
          midnightblue: 0x191970,
          mintcream: 0xf5fffa,
          mistyrose: 0xffe4e1,
          moccasin: 0xffe4b5,
          navajowhite: 0xffdead,
          navy: 0x000080,
          oldlace: 0xfdf5e6,
          olive: 0x808000,
          olivedrab: 0x6b8e23,
          orange: 0xffa500,
          orangered: 0xff4500,
          orchid: 0xda70d6,
          palegoldenrod: 0xeee8aa,
          palegreen: 0x98fb98,
          paleturquoise: 0xafeeee,
          palevioletred: 0xdb7093,
          papayawhip: 0xffefd5,
          peachpuff: 0xffdab9,
          peru: 0xcd853f,
          pink: 0xffc0cb,
          plum: 0xdda0dd,
          powderblue: 0xb0e0e6,
          purple: 0x800080,
          rebeccapurple: 0x663399,
          red: 0xff0000,
          rosybrown: 0xbc8f8f,
          royalblue: 0x4169e1,
          saddlebrown: 0x8b4513,
          salmon: 0xfa8072,
          sandybrown: 0xf4a460,
          seagreen: 0x2e8b57,
          seashell: 0xfff5ee,
          sienna: 0xa0522d,
          silver: 0xc0c0c0,
          skyblue: 0x87ceeb,
          slateblue: 0x6a5acd,
          slategray: 0x708090,
          slategrey: 0x708090,
          snow: 0xfffafa,
          springgreen: 0x00ff7f,
          steelblue: 0x4682b4,
          tan: 0xd2b48c,
          teal: 0x008080,
          thistle: 0xd8bfd8,
          tomato: 0xff6347,
          turquoise: 0x40e0d0,
          violet: 0xee82ee,
          wheat: 0xf5deb3,
          white: 0xffffff,
          whitesmoke: 0xf5f5f5,
          yellow: 0xffff00,
          yellowgreen: 0x9acd32
      };
  
      define(Color, color, {
          copy: function (channels) {
              return Object.assign(new this.constructor, this, channels);
          },
          displayable: function () {
              return this.rgb().displayable();
          },
          hex: color_formatHex, // Deprecated! Use color.formatHex.
          formatHex: color_formatHex,
          formatHsl: color_formatHsl,
          formatRgb: color_formatRgb,
          toString: color_formatRgb
      });
  
      function color_formatHex() {
          return this.rgb().formatHex();
      }
  
      function color_formatHsl() {
          return hslConvert(this).formatHsl();
      }
  
      function color_formatRgb() {
          return this.rgb().formatRgb();
      }
  
      function color(format) {
          var m, l;
          format = (format + "").trim().toLowerCase();
          return (m = reHex.exec(format)) ? (l = m[1].length, m = parseInt(m[1], 16), l === 6 ? rgbn(m) // #ff0000
                  : l === 3 ? new Rgb((m >> 8 & 0xf) | (m >> 4 & 0xf0), (m >> 4 & 0xf) | (m & 0xf0), ((m & 0xf) << 4) | (m & 0xf), 1) // #f00
                  : l === 8 ? rgba(m >> 24 & 0xff, m >> 16 & 0xff, m >> 8 & 0xff, (m & 0xff) / 0xff) // #ff000000
                  : l === 4 ? rgba((m >> 12 & 0xf) | (m >> 8 & 0xf0), (m >> 8 & 0xf) | (m >> 4 & 0xf0), (m >> 4 & 0xf) | (m & 0xf0), (((m & 0xf) << 4) | (m & 0xf)) / 0xff) // #f000
                  : null) // invalid hex
                  : (m = reRgbInteger.exec(format)) ? new Rgb(m[1], m[2], m[3], 1) // rgb(255, 0, 0)
                  : (m = reRgbPercent.exec(format)) ? new Rgb(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, 1) // rgb(100%, 0%, 0%)
                  : (m = reRgbaInteger.exec(format)) ? rgba(m[1], m[2], m[3], m[4]) // rgba(255, 0, 0, 1)
                  : (m = reRgbaPercent.exec(format)) ? rgba(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, m[4]) // rgb(100%, 0%, 0%, 1)
                  : (m = reHslPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, 1) // hsl(120, 50%, 50%)
                  : (m = reHslaPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, m[4]) // hsla(120, 50%, 50%, 1)
                  : named.hasOwnProperty(format) ? rgbn(named[format]) // eslint-disable-line no-prototype-builtins
                  : format === "transparent" ? new Rgb(NaN, NaN, NaN, 0)
                  : null;
      }
  
      function rgbn(n) {
          return new Rgb(n >> 16 & 0xff, n >> 8 & 0xff, n & 0xff, 1);
      }
  
      function rgba(r, g, b, a) {
          if (a <= 0)
              r = g = b = NaN;
          return new Rgb(r, g, b, a);
      }
  
      function rgbConvert(o) {
          if (!(o instanceof Color))
              o = color(o);
          if (!o)
              return new Rgb;
          o = o.rgb();
          return new Rgb(o.r, o.g, o.b, o.opacity);
      }
  
      function rgb(r, g, b, opacity) {
          return arguments.length === 1 ? rgbConvert(r) : new Rgb(r, g, b, opacity == null ? 1 : opacity);
      }
  
      function Rgb(r, g, b, opacity) {
          this.r = +r;
          this.g = +g;
          this.b = +b;
          this.opacity = +opacity;
      }
  
      define(Rgb, rgb, extend(Color, {
          brighter: function (k) {
              k = k == null ? brighter : Math.pow(brighter, k);
              return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
          },
          darker: function (k) {
              k = k == null ? darker : Math.pow(darker, k);
              return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
          },
          rgb: function () {
              return this;
          },
          displayable: function () {
              return (-0.5 <= this.r && this.r < 255.5)
                      && (-0.5 <= this.g && this.g < 255.5)
                      && (-0.5 <= this.b && this.b < 255.5)
                      && (0 <= this.opacity && this.opacity <= 1);
          },
          hex: rgb_formatHex, // Deprecated! Use color.formatHex.
          formatHex: rgb_formatHex,
          formatRgb: rgb_formatRgb,
          toString: rgb_formatRgb
      }));
  
      function rgb_formatHex() {
          return "#" + hex(this.r) + hex(this.g) + hex(this.b);
      }
  
      function rgb_formatRgb() {
          var a = this.opacity;
          a = isNaN(a) ? 1 : Math.max(0, Math.min(1, a));
          return (a === 1 ? "rgb(" : "rgba(")
                  + Math.max(0, Math.min(255, Math.round(this.r) || 0)) + ", "
                  + Math.max(0, Math.min(255, Math.round(this.g) || 0)) + ", "
                  + Math.max(0, Math.min(255, Math.round(this.b) || 0))
                  + (a === 1 ? ")" : ", " + a + ")");
      }
  
      function hex(value) {
          value = Math.max(0, Math.min(255, Math.round(value) || 0));
          return (value < 16 ? "0" : "") + value.toString(16);
      }
  
      function hsla(h, s, l, a) {
          if (a <= 0)
              h = s = l = NaN;
          else if (l <= 0 || l >= 1)
              h = s = NaN;
          else if (s <= 0)
              h = NaN;
          return new Hsl(h, s, l, a);
      }
  
      function hslConvert(o) {
          if (o instanceof Hsl)
              return new Hsl(o.h, o.s, o.l, o.opacity);
          if (!(o instanceof Color))
              o = color(o);
          if (!o)
              return new Hsl;
          if (o instanceof Hsl)
              return o;
          o = o.rgb();
          var r = o.r / 255,
                  g = o.g / 255,
                  b = o.b / 255,
                  min = Math.min(r, g, b),
                  max = Math.max(r, g, b),
                  h = NaN,
                  s = max - min,
                  l = (max + min) / 2;
          if (s) {
              if (r === max)
                  h = (g - b) / s + (g < b) * 6;
              else if (g === max)
                  h = (b - r) / s + 2;
              else
                  h = (r - g) / s + 4;
              s /= l < 0.5 ? max + min : 2 - max - min;
              h *= 60;
          } else {
              s = l > 0 && l < 1 ? 0 : h;
          }
          return new Hsl(h, s, l, o.opacity);
      }
  
      function hsl(h, s, l, opacity) {
          return arguments.length === 1 ? hslConvert(h) : new Hsl(h, s, l, opacity == null ? 1 : opacity);
      }
  
      function Hsl(h, s, l, opacity) {
          this.h = +h;
          this.s = +s;
          this.l = +l;
          this.opacity = +opacity;
      }
  
      define(Hsl, hsl, extend(Color, {
          brighter: function (k) {
              k = k == null ? brighter : Math.pow(brighter, k);
              return new Hsl(this.h, this.s, this.l * k, this.opacity);
          },
          darker: function (k) {
              k = k == null ? darker : Math.pow(darker, k);
              return new Hsl(this.h, this.s, this.l * k, this.opacity);
          },
          rgb: function () {
              var h = this.h % 360 + (this.h < 0) * 360,
                      s = isNaN(h) || isNaN(this.s) ? 0 : this.s,
                      l = this.l,
                      m2 = l + (l < 0.5 ? l : 1 - l) * s,
                      m1 = 2 * l - m2;
              return new Rgb(
                      hsl2rgb(h >= 240 ? h - 240 : h + 120, m1, m2),
                      hsl2rgb(h, m1, m2),
                      hsl2rgb(h < 120 ? h + 240 : h - 120, m1, m2),
                      this.opacity
                      );
          },
          displayable: function () {
              return (0 <= this.s && this.s <= 1 || isNaN(this.s))
                      && (0 <= this.l && this.l <= 1)
                      && (0 <= this.opacity && this.opacity <= 1);
          },
          formatHsl: function () {
              var a = this.opacity;
              a = isNaN(a) ? 1 : Math.max(0, Math.min(1, a));
              return (a === 1 ? "hsl(" : "hsla(")
                      + (this.h || 0) + ", "
                      + (this.s || 0) * 100 + "%, "
                      + (this.l || 0) * 100 + "%"
                      + (a === 1 ? ")" : ", " + a + ")");
          }
      }));
  
      /* From FvD 13.37, CSS Color Module Level 3 */
      function hsl2rgb(h, m1, m2) {
          return (h < 60 ? m1 + (m2 - m1) * h / 60
                  : h < 180 ? m2
                  : h < 240 ? m1 + (m2 - m1) * (240 - h) / 60
                  : m1) * 255;
      }
  
      var deg2rad = Math.PI / 180;
      var rad2deg = 180 / Math.PI;
  
  // https://observablehq.com/@mbostock/lab-and-rgb
      var K = 18,
              Xn = 0.96422,
              Yn = 1,
              Zn = 0.82521,
              t0 = 4 / 29,
              t1 = 6 / 29,
              t2 = 3 * t1 * t1,
              t3 = t1 * t1 * t1;
  
      function labConvert(o) {
          if (o instanceof Lab)
              return new Lab(o.l, o.a, o.b, o.opacity);
          if (o instanceof Hcl)
              return hcl2lab(o);
          if (!(o instanceof Rgb))
              o = rgbConvert(o);
          var r = rgb2lrgb(o.r),
                  g = rgb2lrgb(o.g),
                  b = rgb2lrgb(o.b),
                  y = xyz2lab((0.2225045 * r + 0.7168786 * g + 0.0606169 * b) / Yn), x, z;
          if (r === g && g === b)
              x = z = y;
          else {
              x = xyz2lab((0.4360747 * r + 0.3850649 * g + 0.1430804 * b) / Xn);
              z = xyz2lab((0.0139322 * r + 0.0971045 * g + 0.7141733 * b) / Zn);
          }
          return new Lab(116 * y - 16, 500 * (x - y), 200 * (y - z), o.opacity);
      }
  
      function gray(l, opacity) {
          return new Lab(l, 0, 0, opacity == null ? 1 : opacity);
      }
  
      function lab(l, a, b, opacity) {
          return arguments.length === 1 ? labConvert(l) : new Lab(l, a, b, opacity == null ? 1 : opacity);
      }
  
      function Lab(l, a, b, opacity) {
          this.l = +l;
          this.a = +a;
          this.b = +b;
          this.opacity = +opacity;
      }
  
      define(Lab, lab, extend(Color, {
          brighter: function (k) {
              return new Lab(this.l + K * (k == null ? 1 : k), this.a, this.b, this.opacity);
          },
          darker: function (k) {
              return new Lab(this.l - K * (k == null ? 1 : k), this.a, this.b, this.opacity);
          },
          rgb: function () {
              var y = (this.l + 16) / 116,
                      x = isNaN(this.a) ? y : y + this.a / 500,
                      z = isNaN(this.b) ? y : y - this.b / 200;
              x = Xn * lab2xyz(x);
              y = Yn * lab2xyz(y);
              z = Zn * lab2xyz(z);
              return new Rgb(
                      lrgb2rgb(3.1338561 * x - 1.6168667 * y - 0.4906146 * z),
                      lrgb2rgb(-0.9787684 * x + 1.9161415 * y + 0.0334540 * z),
                      lrgb2rgb(0.0719453 * x - 0.2289914 * y + 1.4052427 * z),
                      this.opacity
                      );
          }
      }));
  
      function xyz2lab(t) {
          return t > t3 ? Math.pow(t, 1 / 3) : t / t2 + t0;
      }
  
      function lab2xyz(t) {
          return t > t1 ? t * t * t : t2 * (t - t0);
      }
  
      function lrgb2rgb(x) {
          return 255 * (x <= 0.0031308 ? 12.92 * x : 1.055 * Math.pow(x, 1 / 2.4) - 0.055);
      }
  
      function rgb2lrgb(x) {
          return (x /= 255) <= 0.04045 ? x / 12.92 : Math.pow((x + 0.055) / 1.055, 2.4);
      }
  
      function hclConvert(o) {
          if (o instanceof Hcl)
              return new Hcl(o.h, o.c, o.l, o.opacity);
          if (!(o instanceof Lab))
              o = labConvert(o);
          if (o.a === 0 && o.b === 0)
              return new Hcl(NaN, 0 < o.l && o.l < 100 ? 0 : NaN, o.l, o.opacity);
          var h = Math.atan2(o.b, o.a) * rad2deg;
          return new Hcl(h < 0 ? h + 360 : h, Math.sqrt(o.a * o.a + o.b * o.b), o.l, o.opacity);
      }
  
      function lch(l, c, h, opacity) {
          return arguments.length === 1 ? hclConvert(l) : new Hcl(h, c, l, opacity == null ? 1 : opacity);
      }
  
      function hcl(h, c, l, opacity) {
          return arguments.length === 1 ? hclConvert(h) : new Hcl(h, c, l, opacity == null ? 1 : opacity);
      }
  
      function Hcl(h, c, l, opacity) {
          this.h = +h;
          this.c = +c;
          this.l = +l;
          this.opacity = +opacity;
      }
  
      function hcl2lab(o) {
          if (isNaN(o.h))
              return new Lab(o.l, 0, 0, o.opacity);
          var h = o.h * deg2rad;
          return new Lab(o.l, Math.cos(h) * o.c, Math.sin(h) * o.c, o.opacity);
      }
  
      define(Hcl, hcl, extend(Color, {
          brighter: function (k) {
              return new Hcl(this.h, this.c, this.l + K * (k == null ? 1 : k), this.opacity);
          },
          darker: function (k) {
              return new Hcl(this.h, this.c, this.l - K * (k == null ? 1 : k), this.opacity);
          },
          rgb: function () {
              return hcl2lab(this).rgb();
          }
      }));
  
      var A = -0.14861,
              B = +1.78277,
              C = -0.29227,
              D = -0.90649,
              E = +1.97294,
              ED = E * D,
              EB = E * B,
              BC_DA = B * C - D * A;
  
      function cubehelixConvert(o) {
          if (o instanceof Cubehelix)
              return new Cubehelix(o.h, o.s, o.l, o.opacity);
          if (!(o instanceof Rgb))
              o = rgbConvert(o);
          var r = o.r / 255,
                  g = o.g / 255,
                  b = o.b / 255,
                  l = (BC_DA * b + ED * r - EB * g) / (BC_DA + ED - EB),
                  bl = b - l,
                  k = (E * (g - l) - C * bl) / D,
                  s = Math.sqrt(k * k + bl * bl) / (E * l * (1 - l)), // NaN if l=0 or l=1
                  h = s ? Math.atan2(k, bl) * rad2deg - 120 : NaN;
          return new Cubehelix(h < 0 ? h + 360 : h, s, l, o.opacity);
      }
  
      function cubehelix(h, s, l, opacity) {
          return arguments.length === 1 ? cubehelixConvert(h) : new Cubehelix(h, s, l, opacity == null ? 1 : opacity);
      }
  
      function Cubehelix(h, s, l, opacity) {
          this.h = +h;
          this.s = +s;
          this.l = +l;
          this.opacity = +opacity;
      }
  
      define(Cubehelix, cubehelix, extend(Color, {
          brighter: function (k) {
              k = k == null ? brighter : Math.pow(brighter, k);
              return new Cubehelix(this.h, this.s, this.l * k, this.opacity);
          },
          darker: function (k) {
              k = k == null ? darker : Math.pow(darker, k);
              return new Cubehelix(this.h, this.s, this.l * k, this.opacity);
          },
          rgb: function () {
              var h = isNaN(this.h) ? 0 : (this.h + 120) * deg2rad,
                      l = +this.l,
                      a = isNaN(this.s) ? 0 : this.s * l * (1 - l),
                      cosh = Math.cos(h),
                      sinh = Math.sin(h);
              return new Rgb(
                      255 * (l + a * (A * cosh + B * sinh)),
                      255 * (l + a * (C * cosh + D * sinh)),
                      255 * (l + a * (E * cosh)),
                      this.opacity
                      );
          }
      }));
  
      function basis(t1, v0, v1, v2, v3) {
          var t2 = t1 * t1, t3 = t2 * t1;
          return ((1 - 3 * t1 + 3 * t2 - t3) * v0
                  + (4 - 6 * t2 + 3 * t3) * v1
                  + (1 + 3 * t1 + 3 * t2 - 3 * t3) * v2
                  + t3 * v3) / 6;
      }
  
      function basis$1(values) {
          var n = values.length - 1;
          return function (t) {
              var i = t <= 0 ? (t = 0) : t >= 1 ? (t = 1, n - 1) : Math.floor(t * n),
                      v1 = values[i],
                      v2 = values[i + 1],
                      v0 = i > 0 ? values[i - 1] : 2 * v1 - v2,
                      v3 = i < n - 1 ? values[i + 2] : 2 * v2 - v1;
              return basis((t - i / n) * n, v0, v1, v2, v3);
          };
      }
  
      function basisClosed(values) {
          var n = values.length;
          return function (t) {
              var i = Math.floor(((t %= 1) < 0 ? ++t : t) * n),
                      v0 = values[(i + n - 1) % n],
                      v1 = values[i % n],
                      v2 = values[(i + 1) % n],
                      v3 = values[(i + 2) % n];
              return basis((t - i / n) * n, v0, v1, v2, v3);
          };
      }
  
      function constant$3(x) {
          return function () {
              return x;
          };
      }
  
      function linear(a, d) {
          return function (t) {
              return a + t * d;
          };
      }
  
      function exponential(a, b, y) {
          return a = Math.pow(a, y), b = Math.pow(b, y) - a, y = 1 / y, function (t) {
              return Math.pow(a + t * b, y);
          };
      }
  
      function hue(a, b) {
          var d = b - a;
          return d ? linear(a, d > 180 || d < -180 ? d - 360 * Math.round(d / 360) : d) : constant$3(isNaN(a) ? b : a);
      }
  
      function gamma(y) {
          return (y = +y) === 1 ? nogamma : function (a, b) {
              return b - a ? exponential(a, b, y) : constant$3(isNaN(a) ? b : a);
          };
      }
  
      function nogamma(a, b) {
          var d = b - a;
          return d ? linear(a, d) : constant$3(isNaN(a) ? b : a);
      }
  
      var interpolateRgb = (function rgbGamma(y) {
          var color = gamma(y);
  
          function rgb$1(start, end) {
              var r = color((start = rgb(start)).r, (end = rgb(end)).r),
                      g = color(start.g, end.g),
                      b = color(start.b, end.b),
                      opacity = nogamma(start.opacity, end.opacity);
              return function (t) {
                  start.r = r(t);
                  start.g = g(t);
                  start.b = b(t);
                  start.opacity = opacity(t);
                  return start + "";
              };
          }
  
          rgb$1.gamma = rgbGamma;
  
          return rgb$1;
      })(1);
  
      function rgbSpline(spline) {
          return function (colors) {
              var n = colors.length,
                      r = new Array(n),
                      g = new Array(n),
                      b = new Array(n),
                      i, color;
              for (i = 0; i < n; ++i) {
                  color = rgb(colors[i]);
                  r[i] = color.r || 0;
                  g[i] = color.g || 0;
                  b[i] = color.b || 0;
              }
              r = spline(r);
              g = spline(g);
              b = spline(b);
              color.opacity = 1;
              return function (t) {
                  color.r = r(t);
                  color.g = g(t);
                  color.b = b(t);
                  return color + "";
              };
          };
      }
  
      var rgbBasis = rgbSpline(basis$1);
      var rgbBasisClosed = rgbSpline(basisClosed);
  
      function numberArray(a, b) {
          if (!b)
              b = [];
          var n = a ? Math.min(b.length, a.length) : 0,
                  c = b.slice(),
                  i;
          return function (t) {
              for (i = 0; i < n; ++i)
                  c[i] = a[i] * (1 - t) + b[i] * t;
              return c;
          };
      }
  
      function isNumberArray(x) {
          return ArrayBuffer.isView(x) && !(x instanceof DataView);
      }
  
      function array$1(a, b) {
          return (isNumberArray(b) ? numberArray : genericArray)(a, b);
      }
  
      function genericArray(a, b) {
          var nb = b ? b.length : 0,
                  na = a ? Math.min(nb, a.length) : 0,
                  x = new Array(na),
                  c = new Array(nb),
                  i;
  
          for (i = 0; i < na; ++i)
              x[i] = interpolateValue(a[i], b[i]);
          for (; i < nb; ++i)
              c[i] = b[i];
  
          return function (t) {
              for (i = 0; i < na; ++i)
                  c[i] = x[i](t);
              return c;
          };
      }
  
      function date(a, b) {
          var d = new Date;
          return a = +a, b = +b, function (t) {
              return d.setTime(a * (1 - t) + b * t), d;
          };
      }
  
      function interpolateNumber(a, b) {
          return a = +a, b = +b, function (t) {
              return a * (1 - t) + b * t;
          };
      }
  
      function object(a, b) {
          var i = {},
                  c = {},
                  k;
  
          if (a === null || typeof a !== "object")
              a = {};
          if (b === null || typeof b !== "object")
              b = {};
  
          for (k in b) {
              if (k in a) {
                  i[k] = interpolateValue(a[k], b[k]);
              } else {
                  c[k] = b[k];
              }
          }
  
          return function (t) {
              for (k in i)
                  c[k] = i[k](t);
              return c;
          };
      }
  
      var reA = /[-+]?(?:\d+\.?\d*|\.?\d+)(?:[eE][-+]?\d+)?/g,
              reB = new RegExp(reA.source, "g");
  
      function zero(b) {
          return function () {
              return b;
          };
      }
  
      function one(b) {
          return function (t) {
              return b(t) + "";
          };
      }
  
      function interpolateString(a, b) {
          var bi = reA.lastIndex = reB.lastIndex = 0, // scan index for next number in b
                  am, // current match in a
                  bm, // current match in b
                  bs, // string preceding current number in b, if any
                  i = -1, // index in s
                  s = [], // string constants and placeholders
                  q = []; // number interpolators
  
          // Coerce inputs to strings.
          a = a + "", b = b + "";
  
          // Interpolate pairs of numbers in a & b.
          while ((am = reA.exec(a))
                  && (bm = reB.exec(b))) {
              if ((bs = bm.index) > bi) { // a string precedes the next number in b
                  bs = b.slice(bi, bs);
                  if (s[i])
                      s[i] += bs; // coalesce with previous string
                  else
                      s[++i] = bs;
              }
              if ((am = am[0]) === (bm = bm[0])) { // numbers in a & b match
                  if (s[i])
                      s[i] += bm; // coalesce with previous string
                  else
                      s[++i] = bm;
              } else { // interpolate non-matching numbers
                  s[++i] = null;
                  q.push({i: i, x: interpolateNumber(am, bm)});
              }
              bi = reB.lastIndex;
          }
  
          // Add remains of b.
          if (bi < b.length) {
              bs = b.slice(bi);
              if (s[i])
                  s[i] += bs; // coalesce with previous string
              else
                  s[++i] = bs;
          }
  
          // Special optimization for only a single match.
          // Otherwise, interpolate each of the numbers and rejoin the string.
          return s.length < 2 ? (q[0]
                  ? one(q[0].x)
                  : zero(b))
                  : (b = q.length, function (t) {
                      for (var i = 0, o; i < b; ++i)
                          s[(o = q[i]).i] = o.x(t);
                      return s.join("");
                  });
      }
  
      function interpolateValue(a, b) {
          var t = typeof b, c;
          return b == null || t === "boolean" ? constant$3(b)
                  : (t === "number" ? interpolateNumber
                          : t === "string" ? ((c = color(b)) ? (b = c, interpolateRgb) : interpolateString)
                          : b instanceof color ? interpolateRgb
                          : b instanceof Date ? date
                          : isNumberArray(b) ? numberArray
                          : Array.isArray(b) ? genericArray
                          : typeof b.valueOf !== "function" && typeof b.toString !== "function" || isNaN(b) ? object
                          : interpolateNumber)(a, b);
      }
  
      function discrete(range) {
          var n = range.length;
          return function (t) {
              return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
          };
      }
  
      function hue$1(a, b) {
          var i = hue(+a, +b);
          return function (t) {
              var x = i(t);
              return x - 360 * Math.floor(x / 360);
          };
      }
  
      function interpolateRound(a, b) {
          return a = +a, b = +b, function (t) {
              return Math.round(a * (1 - t) + b * t);
          };
      }
  
      var degrees = 180 / Math.PI;
  
      var identity$2 = {
          translateX: 0,
          translateY: 0,
          rotate: 0,
          skewX: 0,
          scaleX: 1,
          scaleY: 1
      };
  
      function decompose(a, b, c, d, e, f) {
          var scaleX, scaleY, skewX;
          if (scaleX = Math.sqrt(a * a + b * b))
              a /= scaleX, b /= scaleX;
          if (skewX = a * c + b * d)
              c -= a * skewX, d -= b * skewX;
          if (scaleY = Math.sqrt(c * c + d * d))
              c /= scaleY, d /= scaleY, skewX /= scaleY;
          if (a * d < b * c)
              a = -a, b = -b, skewX = -skewX, scaleX = -scaleX;
          return {
              translateX: e,
              translateY: f,
              rotate: Math.atan2(b, a) * degrees,
              skewX: Math.atan(skewX) * degrees,
              scaleX: scaleX,
              scaleY: scaleY
          };
      }
  
      var cssNode,
              cssRoot,
              cssView,
              svgNode;
  
      function parseCss(value) {
          if (value === "none")
              return identity$2;
          if (!cssNode)
              cssNode = document.createElement("DIV"), cssRoot = document.documentElement, cssView = document.defaultView;
          cssNode.style.transform = value;
          value = cssView.getComputedStyle(cssRoot.appendChild(cssNode), null).getPropertyValue("transform");
          cssRoot.removeChild(cssNode);
          value = value.slice(7, -1).split(",");
          return decompose(+value[0], +value[1], +value[2], +value[3], +value[4], +value[5]);
      }
  
      function parseSvg(value) {
          if (value == null)
              return identity$2;
          if (!svgNode)
              svgNode = document.createElementNS("http://www.w3.org/2000/svg", "g");
          svgNode.setAttribute("transform", value);
          if (!(value = svgNode.transform.baseVal.consolidate()))
              return identity$2;
          value = value.matrix;
          return decompose(value.a, value.b, value.c, value.d, value.e, value.f);
      }
  
      function interpolateTransform(parse, pxComma, pxParen, degParen) {
  
          function pop(s) {
              return s.length ? s.pop() + " " : "";
          }
  
          function translate(xa, ya, xb, yb, s, q) {
              if (xa !== xb || ya !== yb) {
                  var i = s.push("translate(", null, pxComma, null, pxParen);
                  q.push({i: i - 4, x: interpolateNumber(xa, xb)}, {i: i - 2, x: interpolateNumber(ya, yb)});
              } else if (xb || yb) {
                  s.push("translate(" + xb + pxComma + yb + pxParen);
              }
          }
  
          function rotate(a, b, s, q) {
              if (a !== b) {
                  if (a - b > 180)
                      b += 360;
                  else if (b - a > 180)
                      a += 360; // shortest path
                  q.push({i: s.push(pop(s) + "rotate(", null, degParen) - 2, x: interpolateNumber(a, b)});
              } else if (b) {
                  s.push(pop(s) + "rotate(" + b + degParen);
              }
          }
  
          function skewX(a, b, s, q) {
              if (a !== b) {
                  q.push({i: s.push(pop(s) + "skewX(", null, degParen) - 2, x: interpolateNumber(a, b)});
              } else if (b) {
                  s.push(pop(s) + "skewX(" + b + degParen);
              }
          }
  
          function scale(xa, ya, xb, yb, s, q) {
              if (xa !== xb || ya !== yb) {
                  var i = s.push(pop(s) + "scale(", null, ",", null, ")");
                  q.push({i: i - 4, x: interpolateNumber(xa, xb)}, {i: i - 2, x: interpolateNumber(ya, yb)});
              } else if (xb !== 1 || yb !== 1) {
                  s.push(pop(s) + "scale(" + xb + "," + yb + ")");
              }
          }
  
          return function (a, b) {
              var s = [], // string constants and placeholders
                      q = []; // number interpolators
              a = parse(a), b = parse(b);
              translate(a.translateX, a.translateY, b.translateX, b.translateY, s, q);
              rotate(a.rotate, b.rotate, s, q);
              skewX(a.skewX, b.skewX, s, q);
              scale(a.scaleX, a.scaleY, b.scaleX, b.scaleY, s, q);
              a = b = null; // gc
              return function (t) {
                  var i = -1, n = q.length, o;
                  while (++i < n)
                      s[(o = q[i]).i] = o.x(t);
                  return s.join("");
              };
          };
      }
  
      var interpolateTransformCss = interpolateTransform(parseCss, "px, ", "px)", "deg)");
      var interpolateTransformSvg = interpolateTransform(parseSvg, ", ", ")", ")");
  
      var rho = Math.SQRT2,
              rho2 = 2,
              rho4 = 4,
              epsilon2 = 1e-12;
  
      function cosh(x) {
          return ((x = Math.exp(x)) + 1 / x) / 2;
      }
  
      function sinh(x) {
          return ((x = Math.exp(x)) - 1 / x) / 2;
      }
  
      function tanh(x) {
          return ((x = Math.exp(2 * x)) - 1) / (x + 1);
      }
  
  // p0 = [ux0, uy0, w0]
  // p1 = [ux1, uy1, w1]
      function interpolateZoom(p0, p1) {
          var ux0 = p0[0], uy0 = p0[1], w0 = p0[2],
                  ux1 = p1[0], uy1 = p1[1], w1 = p1[2],
                  dx = ux1 - ux0,
                  dy = uy1 - uy0,
                  d2 = dx * dx + dy * dy,
                  i,
                  S;
  
          // Special case for u0 ≅ u1.
          if (d2 < epsilon2) {
              S = Math.log(w1 / w0) / rho;
              i = function (t) {
                  return [
                      ux0 + t * dx,
                      uy0 + t * dy,
                      w0 * Math.exp(rho * t * S)
                  ];
              };
          }
  
          // General case.
          else {
              var d1 = Math.sqrt(d2),
                      b0 = (w1 * w1 - w0 * w0 + rho4 * d2) / (2 * w0 * rho2 * d1),
                      b1 = (w1 * w1 - w0 * w0 - rho4 * d2) / (2 * w1 * rho2 * d1),
                      r0 = Math.log(Math.sqrt(b0 * b0 + 1) - b0),
                      r1 = Math.log(Math.sqrt(b1 * b1 + 1) - b1);
              S = (r1 - r0) / rho;
              i = function (t) {
                  var s = t * S,
                          coshr0 = cosh(r0),
                          u = w0 / (rho2 * d1) * (coshr0 * tanh(rho * s + r0) - sinh(r0));
                  return [
                      ux0 + u * dx,
                      uy0 + u * dy,
                      w0 * coshr0 / cosh(rho * s + r0)
                  ];
              };
          }
  
          i.duration = S * 1000;
  
          return i;
      }
  
      function hsl$1(hue) {
          return function (start, end) {
              var h = hue((start = hsl(start)).h, (end = hsl(end)).h),
                      s = nogamma(start.s, end.s),
                      l = nogamma(start.l, end.l),
                      opacity = nogamma(start.opacity, end.opacity);
              return function (t) {
                  start.h = h(t);
                  start.s = s(t);
                  start.l = l(t);
                  start.opacity = opacity(t);
                  return start + "";
              };
          }
      }
  
      var hsl$2 = hsl$1(hue);
      var hslLong = hsl$1(nogamma);
  
      function lab$1(start, end) {
          var l = nogamma((start = lab(start)).l, (end = lab(end)).l),
                  a = nogamma(start.a, end.a),
                  b = nogamma(start.b, end.b),
                  opacity = nogamma(start.opacity, end.opacity);
          return function (t) {
              start.l = l(t);
              start.a = a(t);
              start.b = b(t);
              start.opacity = opacity(t);
              return start + "";
          };
      }
  
      function hcl$1(hue) {
          return function (start, end) {
              var h = hue((start = hcl(start)).h, (end = hcl(end)).h),
                      c = nogamma(start.c, end.c),
                      l = nogamma(start.l, end.l),
                      opacity = nogamma(start.opacity, end.opacity);
              return function (t) {
                  start.h = h(t);
                  start.c = c(t);
                  start.l = l(t);
                  start.opacity = opacity(t);
                  return start + "";
              };
          }
      }
  
      var hcl$2 = hcl$1(hue);
      var hclLong = hcl$1(nogamma);
  
      function cubehelix$1(hue) {
          return (function cubehelixGamma(y) {
              y = +y;
  
              function cubehelix$1(start, end) {
                  var h = hue((start = cubehelix(start)).h, (end = cubehelix(end)).h),
                          s = nogamma(start.s, end.s),
                          l = nogamma(start.l, end.l),
                          opacity = nogamma(start.opacity, end.opacity);
                  return function (t) {
                      start.h = h(t);
                      start.s = s(t);
                      start.l = l(Math.pow(t, y));
                      start.opacity = opacity(t);
                      return start + "";
                  };
              }
  
              cubehelix$1.gamma = cubehelixGamma;
  
              return cubehelix$1;
          })(1);
      }
  
      var cubehelix$2 = cubehelix$1(hue);
      var cubehelixLong = cubehelix$1(nogamma);
  
      function piecewise(interpolate, values) {
          var i = 0, n = values.length - 1, v = values[0], I = new Array(n < 0 ? 0 : n);
          while (i < n)
              I[i] = interpolate(v, v = values[++i]);
          return function (t) {
              var i = Math.max(0, Math.min(n - 1, Math.floor(t *= n)));
              return I[i](t - i);
          };
      }
  
      function quantize(interpolator, n) {
          var samples = new Array(n);
          for (var i = 0; i < n; ++i)
              samples[i] = interpolator(i / (n - 1));
          return samples;
      }
  
      var frame = 0, // is an animation frame pending?
              timeout = 0, // is a timeout pending?
              interval = 0, // are any timers active?
              pokeDelay = 1000, // how frequently we check for clock skew
              taskHead,
              taskTail,
              clockLast = 0,
              clockNow = 0,
              clockSkew = 0,
              clock = typeof performance === "object" && performance.now ? performance : Date,
              setFrame = typeof window === "object" && window.requestAnimationFrame ? window.requestAnimationFrame.bind(window) : function (f) {
          setTimeout(f, 17);
      };
  
      function now() {
          return clockNow || (setFrame(clearNow), clockNow = clock.now() + clockSkew);
      }
  
      function clearNow() {
          clockNow = 0;
      }
  
      function Timer() {
          this._call =
                  this._time =
                  this._next = null;
      }
  
      Timer.prototype = timer.prototype = {
          constructor: Timer,
          restart: function (callback, delay, time) {
              if (typeof callback !== "function")
                  throw new TypeError("callback is not a function");
              time = (time == null ? now() : +time) + (delay == null ? 0 : +delay);
              if (!this._next && taskTail !== this) {
                  if (taskTail)
                      taskTail._next = this;
                  else
                      taskHead = this;
                  taskTail = this;
              }
              this._call = callback;
              this._time = time;
              sleep();
          },
          stop: function () {
              if (this._call) {
                  this._call = null;
                  this._time = Infinity;
                  sleep();
              }
          }
      };
  
      function timer(callback, delay, time) {
          var t = new Timer;
          t.restart(callback, delay, time);
          return t;
      }
  
      function timerFlush() {
          now(); // Get the current time, if not already set.
          ++frame; // Pretend we’ve set an alarm, if we haven’t already.
          var t = taskHead, e;
          while (t) {
              if ((e = clockNow - t._time) >= 0)
                  t._call.call(null, e);
              t = t._next;
          }
          --frame;
      }
  
      function wake() {
          clockNow = (clockLast = clock.now()) + clockSkew;
          frame = timeout = 0;
          try {
              timerFlush();
          } finally {
              frame = 0;
              nap();
              clockNow = 0;
          }
      }
  
      function poke() {
          var now = clock.now(), delay = now - clockLast;
          if (delay > pokeDelay)
              clockSkew -= delay, clockLast = now;
      }
  
      function nap() {
          var t0, t1 = taskHead, t2, time = Infinity;
          while (t1) {
              if (t1._call) {
                  if (time > t1._time)
                      time = t1._time;
                  t0 = t1, t1 = t1._next;
              } else {
                  t2 = t1._next, t1._next = null;
                  t1 = t0 ? t0._next = t2 : taskHead = t2;
              }
          }
          taskTail = t0;
          sleep(time);
      }
  
      function sleep(time) {
          if (frame)
              return; // Soonest alarm already set, or will be.
          if (timeout)
              timeout = clearTimeout(timeout);
          var delay = time - clockNow; // Strictly less than if we recomputed clockNow.
          if (delay > 24) {
              if (time < Infinity)
                  timeout = setTimeout(wake, time - clock.now() - clockSkew);
              if (interval)
                  interval = clearInterval(interval);
          } else {
              if (!interval)
                  clockLast = clock.now(), interval = setInterval(poke, pokeDelay);
              frame = 1, setFrame(wake);
          }
      }
  
      function timeout$1(callback, delay, time) {
          var t = new Timer;
          delay = delay == null ? 0 : +delay;
          t.restart(function (elapsed) {
              t.stop();
              callback(elapsed + delay);
          }, delay, time);
          return t;
      }
  
      function interval$1(callback, delay, time) {
          var t = new Timer, total = delay;
          if (delay == null)
              return t.restart(callback, delay, time), t;
          delay = +delay, time = time == null ? now() : +time;
          t.restart(function tick(elapsed) {
              elapsed += total;
              t.restart(tick, total += delay, time);
              callback(elapsed);
          }, delay, time);
          return t;
      }
  
      var emptyOn = dispatch("start", "end", "cancel", "interrupt");
      var emptyTween = [];
  
      var CREATED = 0;
      var SCHEDULED = 1;
      var STARTING = 2;
      var STARTED = 3;
      var RUNNING = 4;
      var ENDING = 5;
      var ENDED = 6;
  
      function schedule(node, name, id, index, group, timing) {
          var schedules = node.__transition;
          if (!schedules)
              node.__transition = {};
          else if (id in schedules)
              return;
          create$1(node, id, {
              name: name,
              index: index, // For context during callback.
              group: group, // For context during callback.
              on: emptyOn,
              tween: emptyTween,
              time: timing.time,
              delay: timing.delay,
              duration: timing.duration,
              ease: timing.ease,
              timer: null,
              state: CREATED
          });
      }
  
      function init(node, id) {
          var schedule = get$1(node, id);
          if (schedule.state > CREATED)
              throw new Error("too late; already scheduled");
          return schedule;
      }
  
      function set$1(node, id) {
          var schedule = get$1(node, id);
          if (schedule.state > STARTED)
              throw new Error("too late; already running");
          return schedule;
      }
  
      function get$1(node, id) {
          var schedule = node.__transition;
          if (!schedule || !(schedule = schedule[id]))
              throw new Error("transition not found");
          return schedule;
      }
  
      function create$1(node, id, self) {
          var schedules = node.__transition,
                  tween;
  
          // Initialize the self timer when the transition is created.
          // Note the actual delay is not known until the first callback!
          schedules[id] = self;
          self.timer = timer(schedule, 0, self.time);
  
          function schedule(elapsed) {
              self.state = SCHEDULED;
              self.timer.restart(start, self.delay, self.time);
  
              // If the elapsed delay is less than our first sleep, start immediately.
              if (self.delay <= elapsed)
                  start(elapsed - self.delay);
          }
  
          function start(elapsed) {
              var i, j, n, o;
  
              // If the state is not SCHEDULED, then we previously errored on start.
              if (self.state !== SCHEDULED)
                  return stop();
  
              for (i in schedules) {
                  o = schedules[i];
                  if (o.name !== self.name)
                      continue;
  
                  // While this element already has a starting transition during this frame,
                  // defer starting an interrupting transition until that transition has a
                  // chance to tick (and possibly end); see d3/d3-transition#54!
                  if (o.state === STARTED)
                      return timeout$1(start);
  
                  // Interrupt the active transition, if any.
                  if (o.state === RUNNING) {
                      o.state = ENDED;
                      o.timer.stop();
                      o.on.call("interrupt", node, node.__data__, o.index, o.group);
                      delete schedules[i];
                  }
  
                  // Cancel any pre-empted transitions.
                  else if (+i < id) {
                      o.state = ENDED;
                      o.timer.stop();
                      o.on.call("cancel", node, node.__data__, o.index, o.group);
                      delete schedules[i];
                  }
              }
  
              // Defer the first tick to end of the current frame; see d3/d3#1576.
              // Note the transition may be canceled after start and before the first tick!
              // Note this must be scheduled before the start event; see d3/d3-transition#16!
              // Assuming this is successful, subsequent callbacks go straight to tick.
              timeout$1(function () {
                  if (self.state === STARTED) {
                      self.state = RUNNING;
                      self.timer.restart(tick, self.delay, self.time);
                      tick(elapsed);
                  }
              });
  
              // Dispatch the start event.
              // Note this must be done before the tween are initialized.
              self.state = STARTING;
              self.on.call("start", node, node.__data__, self.index, self.group);
              if (self.state !== STARTING)
                  return; // interrupted
              self.state = STARTED;
  
              // Initialize the tween, deleting null tween.
              tween = new Array(n = self.tween.length);
              for (i = 0, j = -1; i < n; ++i) {
                  if (o = self.tween[i].value.call(node, node.__data__, self.index, self.group)) {
                      tween[++j] = o;
                  }
              }
              tween.length = j + 1;
          }
  
          function tick(elapsed) {
              var t = elapsed < self.duration ? self.ease.call(null, elapsed / self.duration) : (self.timer.restart(stop), self.state = ENDING, 1),
                      i = -1,
                      n = tween.length;
  
              while (++i < n) {
                  tween[i].call(node, t);
              }
  
              // Dispatch the end event.
              if (self.state === ENDING) {
                  self.on.call("end", node, node.__data__, self.index, self.group);
                  stop();
              }
          }
  
          function stop() {
              self.state = ENDED;
              self.timer.stop();
              delete schedules[id];
              for (var i in schedules)
                  return; // eslint-disable-line no-unused-vars
              delete node.__transition;
          }
      }
  
      function interrupt(node, name) {
          var schedules = node.__transition,
                  schedule,
                  active,
                  empty = true,
                  i;
  
          if (!schedules)
              return;
  
          name = name == null ? null : name + "";
  
          for (i in schedules) {
              if ((schedule = schedules[i]).name !== name) {
                  empty = false;
                  continue;
              }
              active = schedule.state > STARTING && schedule.state < ENDING;
              schedule.state = ENDED;
              schedule.timer.stop();
              schedule.on.call(active ? "interrupt" : "cancel", node, node.__data__, schedule.index, schedule.group);
              delete schedules[i];
          }
  
          if (empty)
              delete node.__transition;
      }
  
      function selection_interrupt(name) {
          return this.each(function () {
              interrupt(this, name);
          });
      }
  
      function tweenRemove(id, name) {
          var tween0, tween1;
          return function () {
              var schedule = set$1(this, id),
                      tween = schedule.tween;
  
              // If this node shared tween with the previous node,
              // just assign the updated shared tween and we’re done!
              // Otherwise, copy-on-write.
              if (tween !== tween0) {
                  tween1 = tween0 = tween;
                  for (var i = 0, n = tween1.length; i < n; ++i) {
                      if (tween1[i].name === name) {
                          tween1 = tween1.slice();
                          tween1.splice(i, 1);
                          break;
                      }
                  }
              }
  
              schedule.tween = tween1;
          };
      }
  
      function tweenFunction(id, name, value) {
          var tween0, tween1;
          if (typeof value !== "function")
              throw new Error;
          return function () {
              var schedule = set$1(this, id),
                      tween = schedule.tween;
  
              // If this node shared tween with the previous node,
              // just assign the updated shared tween and we’re done!
              // Otherwise, copy-on-write.
              if (tween !== tween0) {
                  tween1 = (tween0 = tween).slice();
                  for (var t = {name: name, value: value}, i = 0, n = tween1.length; i < n; ++i) {
                      if (tween1[i].name === name) {
                          tween1[i] = t;
                          break;
                      }
                  }
                  if (i === n)
                      tween1.push(t);
              }
  
              schedule.tween = tween1;
          };
      }
  
      function transition_tween(name, value) {
          var id = this._id;
  
          name += "";
  
          if (arguments.length < 2) {
              var tween = get$1(this.node(), id).tween;
              for (var i = 0, n = tween.length, t; i < n; ++i) {
                  if ((t = tween[i]).name === name) {
                      return t.value;
                  }
              }
              return null;
          }
  
          return this.each((value == null ? tweenRemove : tweenFunction)(id, name, value));
      }
  
      function tweenValue(transition, name, value) {
          var id = transition._id;
  
          transition.each(function () {
              var schedule = set$1(this, id);
              (schedule.value || (schedule.value = {}))[name] = value.apply(this, arguments);
          });
  
          return function (node) {
              return get$1(node, id).value[name];
          };
      }
  
      function interpolate(a, b) {
          var c;
          return (typeof b === "number" ? interpolateNumber
                  : b instanceof color ? interpolateRgb
                  : (c = color(b)) ? (b = c, interpolateRgb)
                  : interpolateString)(a, b);
      }
  
      function attrRemove$1(name) {
          return function () {
              this.removeAttribute(name);
          };
      }
  
      function attrRemoveNS$1(fullname) {
          return function () {
              this.removeAttributeNS(fullname.space, fullname.local);
          };
      }
  
      function attrConstant$1(name, interpolate, value1) {
          var string00,
                  string1 = value1 + "",
                  interpolate0;
          return function () {
              var string0 = this.getAttribute(name);
              return string0 === string1 ? null
                      : string0 === string00 ? interpolate0
                      : interpolate0 = interpolate(string00 = string0, value1);
          };
      }
  
      function attrConstantNS$1(fullname, interpolate, value1) {
          var string00,
                  string1 = value1 + "",
                  interpolate0;
          return function () {
              var string0 = this.getAttributeNS(fullname.space, fullname.local);
              return string0 === string1 ? null
                      : string0 === string00 ? interpolate0
                      : interpolate0 = interpolate(string00 = string0, value1);
          };
      }
  
      function attrFunction$1(name, interpolate, value) {
          var string00,
                  string10,
                  interpolate0;
          return function () {
              var string0, value1 = value(this), string1;
              if (value1 == null)
                  return void this.removeAttribute(name);
              string0 = this.getAttribute(name);
              string1 = value1 + "";
              return string0 === string1 ? null
                      : string0 === string00 && string1 === string10 ? interpolate0
                      : (string10 = string1, interpolate0 = interpolate(string00 = string0, value1));
          };
      }
  
      function attrFunctionNS$1(fullname, interpolate, value) {
          var string00,
                  string10,
                  interpolate0;
          return function () {
              var string0, value1 = value(this), string1;
              if (value1 == null)
                  return void this.removeAttributeNS(fullname.space, fullname.local);
              string0 = this.getAttributeNS(fullname.space, fullname.local);
              string1 = value1 + "";
              return string0 === string1 ? null
                      : string0 === string00 && string1 === string10 ? interpolate0
                      : (string10 = string1, interpolate0 = interpolate(string00 = string0, value1));
          };
      }
  
      function transition_attr(name, value) {
          var fullname = namespace(name), i = fullname === "transform" ? interpolateTransformSvg : interpolate;
          return this.attrTween(name, typeof value === "function"
                  ? (fullname.local ? attrFunctionNS$1 : attrFunction$1)(fullname, i, tweenValue(this, "attr." + name, value))
                  : value == null ? (fullname.local ? attrRemoveNS$1 : attrRemove$1)(fullname)
                  : (fullname.local ? attrConstantNS$1 : attrConstant$1)(fullname, i, value));
      }
  
      function attrInterpolate(name, i) {
          return function (t) {
              this.setAttribute(name, i.call(this, t));
          };
      }
  
      function attrInterpolateNS(fullname, i) {
          return function (t) {
              this.setAttributeNS(fullname.space, fullname.local, i.call(this, t));
          };
      }
  
      function attrTweenNS(fullname, value) {
          var t0, i0;
          function tween() {
              var i = value.apply(this, arguments);
              if (i !== i0)
                  t0 = (i0 = i) && attrInterpolateNS(fullname, i);
              return t0;
          }
          tween._value = value;
          return tween;
      }
  
      function attrTween(name, value) {
          var t0, i0;
          function tween() {
              var i = value.apply(this, arguments);
              if (i !== i0)
                  t0 = (i0 = i) && attrInterpolate(name, i);
              return t0;
          }
          tween._value = value;
          return tween;
      }
  
      function transition_attrTween(name, value) {
          var key = "attr." + name;
          if (arguments.length < 2)
              return (key = this.tween(key)) && key._value;
          if (value == null)
              return this.tween(key, null);
          if (typeof value !== "function")
              throw new Error;
          var fullname = namespace(name);
          return this.tween(key, (fullname.local ? attrTweenNS : attrTween)(fullname, value));
      }
  
      function delayFunction(id, value) {
          return function () {
              init(this, id).delay = +value.apply(this, arguments);
          };
      }
  
      function delayConstant(id, value) {
          return value = +value, function () {
              init(this, id).delay = value;
          };
      }
  
      function transition_delay(value) {
          var id = this._id;
  
          return arguments.length
                  ? this.each((typeof value === "function"
                          ? delayFunction
                          : delayConstant)(id, value))
                  : get$1(this.node(), id).delay;
      }
  
      function durationFunction(id, value) {
          return function () {
              set$1(this, id).duration = +value.apply(this, arguments);
          };
      }
  
      function durationConstant(id, value) {
          return value = +value, function () {
              set$1(this, id).duration = value;
          };
      }
  
      function transition_duration(value) {
          var id = this._id;
  
          return arguments.length
                  ? this.each((typeof value === "function"
                          ? durationFunction
                          : durationConstant)(id, value))
                  : get$1(this.node(), id).duration;
      }
  
      function easeConstant(id, value) {
          if (typeof value !== "function")
              throw new Error;
          return function () {
              set$1(this, id).ease = value;
          };
      }
  
      function transition_ease(value) {
          var id = this._id;
  
          return arguments.length
                  ? this.each(easeConstant(id, value))
                  : get$1(this.node(), id).ease;
      }
  
      function transition_filter(match) {
          if (typeof match !== "function")
              match = matcher(match);
  
          for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, subgroup = subgroups[j] = [], node, i = 0; i < n; ++i) {
                  if ((node = group[i]) && match.call(node, node.__data__, i, group)) {
                      subgroup.push(node);
                  }
              }
          }
  
          return new Transition(subgroups, this._parents, this._name, this._id);
      }
  
      function transition_merge(transition) {
          if (transition._id !== this._id)
              throw new Error;
  
          for (var groups0 = this._groups, groups1 = transition._groups, m0 = groups0.length, m1 = groups1.length, m = Math.min(m0, m1), merges = new Array(m0), j = 0; j < m; ++j) {
              for (var group0 = groups0[j], group1 = groups1[j], n = group0.length, merge = merges[j] = new Array(n), node, i = 0; i < n; ++i) {
                  if (node = group0[i] || group1[i]) {
                      merge[i] = node;
                  }
              }
          }
  
          for (; j < m0; ++j) {
              merges[j] = groups0[j];
          }
  
          return new Transition(merges, this._parents, this._name, this._id);
      }
  
      function start(name) {
          return (name + "").trim().split(/^|\s+/).every(function (t) {
              var i = t.indexOf(".");
              if (i >= 0)
                  t = t.slice(0, i);
              return !t || t === "start";
          });
      }
  
      function onFunction(id, name, listener) {
          var on0, on1, sit = start(name) ? init : set$1;
          return function () {
              var schedule = sit(this, id),
                      on = schedule.on;
  
              // If this node shared a dispatch with the previous node,
              // just assign the updated shared dispatch and we’re done!
              // Otherwise, copy-on-write.
              if (on !== on0)
                  (on1 = (on0 = on).copy()).on(name, listener);
  
              schedule.on = on1;
          };
      }
  
      function transition_on(name, listener) {
          var id = this._id;
  
          return arguments.length < 2
                  ? get$1(this.node(), id).on.on(name)
                  : this.each(onFunction(id, name, listener));
      }
  
      function removeFunction(id) {
          return function () {
              var parent = this.parentNode;
              for (var i in this.__transition)
                  if (+i !== id)
                      return;
              if (parent)
                  parent.removeChild(this);
          };
      }
  
      function transition_remove() {
          return this.on("end.remove", removeFunction(this._id));
      }
  
      function transition_select(select) {
          var name = this._name,
                  id = this._id;
  
          if (typeof select !== "function")
              select = selector(select);
  
          for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, subgroup = subgroups[j] = new Array(n), node, subnode, i = 0; i < n; ++i) {
                  if ((node = group[i]) && (subnode = select.call(node, node.__data__, i, group))) {
                      if ("__data__" in node)
                          subnode.__data__ = node.__data__;
                      subgroup[i] = subnode;
                      schedule(subgroup[i], name, id, i, subgroup, get$1(node, id));
                  }
              }
          }
  
          return new Transition(subgroups, this._parents, name, id);
      }
  
      function transition_selectAll(select) {
          var name = this._name,
                  id = this._id;
  
          if (typeof select !== "function")
              select = selectorAll(select);
  
          for (var groups = this._groups, m = groups.length, subgroups = [], parents = [], j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
                  if (node = group[i]) {
                      for (var children = select.call(node, node.__data__, i, group), child, inherit = get$1(node, id), k = 0, l = children.length; k < l; ++k) {
                          if (child = children[k]) {
                              schedule(child, name, id, k, children, inherit);
                          }
                      }
                      subgroups.push(children);
                      parents.push(node);
                  }
              }
          }
  
          return new Transition(subgroups, parents, name, id);
      }
  
      var Selection$1 = selection.prototype.constructor;
  
      function transition_selection() {
          return new Selection$1(this._groups, this._parents);
      }
  
      function styleNull(name, interpolate) {
          var string00,
                  string10,
                  interpolate0;
          return function () {
              var string0 = styleValue(this, name),
                      string1 = (this.style.removeProperty(name), styleValue(this, name));
              return string0 === string1 ? null
                      : string0 === string00 && string1 === string10 ? interpolate0
                      : interpolate0 = interpolate(string00 = string0, string10 = string1);
          };
      }
  
      function styleRemove$1(name) {
          return function () {
              this.style.removeProperty(name);
          };
      }
  
      function styleConstant$1(name, interpolate, value1) {
          var string00,
                  string1 = value1 + "",
                  interpolate0;
          return function () {
              var string0 = styleValue(this, name);
              return string0 === string1 ? null
                      : string0 === string00 ? interpolate0
                      : interpolate0 = interpolate(string00 = string0, value1);
          };
      }
  
      function styleFunction$1(name, interpolate, value) {
          var string00,
                  string10,
                  interpolate0;
          return function () {
              var string0 = styleValue(this, name),
                      value1 = value(this),
                      string1 = value1 + "";
              if (value1 == null)
                  string1 = value1 = (this.style.removeProperty(name), styleValue(this, name));
              return string0 === string1 ? null
                      : string0 === string00 && string1 === string10 ? interpolate0
                      : (string10 = string1, interpolate0 = interpolate(string00 = string0, value1));
          };
      }
  
      function styleMaybeRemove(id, name) {
          var on0, on1, listener0, key = "style." + name, event = "end." + key, remove;
          return function () {
              var schedule = set$1(this, id),
                      on = schedule.on,
                      listener = schedule.value[key] == null ? remove || (remove = styleRemove$1(name)) : undefined;
  
              // If this node shared a dispatch with the previous node,
              // just assign the updated shared dispatch and we’re done!
              // Otherwise, copy-on-write.
              if (on !== on0 || listener0 !== listener)
                  (on1 = (on0 = on).copy()).on(event, listener0 = listener);
  
              schedule.on = on1;
          };
      }
  
      function transition_style(name, value, priority) {
          var i = (name += "") === "transform" ? interpolateTransformCss : interpolate;
          return value == null ? this
                  .styleTween(name, styleNull(name, i))
                  .on("end.style." + name, styleRemove$1(name))
                  : typeof value === "function" ? this
                  .styleTween(name, styleFunction$1(name, i, tweenValue(this, "style." + name, value)))
                  .each(styleMaybeRemove(this._id, name))
                  : this
                  .styleTween(name, styleConstant$1(name, i, value), priority)
                  .on("end.style." + name, null);
      }
  
      function styleInterpolate(name, i, priority) {
          return function (t) {
              this.style.setProperty(name, i.call(this, t), priority);
          };
      }
  
      function styleTween(name, value, priority) {
          var t, i0;
          function tween() {
              var i = value.apply(this, arguments);
              if (i !== i0)
                  t = (i0 = i) && styleInterpolate(name, i, priority);
              return t;
          }
          tween._value = value;
          return tween;
      }
  
      function transition_styleTween(name, value, priority) {
          var key = "style." + (name += "");
          if (arguments.length < 2)
              return (key = this.tween(key)) && key._value;
          if (value == null)
              return this.tween(key, null);
          if (typeof value !== "function")
              throw new Error;
          return this.tween(key, styleTween(name, value, priority == null ? "" : priority));
      }
  
      function textConstant$1(value) {
          return function () {
              this.textContent = value;
          };
      }
  
      function textFunction$1(value) {
          return function () {
              var value1 = value(this);
              this.textContent = value1 == null ? "" : value1;
          };
      }
  
      function transition_text(value) {
          return this.tween("text", typeof value === "function"
                  ? textFunction$1(tweenValue(this, "text", value))
                  : textConstant$1(value == null ? "" : value + ""));
      }
  
      function textInterpolate(i) {
          return function (t) {
              this.textContent = i.call(this, t);
          };
      }
  
      function textTween(value) {
          var t0, i0;
          function tween() {
              var i = value.apply(this, arguments);
              if (i !== i0)
                  t0 = (i0 = i) && textInterpolate(i);
              return t0;
          }
          tween._value = value;
          return tween;
      }
  
      function transition_textTween(value) {
          var key = "text";
          if (arguments.length < 1)
              return (key = this.tween(key)) && key._value;
          if (value == null)
              return this.tween(key, null);
          if (typeof value !== "function")
              throw new Error;
          return this.tween(key, textTween(value));
      }
  
      function transition_transition() {
          var name = this._name,
                  id0 = this._id,
                  id1 = newId();
  
          for (var groups = this._groups, m = groups.length, j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
                  if (node = group[i]) {
                      var inherit = get$1(node, id0);
                      schedule(node, name, id1, i, group, {
                          time: inherit.time + inherit.delay + inherit.duration,
                          delay: 0,
                          duration: inherit.duration,
                          ease: inherit.ease
                      });
                  }
              }
          }
  
          return new Transition(groups, this._parents, name, id1);
      }
  
      function transition_end() {
          var on0, on1, that = this, id = that._id, size = that.size();
          return new Promise(function (resolve, reject) {
              var cancel = {value: reject},
                      end = {value: function () {
                              if (--size === 0)
                                  resolve();
                          }};
  
              that.each(function () {
                  var schedule = set$1(this, id),
                          on = schedule.on;
  
                  // If this node shared a dispatch with the previous node,
                  // just assign the updated shared dispatch and we’re done!
                  // Otherwise, copy-on-write.
                  if (on !== on0) {
                      on1 = (on0 = on).copy();
                      on1._.cancel.push(cancel);
                      on1._.interrupt.push(cancel);
                      on1._.end.push(end);
                  }
  
                  schedule.on = on1;
              });
          });
      }
  
      var id = 0;
  
      function Transition(groups, parents, name, id) {
          this._groups = groups;
          this._parents = parents;
          this._name = name;
          this._id = id;
      }
  
      function transition(name) {
          return selection().transition(name);
      }
  
      function newId() {
          return ++id;
      }
  
      var selection_prototype = selection.prototype;
  
      Transition.prototype = transition.prototype = {
          constructor: Transition,
          select: transition_select,
          selectAll: transition_selectAll,
          filter: transition_filter,
          merge: transition_merge,
          selection: transition_selection,
          transition: transition_transition,
          call: selection_prototype.call,
          nodes: selection_prototype.nodes,
          node: selection_prototype.node,
          size: selection_prototype.size,
          empty: selection_prototype.empty,
          each: selection_prototype.each,
          on: transition_on,
          attr: transition_attr,
          attrTween: transition_attrTween,
          style: transition_style,
          styleTween: transition_styleTween,
          text: transition_text,
          textTween: transition_textTween,
          remove: transition_remove,
          tween: transition_tween,
          delay: transition_delay,
          duration: transition_duration,
          ease: transition_ease,
          end: transition_end
      };
  
      function linear$1(t) {
          return +t;
      }
  
      function quadIn(t) {
          return t * t;
      }
  
      function quadOut(t) {
          return t * (2 - t);
      }
  
      function quadInOut(t) {
          return ((t *= 2) <= 1 ? t * t : --t * (2 - t) + 1) / 2;
      }
  
      function cubicIn(t) {
          return t * t * t;
      }
  
      function cubicOut(t) {
          return --t * t * t + 1;
      }
  
      function cubicInOut(t) {
          return ((t *= 2) <= 1 ? t * t * t : (t -= 2) * t * t + 2) / 2;
      }
  
      var exponent = 3;
  
      var polyIn = (function custom(e) {
          e = +e;
  
          function polyIn(t) {
              return Math.pow(t, e);
          }
  
          polyIn.exponent = custom;
  
          return polyIn;
      })(exponent);
  
      var polyOut = (function custom(e) {
          e = +e;
  
          function polyOut(t) {
              return 1 - Math.pow(1 - t, e);
          }
  
          polyOut.exponent = custom;
  
          return polyOut;
      })(exponent);
  
      var polyInOut = (function custom(e) {
          e = +e;
  
          function polyInOut(t) {
              return ((t *= 2) <= 1 ? Math.pow(t, e) : 2 - Math.pow(2 - t, e)) / 2;
          }
  
          polyInOut.exponent = custom;
  
          return polyInOut;
      })(exponent);
  
      var pi = Math.PI,
              halfPi = pi / 2;
  
      function sinIn(t) {
          return 1 - Math.cos(t * halfPi);
      }
  
      function sinOut(t) {
          return Math.sin(t * halfPi);
      }
  
      function sinInOut(t) {
          return (1 - Math.cos(pi * t)) / 2;
      }
  
      function expIn(t) {
          return Math.pow(2, 10 * t - 10);
      }
  
      function expOut(t) {
          return 1 - Math.pow(2, -10 * t);
      }
  
      function expInOut(t) {
          return ((t *= 2) <= 1 ? Math.pow(2, 10 * t - 10) : 2 - Math.pow(2, 10 - 10 * t)) / 2;
      }
  
      function circleIn(t) {
          return 1 - Math.sqrt(1 - t * t);
      }
  
      function circleOut(t) {
          return Math.sqrt(1 - --t * t);
      }
  
      function circleInOut(t) {
          return ((t *= 2) <= 1 ? 1 - Math.sqrt(1 - t * t) : Math.sqrt(1 - (t -= 2) * t) + 1) / 2;
      }
  
      var b1 = 4 / 11,
              b2 = 6 / 11,
              b3 = 8 / 11,
              b4 = 3 / 4,
              b5 = 9 / 11,
              b6 = 10 / 11,
              b7 = 15 / 16,
              b8 = 21 / 22,
              b9 = 63 / 64,
              b0 = 1 / b1 / b1;
  
      function bounceIn(t) {
          return 1 - bounceOut(1 - t);
      }
  
      function bounceOut(t) {
          return (t = +t) < b1 ? b0 * t * t : t < b3 ? b0 * (t -= b2) * t + b4 : t < b6 ? b0 * (t -= b5) * t + b7 : b0 * (t -= b8) * t + b9;
      }
  
      function bounceInOut(t) {
          return ((t *= 2) <= 1 ? 1 - bounceOut(1 - t) : bounceOut(t - 1) + 1) / 2;
      }
  
      var overshoot = 1.70158;
  
      var backIn = (function custom(s) {
          s = +s;
  
          function backIn(t) {
              return t * t * ((s + 1) * t - s);
          }
  
          backIn.overshoot = custom;
  
          return backIn;
      })(overshoot);
  
      var backOut = (function custom(s) {
          s = +s;
  
          function backOut(t) {
              return --t * t * ((s + 1) * t + s) + 1;
          }
  
          backOut.overshoot = custom;
  
          return backOut;
      })(overshoot);
  
      var backInOut = (function custom(s) {
          s = +s;
  
          function backInOut(t) {
              return ((t *= 2) < 1 ? t * t * ((s + 1) * t - s) : (t -= 2) * t * ((s + 1) * t + s) + 2) / 2;
          }
  
          backInOut.overshoot = custom;
  
          return backInOut;
      })(overshoot);
  
      var tau = 2 * Math.PI,
              amplitude = 1,
              period = 0.3;
  
      var elasticIn = (function custom(a, p) {
          var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);
  
          function elasticIn(t) {
              return a * Math.pow(2, 10 * --t) * Math.sin((s - t) / p);
          }
  
          elasticIn.amplitude = function (a) {
              return custom(a, p * tau);
          };
          elasticIn.period = function (p) {
              return custom(a, p);
          };
  
          return elasticIn;
      })(amplitude, period);
  
      var elasticOut = (function custom(a, p) {
          var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);
  
          function elasticOut(t) {
              return 1 - a * Math.pow(2, -10 * (t = +t)) * Math.sin((t + s) / p);
          }
  
          elasticOut.amplitude = function (a) {
              return custom(a, p * tau);
          };
          elasticOut.period = function (p) {
              return custom(a, p);
          };
  
          return elasticOut;
      })(amplitude, period);
  
      var elasticInOut = (function custom(a, p) {
          var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);
  
          function elasticInOut(t) {
              return ((t = t * 2 - 1) < 0
                      ? a * Math.pow(2, 10 * t) * Math.sin((s - t) / p)
                      : 2 - a * Math.pow(2, -10 * t) * Math.sin((s + t) / p)) / 2;
          }
  
          elasticInOut.amplitude = function (a) {
              return custom(a, p * tau);
          };
          elasticInOut.period = function (p) {
              return custom(a, p);
          };
  
          return elasticInOut;
      })(amplitude, period);
  
      var defaultTiming = {
          time: null, // Set on use.
          delay: 0,
          duration: 250,
          ease: cubicInOut
      };
  
      function inherit(node, id) {
          var timing;
          while (!(timing = node.__transition) || !(timing = timing[id])) {
              if (!(node = node.parentNode)) {
                  return defaultTiming.time = now(), defaultTiming;
              }
          }
          return timing;
      }
  
      function selection_transition(name) {
          var id,
                  timing;
  
          if (name instanceof Transition) {
              id = name._id, name = name._name;
          } else {
              id = newId(), (timing = defaultTiming).time = now(), name = name == null ? null : name + "";
          }
  
          for (var groups = this._groups, m = groups.length, j = 0; j < m; ++j) {
              for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
                  if (node = group[i]) {
                      schedule(node, name, id, i, group, timing || inherit(node, id));
                  }
              }
          }
  
          return new Transition(groups, this._parents, name, id);
      }
  
      selection.prototype.interrupt = selection_interrupt;
      selection.prototype.transition = selection_transition;
  
      var root$1 = [null];
  
      function active(node, name) {
          var schedules = node.__transition,
                  schedule,
                  i;
  
          if (schedules) {
              name = name == null ? null : name + "";
              for (i in schedules) {
                  if ((schedule = schedules[i]).state > SCHEDULED && schedule.name === name) {
                      return new Transition([[node]], root$1, name, +i);
                  }
              }
          }
  
          return null;
      }
  
      function constant$4(x) {
          return function () {
              return x;
          };
      }
  
      function BrushEvent(target, type, selection) {
          this.target = target;
          this.type = type;
          this.selection = selection;
      }
  
      function nopropagation$1() {
          exports.event.stopImmediatePropagation();
      }
  
      function noevent$1() {
          exports.event.preventDefault();
          exports.event.stopImmediatePropagation();
      }
  
      var MODE_DRAG = {name: "drag"},
              MODE_SPACE = {name: "space"},
              MODE_HANDLE = {name: "handle"},
              MODE_CENTER = {name: "center"};
  
      function number1(e) {
          return [+e[0], +e[1]];
      }
  
      function number2(e) {
          return [number1(e[0]), number1(e[1])];
      }
  
      function toucher(identifier) {
          return function (target) {
              return touch(target, exports.event.touches, identifier);
          };
      }
  
      var X = {
          name: "x",
          handles: ["w", "e"].map(type),
          input: function (x, e) {
              return x == null ? null : [[+x[0], e[0][1]], [+x[1], e[1][1]]];
          },
          output: function (xy) {
              return xy && [xy[0][0], xy[1][0]];
          }
      };
  
      var Y = {
          name: "y",
          handles: ["n", "s"].map(type),
          input: function (y, e) {
              return y == null ? null : [[e[0][0], +y[0]], [e[1][0], +y[1]]];
          },
          output: function (xy) {
              return xy && [xy[0][1], xy[1][1]];
          }
      };
  
      var XY = {
          name: "xy",
          handles: ["n", "w", "e", "s", "nw", "ne", "sw", "se"].map(type),
          input: function (xy) {
              return xy == null ? null : number2(xy);
          },
          output: function (xy) {
              return xy;
          }
      };
  
      var cursors = {
          overlay: "crosshair",
          selection: "move",
          n: "ns-resize",
          e: "ew-resize",
          s: "ns-resize",
          w: "ew-resize",
          nw: "nwse-resize",
          ne: "nesw-resize",
          se: "nwse-resize",
          sw: "nesw-resize"
      };
  
      var flipX = {
          e: "w",
          w: "e",
          nw: "ne",
          ne: "nw",
          se: "sw",
          sw: "se"
      };
  
      var flipY = {
          n: "s",
          s: "n",
          nw: "sw",
          ne: "se",
          se: "ne",
          sw: "nw"
      };
  
      var signsX = {
          overlay: +1,
          selection: +1,
          n: null,
          e: +1,
          s: null,
          w: -1,
          nw: -1,
          ne: +1,
          se: +1,
          sw: -1
      };
  
      var signsY = {
          overlay: +1,
          selection: +1,
          n: -1,
          e: null,
          s: +1,
          w: null,
          nw: -1,
          ne: -1,
          se: +1,
          sw: +1
      };
  
      function type(t) {
          return {type: t};
      }
  
  // Ignore right-click, since that should open the context menu.
      function defaultFilter$1() {
          return !exports.event.ctrlKey && !exports.event.button;
      }
  
      function defaultExtent() {
          var svg = this.ownerSVGElement || this;
          if (svg.hasAttribute("viewBox")) {
              svg = svg.viewBox.baseVal;
              return [[svg.x, svg.y], [svg.x + svg.width, svg.y + svg.height]];
          }
          return [[0, 0], [svg.width.baseVal.value, svg.height.baseVal.value]];
      }
  
      function defaultTouchable$1() {
          return navigator.maxTouchPoints || ("ontouchstart" in this);
      }
  
  // Like d3.local, but with the name “__brush” rather than auto-generated.
      function local$1(node) {
          while (!node.__brush)
              if (!(node = node.parentNode))
                  return;
          return node.__brush;
      }
  
      function empty$1(extent) {
          return extent[0][0] === extent[1][0]
                  || extent[0][1] === extent[1][1];
      }
  
      function brushSelection(node) {
          var state = node.__brush;
          return state ? state.dim.output(state.selection) : null;
      }
  
      function brushX() {
          return brush$1(X);
      }
  
      function brushY() {
          return brush$1(Y);
      }
  
      function brush() {
          return brush$1(XY);
      }
  
      function brush$1(dim) {
          var extent = defaultExtent,
                  filter = defaultFilter$1,
                  touchable = defaultTouchable$1,
                  keys = true,
                  listeners = dispatch("start", "brush", "end"),
                  handleSize = 6,
                  touchending;
  
          function brush(group) {
              var overlay = group
                      .property("__brush", initialize)
                      .selectAll(".overlay")
                      .data([type("overlay")]);
  
              overlay.enter().append("rect")
                      .attr("class", "overlay")
                      .attr("pointer-events", "all")
                      .attr("cursor", cursors.overlay)
                      .merge(overlay)
                      .each(function () {
                          var extent = local$1(this).extent;
                          select(this)
                                  .attr("x", extent[0][0])
                                  .attr("y", extent[0][1])
                                  .attr("width", extent[1][0] - extent[0][0])
                                  .attr("height", extent[1][1] - extent[0][1]);
                      });
  
              group.selectAll(".selection")
                      .data([type("selection")])
                      .enter().append("rect")
                      .attr("class", "selection")
                      .attr("cursor", cursors.selection)
                      .attr("fill", "#777")
                      .attr("fill-opacity", 0.3)
                      .attr("stroke", "#fff")
                      .attr("shape-rendering", "crispEdges");
  
              var handle = group.selectAll(".handle")
                      .data(dim.handles, function (d) {
                          return d.type;
                      });
  
              handle.exit().remove();
  
              handle.enter().append("rect")
                      .attr("class", function (d) {
                          return "handle handle--" + d.type;
                      })
                      .attr("cursor", function (d) {
                          return cursors[d.type];
                      });
  
              group
                      .each(redraw)
                      .attr("fill", "none")
                      .attr("pointer-events", "all")
                      .on("mousedown.brush", started)
                      .filter(touchable)
                      .on("touchstart.brush", started)
                      .on("touchmove.brush", touchmoved)
                      .on("touchend.brush touchcancel.brush", touchended)
                      .style("touch-action", "none")
                      .style("-webkit-tap-highlight-color", "rgba(0,0,0,0)");
          }
  
          brush.move = function (group, selection) {
              if (group.selection) {
                  group
                          .on("start.brush", function () {
                              emitter(this, arguments).beforestart().start();
                          })
                          .on("interrupt.brush end.brush", function () {
                              emitter(this, arguments).end();
                          })
                          .tween("brush", function () {
                              var that = this,
                                      state = that.__brush,
                                      emit = emitter(that, arguments),
                                      selection0 = state.selection,
                                      selection1 = dim.input(typeof selection === "function" ? selection.apply(this, arguments) : selection, state.extent),
                                      i = interpolateValue(selection0, selection1);
  
                              function tween(t) {
                                  state.selection = t === 1 && selection1 === null ? null : i(t);
                                  redraw.call(that);
                                  emit.brush();
                              }
  
                              return selection0 !== null && selection1 !== null ? tween : tween(1);
                          });
              } else {
                  group
                          .each(function () {
                              var that = this,
                                      args = arguments,
                                      state = that.__brush,
                                      selection1 = dim.input(typeof selection === "function" ? selection.apply(that, args) : selection, state.extent),
                                      emit = emitter(that, args).beforestart();
  
                              interrupt(that);
                              state.selection = selection1 === null ? null : selection1;
                              redraw.call(that);
                              emit.start().brush().end();
                          });
              }
          };
  
          brush.clear = function (group) {
              brush.move(group, null);
          };
  
          function redraw() {
              var group = select(this),
                      selection = local$1(this).selection;
  
              if (selection) {
                  group.selectAll(".selection")
                          .style("display", null)
                          .attr("x", selection[0][0])
                          .attr("y", selection[0][1])
                          .attr("width", selection[1][0] - selection[0][0])
                          .attr("height", selection[1][1] - selection[0][1]);
  
                  group.selectAll(".handle")
                          .style("display", null)
                          .attr("x", function (d) {
                              return d.type[d.type.length - 1] === "e" ? selection[1][0] - handleSize / 2 : selection[0][0] - handleSize / 2;
                          })
                          .attr("y", function (d) {
                              return d.type[0] === "s" ? selection[1][1] - handleSize / 2 : selection[0][1] - handleSize / 2;
                          })
                          .attr("width", function (d) {
                              return d.type === "n" || d.type === "s" ? selection[1][0] - selection[0][0] + handleSize : handleSize;
                          })
                          .attr("height", function (d) {
                              return d.type === "e" || d.type === "w" ? selection[1][1] - selection[0][1] + handleSize : handleSize;
                          });
              } else {
                  group.selectAll(".selection,.handle")
                          .style("display", "none")
                          .attr("x", null)
                          .attr("y", null)
                          .attr("width", null)
                          .attr("height", null);
              }
          }
  
          function emitter(that, args, clean) {
              return (!clean && that.__brush.emitter) || new Emitter(that, args);
          }
  
          function Emitter(that, args) {
              this.that = that;
              this.args = args;
              this.state = that.__brush;
              this.active = 0;
          }
  
          Emitter.prototype = {
              beforestart: function () {
                  if (++this.active === 1)
                      this.state.emitter = this, this.starting = true;
                  return this;
              },
              start: function () {
                  if (this.starting)
                      this.starting = false, this.emit("start");
                  else
                      this.emit("brush");
                  return this;
              },
              brush: function () {
                  this.emit("brush");
                  return this;
              },
              end: function () {
                  if (--this.active === 0)
                      delete this.state.emitter, this.emit("end");
                  return this;
              },
              emit: function (type) {
                  customEvent(new BrushEvent(brush, type, dim.output(this.state.selection)), listeners.apply, listeners, [type, this.that, this.args]);
              }
          };
  
          function started() {
              if (touchending && !exports.event.touches)
                  return;
              if (!filter.apply(this, arguments))
                  return;
  
              var that = this,
                      type = exports.event.target.__data__.type,
                      mode = (keys && exports.event.metaKey ? type = "overlay" : type) === "selection" ? MODE_DRAG : (keys && exports.event.altKey ? MODE_CENTER : MODE_HANDLE),
                      signX = dim === Y ? null : signsX[type],
                      signY = dim === X ? null : signsY[type],
                      state = local$1(that),
                      extent = state.extent,
                      selection = state.selection,
                      W = extent[0][0], w0, w1,
                      N = extent[0][1], n0, n1,
                      E = extent[1][0], e0, e1,
                      S = extent[1][1], s0, s1,
                      dx = 0,
                      dy = 0,
                      moving,
                      shifting = signX && signY && keys && exports.event.shiftKey,
                      lockX,
                      lockY,
                      pointer = exports.event.touches ? toucher(exports.event.changedTouches[0].identifier) : mouse,
                      point0 = pointer(that),
                      point = point0,
                      emit = emitter(that, arguments, true).beforestart();
  
              if (type === "overlay") {
                  if (selection)
                      moving = true;
                  state.selection = selection = [
                      [w0 = dim === Y ? W : point0[0], n0 = dim === X ? N : point0[1]],
                      [e0 = dim === Y ? E : w0, s0 = dim === X ? S : n0]
                  ];
              } else {
                  w0 = selection[0][0];
                  n0 = selection[0][1];
                  e0 = selection[1][0];
                  s0 = selection[1][1];
              }
  
              w1 = w0;
              n1 = n0;
              e1 = e0;
              s1 = s0;
  
              var group = select(that)
                      .attr("pointer-events", "none");
  
              var overlay = group.selectAll(".overlay")
                      .attr("cursor", cursors[type]);
  
              if (exports.event.touches) {
                  emit.moved = moved;
                  emit.ended = ended;
              } else {
                  var view = select(exports.event.view)
                          .on("mousemove.brush", moved, true)
                          .on("mouseup.brush", ended, true);
                  if (keys)
                      view
                              .on("keydown.brush", keydowned, true)
                              .on("keyup.brush", keyupped, true);
  
                  dragDisable(exports.event.view);
              }
  
              nopropagation$1();
              interrupt(that);
              redraw.call(that);
              emit.start();
  
              function moved() {
                  var point1 = pointer(that);
                  if (shifting && !lockX && !lockY) {
                      if (Math.abs(point1[0] - point[0]) > Math.abs(point1[1] - point[1]))
                          lockY = true;
                      else
                          lockX = true;
                  }
                  point = point1;
                  moving = true;
                  noevent$1();
                  move();
              }
  
              function move() {
                  var t;
  
                  dx = point[0] - point0[0];
                  dy = point[1] - point0[1];
  
                  switch (mode) {
                      case MODE_SPACE:
                      case MODE_DRAG:
                      {
                          if (signX)
                              dx = Math.max(W - w0, Math.min(E - e0, dx)), w1 = w0 + dx, e1 = e0 + dx;
                          if (signY)
                              dy = Math.max(N - n0, Math.min(S - s0, dy)), n1 = n0 + dy, s1 = s0 + dy;
                          break;
                      }
                      case MODE_HANDLE:
                      {
                          if (signX < 0)
                              dx = Math.max(W - w0, Math.min(E - w0, dx)), w1 = w0 + dx, e1 = e0;
                          else if (signX > 0)
                              dx = Math.max(W - e0, Math.min(E - e0, dx)), w1 = w0, e1 = e0 + dx;
                          if (signY < 0)
                              dy = Math.max(N - n0, Math.min(S - n0, dy)), n1 = n0 + dy, s1 = s0;
                          else if (signY > 0)
                              dy = Math.max(N - s0, Math.min(S - s0, dy)), n1 = n0, s1 = s0 + dy;
                          break;
                      }
                      case MODE_CENTER:
                      {
                          if (signX)
                              w1 = Math.max(W, Math.min(E, w0 - dx * signX)), e1 = Math.max(W, Math.min(E, e0 + dx * signX));
                          if (signY)
                              n1 = Math.max(N, Math.min(S, n0 - dy * signY)), s1 = Math.max(N, Math.min(S, s0 + dy * signY));
                          break;
                      }
                  }
  
                  if (e1 < w1) {
                      signX *= -1;
                      t = w0, w0 = e0, e0 = t;
                      t = w1, w1 = e1, e1 = t;
                      if (type in flipX)
                          overlay.attr("cursor", cursors[type = flipX[type]]);
                  }
  
                  if (s1 < n1) {
                      signY *= -1;
                      t = n0, n0 = s0, s0 = t;
                      t = n1, n1 = s1, s1 = t;
                      if (type in flipY)
                          overlay.attr("cursor", cursors[type = flipY[type]]);
                  }
  
                  if (state.selection)
                      selection = state.selection; // May be set by brush.move!
                  if (lockX)
                      w1 = selection[0][0], e1 = selection[1][0];
                  if (lockY)
                      n1 = selection[0][1], s1 = selection[1][1];
  
                  if (selection[0][0] !== w1
                          || selection[0][1] !== n1
                          || selection[1][0] !== e1
                          || selection[1][1] !== s1) {
                      state.selection = [[w1, n1], [e1, s1]];
                      redraw.call(that);
                      emit.brush();
                  }
              }
  
              function ended() {
                  nopropagation$1();
                  if (exports.event.touches) {
                      if (exports.event.touches.length)
                          return;
                      if (touchending)
                          clearTimeout(touchending);
                      touchending = setTimeout(function () {
                          touchending = null;
                      }, 500); // Ghost clicks are delayed!
                  } else {
                      yesdrag(exports.event.view, moving);
                      view.on("keydown.brush keyup.brush mousemove.brush mouseup.brush", null);
                  }
                  group.attr("pointer-events", "all");
                  overlay.attr("cursor", cursors.overlay);
                  if (state.selection)
                      selection = state.selection; // May be set by brush.move (on start)!
                  if (empty$1(selection))
                      state.selection = null, redraw.call(that);
                  emit.end();
              }
  
              function keydowned() {
                  switch (exports.event.keyCode) {
                      case 16:
                      { // SHIFT
                          shifting = signX && signY;
                          break;
                      }
                      case 18:
                      { // ALT
                          if (mode === MODE_HANDLE) {
                              if (signX)
                                  e0 = e1 - dx * signX, w0 = w1 + dx * signX;
                              if (signY)
                                  s0 = s1 - dy * signY, n0 = n1 + dy * signY;
                              mode = MODE_CENTER;
                              move();
                          }
                          break;
                      }
                      case 32:
                      { // SPACE; takes priority over ALT
                          if (mode === MODE_HANDLE || mode === MODE_CENTER) {
                              if (signX < 0)
                                  e0 = e1 - dx;
                              else if (signX > 0)
                                  w0 = w1 - dx;
                              if (signY < 0)
                                  s0 = s1 - dy;
                              else if (signY > 0)
                                  n0 = n1 - dy;
                              mode = MODE_SPACE;
                              overlay.attr("cursor", cursors.selection);
                              move();
                          }
                          break;
                      }
                      default:
                          return;
                  }
                  noevent$1();
              }
  
              function keyupped() {
                  switch (exports.event.keyCode) {
                      case 16:
                      { // SHIFT
                          if (shifting) {
                              lockX = lockY = shifting = false;
                              move();
                          }
                          break;
                      }
                      case 18:
                      { // ALT
                          if (mode === MODE_CENTER) {
                              if (signX < 0)
                                  e0 = e1;
                              else if (signX > 0)
                                  w0 = w1;
                              if (signY < 0)
                                  s0 = s1;
                              else if (signY > 0)
                                  n0 = n1;
                              mode = MODE_HANDLE;
                              move();
                          }
                          break;
                      }
                      case 32:
                      { // SPACE
                          if (mode === MODE_SPACE) {
                              if (exports.event.altKey) {
                                  if (signX)
                                      e0 = e1 - dx * signX, w0 = w1 + dx * signX;
                                  if (signY)
                                      s0 = s1 - dy * signY, n0 = n1 + dy * signY;
                                  mode = MODE_CENTER;
                              } else {
                                  if (signX < 0)
                                      e0 = e1;
                                  else if (signX > 0)
                                      w0 = w1;
                                  if (signY < 0)
                                      s0 = s1;
                                  else if (signY > 0)
                                      n0 = n1;
                                  mode = MODE_HANDLE;
                              }
                              overlay.attr("cursor", cursors[type]);
                              move();
                          }
                          break;
                      }
                      default:
                          return;
                  }
                  noevent$1();
              }
          }
  
          function touchmoved() {
              emitter(this, arguments).moved();
          }
  
          function touchended() {
              emitter(this, arguments).ended();
          }
  
          function initialize() {
              var state = this.__brush || {selection: null};
              state.extent = number2(extent.apply(this, arguments));
              state.dim = dim;
              return state;
          }
  
          brush.extent = function (_) {
              return arguments.length ? (extent = typeof _ === "function" ? _ : constant$4(number2(_)), brush) : extent;
          };
  
          brush.filter = function (_) {
              return arguments.length ? (filter = typeof _ === "function" ? _ : constant$4(!!_), brush) : filter;
          };
  
          brush.touchable = function (_) {
              return arguments.length ? (touchable = typeof _ === "function" ? _ : constant$4(!!_), brush) : touchable;
          };
  
          brush.handleSize = function (_) {
              return arguments.length ? (handleSize = +_, brush) : handleSize;
          };
  
          brush.keyModifiers = function (_) {
              return arguments.length ? (keys = !!_, brush) : keys;
          };
  
          brush.on = function () {
              var value = listeners.on.apply(listeners, arguments);
              return value === listeners ? brush : value;
          };
  
          return brush;
      }
  
      var cos = Math.cos;
      var sin = Math.sin;
      var pi$1 = Math.PI;
      var halfPi$1 = pi$1 / 2;
      var tau$1 = pi$1 * 2;
      var max$1 = Math.max;
  
      function compareValue(compare) {
          return function (a, b) {
              return compare(
                      a.source.value + a.target.value,
                      b.source.value + b.target.value
                      );
          };
      }
  
      function chord() {
          var padAngle = 0,
                  sortGroups = null,
                  sortSubgroups = null,
                  sortChords = null;
  
          function chord(matrix) {
              var n = matrix.length,
                      groupSums = [],
                      groupIndex = sequence(n),
                      subgroupIndex = [],
                      chords = [],
                      groups = chords.groups = new Array(n),
                      subgroups = new Array(n * n),
                      k,
                      x,
                      x0,
                      dx,
                      i,
                      j;
  
              // Compute the sum.
              k = 0, i = -1;
              while (++i < n) {
                  x = 0, j = -1;
                  while (++j < n) {
                      x += matrix[i][j];
                  }
                  groupSums.push(x);
                  subgroupIndex.push(sequence(n));
                  k += x;
              }
  
              // Sort groups…
              if (sortGroups)
                  groupIndex.sort(function (a, b) {
                      return sortGroups(groupSums[a], groupSums[b]);
                  });
  
              // Sort subgroups…
              if (sortSubgroups)
                  subgroupIndex.forEach(function (d, i) {
                      d.sort(function (a, b) {
                          return sortSubgroups(matrix[i][a], matrix[i][b]);
                      });
                  });
  
              // Convert the sum to scaling factor for [0, 2pi].
              // TODO Allow start and end angle to be specified?
              // TODO Allow padding to be specified as percentage?
              k = max$1(0, tau$1 - padAngle * n) / k;
              dx = k ? padAngle : tau$1 / n;
  
              // Compute the start and end angle for each group and subgroup.
              // Note: Opera has a bug reordering object literal properties!
              x = 0, i = -1;
              while (++i < n) {
                  x0 = x, j = -1;
                  while (++j < n) {
                      var di = groupIndex[i],
                              dj = subgroupIndex[di][j],
                              v = matrix[di][dj],
                              a0 = x,
                              a1 = x += v * k;
                      subgroups[dj * n + di] = {
                          index: di,
                          subindex: dj,
                          startAngle: a0,
                          endAngle: a1,
                          value: v
                      };
                  }
                  groups[di] = {
                      index: di,
                      startAngle: x0,
                      endAngle: x,
                      value: groupSums[di]
                  };
                  x += dx;
              }
  
              // Generate chords for each (non-empty) subgroup-subgroup link.
              i = -1;
              while (++i < n) {
                  j = i - 1;
                  while (++j < n) {
                      var source = subgroups[j * n + i],
                              target = subgroups[i * n + j];
                      if (source.value || target.value) {
                          chords.push(source.value < target.value
                                  ? {source: target, target: source}
                          : {source: source, target: target});
                      }
                  }
              }
  
              return sortChords ? chords.sort(sortChords) : chords;
          }
  
          chord.padAngle = function (_) {
              return arguments.length ? (padAngle = max$1(0, _), chord) : padAngle;
          };
  
          chord.sortGroups = function (_) {
              return arguments.length ? (sortGroups = _, chord) : sortGroups;
          };
  
          chord.sortSubgroups = function (_) {
              return arguments.length ? (sortSubgroups = _, chord) : sortSubgroups;
          };
  
          chord.sortChords = function (_) {
              return arguments.length ? (_ == null ? sortChords = null : (sortChords = compareValue(_))._ = _, chord) : sortChords && sortChords._;
          };
  
          return chord;
      }
  
      var slice$2 = Array.prototype.slice;
  
      function constant$5(x) {
          return function () {
              return x;
          };
      }
  
      var pi$2 = Math.PI,
              tau$2 = 2 * pi$2,
              epsilon$1 = 1e-6,
              tauEpsilon = tau$2 - epsilon$1;
  
      function Path() {
          this._x0 = this._y0 = // start of current subpath
                  this._x1 = this._y1 = null; // end of current subpath
          this._ = "";
      }
  
      function path() {
          return new Path;
      }
  
      Path.prototype = path.prototype = {
          constructor: Path,
          moveTo: function (x, y) {
              this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y);
          },
          closePath: function () {
              if (this._x1 !== null) {
                  this._x1 = this._x0, this._y1 = this._y0;
                  this._ += "Z";
              }
          },
          lineTo: function (x, y) {
              this._ += "L" + (this._x1 = +x) + "," + (this._y1 = +y);
          },
          quadraticCurveTo: function (x1, y1, x, y) {
              this._ += "Q" + (+x1) + "," + (+y1) + "," + (this._x1 = +x) + "," + (this._y1 = +y);
          },
          bezierCurveTo: function (x1, y1, x2, y2, x, y) {
              this._ += "C" + (+x1) + "," + (+y1) + "," + (+x2) + "," + (+y2) + "," + (this._x1 = +x) + "," + (this._y1 = +y);
          },
          arcTo: function (x1, y1, x2, y2, r) {
              x1 = +x1, y1 = +y1, x2 = +x2, y2 = +y2, r = +r;
              var x0 = this._x1,
                      y0 = this._y1,
                      x21 = x2 - x1,
                      y21 = y2 - y1,
                      x01 = x0 - x1,
                      y01 = y0 - y1,
                      l01_2 = x01 * x01 + y01 * y01;
  
              // Is the radius negative? Error.
              if (r < 0)
                  throw new Error("negative radius: " + r);
  
              // Is this path empty? Move to (x1,y1).
              if (this._x1 === null) {
                  this._ += "M" + (this._x1 = x1) + "," + (this._y1 = y1);
              }
  
              // Or, is (x1,y1) coincident with (x0,y0)? Do nothing.
              else if (!(l01_2 > epsilon$1))
                  ;
  
              // Or, are (x0,y0), (x1,y1) and (x2,y2) collinear?
              // Equivalently, is (x1,y1) coincident with (x2,y2)?
              // Or, is the radius zero? Line to (x1,y1).
              else if (!(Math.abs(y01 * x21 - y21 * x01) > epsilon$1) || !r) {
                  this._ += "L" + (this._x1 = x1) + "," + (this._y1 = y1);
              }
  
              // Otherwise, draw an arc!
              else {
                  var x20 = x2 - x0,
                          y20 = y2 - y0,
                          l21_2 = x21 * x21 + y21 * y21,
                          l20_2 = x20 * x20 + y20 * y20,
                          l21 = Math.sqrt(l21_2),
                          l01 = Math.sqrt(l01_2),
                          l = r * Math.tan((pi$2 - Math.acos((l21_2 + l01_2 - l20_2) / (2 * l21 * l01))) / 2),
                          t01 = l / l01,
                          t21 = l / l21;
  
                  // If the start tangent is not coincident with (x0,y0), line to.
                  if (Math.abs(t01 - 1) > epsilon$1) {
                      this._ += "L" + (x1 + t01 * x01) + "," + (y1 + t01 * y01);
                  }
  
                  this._ += "A" + r + "," + r + ",0,0," + (+(y01 * x20 > x01 * y20)) + "," + (this._x1 = x1 + t21 * x21) + "," + (this._y1 = y1 + t21 * y21);
              }
          },
          arc: function (x, y, r, a0, a1, ccw) {
              x = +x, y = +y, r = +r, ccw = !!ccw;
              var dx = r * Math.cos(a0),
                      dy = r * Math.sin(a0),
                      x0 = x + dx,
                      y0 = y + dy,
                      cw = 1 ^ ccw,
                      da = ccw ? a0 - a1 : a1 - a0;
  
              // Is the radius negative? Error.
              if (r < 0)
                  throw new Error("negative radius: " + r);
  
              // Is this path empty? Move to (x0,y0).
              if (this._x1 === null) {
                  this._ += "M" + x0 + "," + y0;
              }
  
              // Or, is (x0,y0) not coincident with the previous point? Line to (x0,y0).
              else if (Math.abs(this._x1 - x0) > epsilon$1 || Math.abs(this._y1 - y0) > epsilon$1) {
                  this._ += "L" + x0 + "," + y0;
              }
  
              // Is this arc empty? We’re done.
              if (!r)
                  return;
  
              // Does the angle go the wrong way? Flip the direction.
              if (da < 0)
                  da = da % tau$2 + tau$2;
  
              // Is this a complete circle? Draw two arcs to complete the circle.
              if (da > tauEpsilon) {
                  this._ += "A" + r + "," + r + ",0,1," + cw + "," + (x - dx) + "," + (y - dy) + "A" + r + "," + r + ",0,1," + cw + "," + (this._x1 = x0) + "," + (this._y1 = y0);
              }
  
              // Is this arc non-empty? Draw an arc!
              else if (da > epsilon$1) {
                  this._ += "A" + r + "," + r + ",0," + (+(da >= pi$2)) + "," + cw + "," + (this._x1 = x + r * Math.cos(a1)) + "," + (this._y1 = y + r * Math.sin(a1));
              }
          },
          rect: function (x, y, w, h) {
              this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y) + "h" + (+w) + "v" + (+h) + "h" + (-w) + "Z";
          },
          toString: function () {
              return this._;
          }
      };
  
      function defaultSource(d) {
          return d.source;
      }
  
      function defaultTarget(d) {
          return d.target;
      }
  
      function defaultRadius(d) {
          return d.radius;
      }
  
      function defaultStartAngle(d) {
          return d.startAngle;
      }
  
      function defaultEndAngle(d) {
          return d.endAngle;
      }
  
      function ribbon() {
          var source = defaultSource,
                  target = defaultTarget,
                  radius = defaultRadius,
                  startAngle = defaultStartAngle,
                  endAngle = defaultEndAngle,
                  context = null;
  
          function ribbon() {
              var buffer,
                      argv = slice$2.call(arguments),
                      s = source.apply(this, argv),
                      t = target.apply(this, argv),
                      sr = +radius.apply(this, (argv[0] = s, argv)),
                      sa0 = startAngle.apply(this, argv) - halfPi$1,
                      sa1 = endAngle.apply(this, argv) - halfPi$1,
                      sx0 = sr * cos(sa0),
                      sy0 = sr * sin(sa0),
                      tr = +radius.apply(this, (argv[0] = t, argv)),
                      ta0 = startAngle.apply(this, argv) - halfPi$1,
                      ta1 = endAngle.apply(this, argv) - halfPi$1;
  
              if (!context)
                  context = buffer = path();
  
              context.moveTo(sx0, sy0);
              context.arc(0, 0, sr, sa0, sa1);
              if (sa0 !== ta0 || sa1 !== ta1) { // TODO sr !== tr?
                  context.quadraticCurveTo(0, 0, tr * cos(ta0), tr * sin(ta0));
                  context.arc(0, 0, tr, ta0, ta1);
              }
              context.quadraticCurveTo(0, 0, sx0, sy0);
              context.closePath();
  
              if (buffer)
                  return context = null, buffer + "" || null;
          }
  
          ribbon.radius = function (_) {
              return arguments.length ? (radius = typeof _ === "function" ? _ : constant$5(+_), ribbon) : radius;
          };
  
          ribbon.startAngle = function (_) {
              return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$5(+_), ribbon) : startAngle;
          };
  
          ribbon.endAngle = function (_) {
              return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$5(+_), ribbon) : endAngle;
          };
  
          ribbon.source = function (_) {
              return arguments.length ? (source = _, ribbon) : source;
          };
  
          ribbon.target = function (_) {
              return arguments.length ? (target = _, ribbon) : target;
          };
  
          ribbon.context = function (_) {
              return arguments.length ? ((context = _ == null ? null : _), ribbon) : context;
          };
  
          return ribbon;
      }
  
      var prefix = "$";
  
      function Map() {}
  
      Map.prototype = map$1.prototype = {
          constructor: Map,
          has: function (key) {
              return (prefix + key) in this;
          },
          get: function (key) {
              return this[prefix + key];
          },
          set: function (key, value) {
              this[prefix + key] = value;
              return this;
          },
          remove: function (key) {
              var property = prefix + key;
              return property in this && delete this[property];
          },
          clear: function () {
              for (var property in this)
                  if (property[0] === prefix)
                      delete this[property];
          },
          keys: function () {
              var keys = [];
              for (var property in this)
                  if (property[0] === prefix)
                      keys.push(property.slice(1));
              return keys;
          },
          values: function () {
              var values = [];
              for (var property in this)
                  if (property[0] === prefix)
                      values.push(this[property]);
              return values;
          },
          entries: function () {
              var entries = [];
              for (var property in this)
                  if (property[0] === prefix)
                      entries.push({key: property.slice(1), value: this[property]});
              return entries;
          },
          size: function () {
              var size = 0;
              for (var property in this)
                  if (property[0] === prefix)
                      ++size;
              return size;
          },
          empty: function () {
              for (var property in this)
                  if (property[0] === prefix)
                      return false;
              return true;
          },
          each: function (f) {
              for (var property in this)
                  if (property[0] === prefix)
                      f(this[property], property.slice(1), this);
          }
      };
  
      function map$1(object, f) {
          var map = new Map;
  
          // Copy constructor.
          if (object instanceof Map)
              object.each(function (value, key) {
                  map.set(key, value);
              });
  
          // Index array by numeric index or specified key function.
          else if (Array.isArray(object)) {
              var i = -1,
                      n = object.length,
                      o;
  
              if (f == null)
                  while (++i < n)
                      map.set(i, object[i]);
              else
                  while (++i < n)
                      map.set(f(o = object[i], i, object), o);
          }
  
          // Convert object to map.
          else if (object)
              for (var key in object)
                  map.set(key, object[key]);
  
          return map;
      }
  
      function nest() {
          var keys = [],
                  sortKeys = [],
                  sortValues,
                  rollup,
                  nest;
  
          function apply(array, depth, createResult, setResult) {
              if (depth >= keys.length) {
                  if (sortValues != null)
                      array.sort(sortValues);
                  return rollup != null ? rollup(array) : array;
              }
  
              var i = -1,
                      n = array.length,
                      key = keys[depth++],
                      keyValue,
                      value,
                      valuesByKey = map$1(),
                      values,
                      result = createResult();
  
              while (++i < n) {
                  if (values = valuesByKey.get(keyValue = key(value = array[i]) + "")) {
                      values.push(value);
                  } else {
                      valuesByKey.set(keyValue, [value]);
                  }
              }
  
              valuesByKey.each(function (values, key) {
                  setResult(result, key, apply(values, depth, createResult, setResult));
              });
  
              return result;
          }
  
          function entries(map, depth) {
              if (++depth > keys.length)
                  return map;
              var array, sortKey = sortKeys[depth - 1];
              if (rollup != null && depth >= keys.length)
                  array = map.entries();
              else
                  array = [], map.each(function (v, k) {
                      array.push({key: k, values: entries(v, depth)});
                  });
              return sortKey != null ? array.sort(function (a, b) {
                  return sortKey(a.key, b.key);
              }) : array;
          }
  
          return nest = {
              object: function (array) {
                  return apply(array, 0, createObject, setObject);
              },
              map: function (array) {
                  return apply(array, 0, createMap, setMap);
              },
              entries: function (array) {
                  return entries(apply(array, 0, createMap, setMap), 0);
              },
              key: function (d) {
                  keys.push(d);
                  return nest;
              },
              sortKeys: function (order) {
                  sortKeys[keys.length - 1] = order;
                  return nest;
              },
              sortValues: function (order) {
                  sortValues = order;
                  return nest;
              },
              rollup: function (f) {
                  rollup = f;
                  return nest;
              }
          };
      }
  
      function createObject() {
          return {};
      }
  
      function setObject(object, key, value) {
          object[key] = value;
      }
  
      function createMap() {
          return map$1();
      }
  
      function setMap(map, key, value) {
          map.set(key, value);
      }
  
      function Set() {}
  
      var proto = map$1.prototype;
  
      Set.prototype = set$2.prototype = {
          constructor: Set,
          has: proto.has,
          add: function (value) {
              value += "";
              this[prefix + value] = value;
              return this;
          },
          remove: proto.remove,
          clear: proto.clear,
          values: proto.keys,
          size: proto.size,
          empty: proto.empty,
          each: proto.each
      };
  
      function set$2(object, f) {
          var set = new Set;
  
          // Copy constructor.
          if (object instanceof Set)
              object.each(function (value) {
                  set.add(value);
              });
  
          // Otherwise, assume it’s an array.
          else if (object) {
              var i = -1, n = object.length;
              if (f == null)
                  while (++i < n)
                      set.add(object[i]);
              else
                  while (++i < n)
                      set.add(f(object[i], i, object));
          }
  
          return set;
      }
  
      function keys(map) {
          var keys = [];
          for (var key in map)
              keys.push(key);
          return keys;
      }
  
      function values(map) {
          var values = [];
          for (var key in map)
              values.push(map[key]);
          return values;
      }
  
      function entries(map) {
          var entries = [];
          for (var key in map)
              entries.push({key: key, value: map[key]});
          return entries;
      }
  
      var array$2 = Array.prototype;
  
      var slice$3 = array$2.slice;
  
      function ascending$2(a, b) {
          return a - b;
      }
  
      function area(ring) {
          var i = 0, n = ring.length, area = ring[n - 1][1] * ring[0][0] - ring[n - 1][0] * ring[0][1];
          while (++i < n)
              area += ring[i - 1][1] * ring[i][0] - ring[i - 1][0] * ring[i][1];
          return area;
      }
  
      function constant$6(x) {
          return function () {
              return x;
          };
      }
  
      function contains(ring, hole) {
          var i = -1, n = hole.length, c;
          while (++i < n)
              if (c = ringContains(ring, hole[i]))
                  return c;
          return 0;
      }
  
      function ringContains(ring, point) {
          var x = point[0], y = point[1], contains = -1;
          for (var i = 0, n = ring.length, j = n - 1; i < n; j = i++) {
              var pi = ring[i], xi = pi[0], yi = pi[1], pj = ring[j], xj = pj[0], yj = pj[1];
              if (segmentContains(pi, pj, point))
                  return 0;
              if (((yi > y) !== (yj > y)) && ((x < (xj - xi) * (y - yi) / (yj - yi) + xi)))
                  contains = -contains;
          }
          return contains;
      }
  
      function segmentContains(a, b, c) {
          var i;
          return collinear(a, b, c) && within(a[i = +(a[0] === b[0])], c[i], b[i]);
      }
  
      function collinear(a, b, c) {
          return (b[0] - a[0]) * (c[1] - a[1]) === (c[0] - a[0]) * (b[1] - a[1]);
      }
  
      function within(p, q, r) {
          return p <= q && q <= r || r <= q && q <= p;
      }
  
      function noop$1() {}
  
      var cases = [
          [],
          [[[1.0, 1.5], [0.5, 1.0]]],
          [[[1.5, 1.0], [1.0, 1.5]]],
          [[[1.5, 1.0], [0.5, 1.0]]],
          [[[1.0, 0.5], [1.5, 1.0]]],
          [[[1.0, 1.5], [0.5, 1.0]], [[1.0, 0.5], [1.5, 1.0]]],
          [[[1.0, 0.5], [1.0, 1.5]]],
          [[[1.0, 0.5], [0.5, 1.0]]],
          [[[0.5, 1.0], [1.0, 0.5]]],
          [[[1.0, 1.5], [1.0, 0.5]]],
          [[[0.5, 1.0], [1.0, 0.5]], [[1.5, 1.0], [1.0, 1.5]]],
          [[[1.5, 1.0], [1.0, 0.5]]],
          [[[0.5, 1.0], [1.5, 1.0]]],
          [[[1.0, 1.5], [1.5, 1.0]]],
          [[[0.5, 1.0], [1.0, 1.5]]],
          []
      ];
  
      function contours() {
          var dx = 1,
                  dy = 1,
                  threshold = thresholdSturges,
                  smooth = smoothLinear;
  
          function contours(values) {
              var tz = threshold(values);
  
              // Convert number of thresholds into uniform thresholds.
              if (!Array.isArray(tz)) {
                  var domain = extent(values), start = domain[0], stop = domain[1];
                  tz = tickStep(start, stop, tz);
                  tz = sequence(Math.floor(start / tz) * tz, Math.floor(stop / tz) * tz, tz);
              } else {
                  tz = tz.slice().sort(ascending$2);
              }
  
              return tz.map(function (value) {
                  return contour(values, value);
              });
          }
  
          // Accumulate, smooth contour rings, assign holes to exterior rings.
          // Based on https://github.com/mbostock/shapefile/blob/v0.6.2/shp/polygon.js
          function contour(values, value) {
              var polygons = [],
                      holes = [];
  
              isorings(values, value, function (ring) {
                  smooth(ring, values, value);
                  if (area(ring) > 0)
                      polygons.push([ring]);
                  else
                      holes.push(ring);
              });
  
              holes.forEach(function (hole) {
                  for (var i = 0, n = polygons.length, polygon; i < n; ++i) {
                      if (contains((polygon = polygons[i])[0], hole) !== -1) {
                          polygon.push(hole);
                          return;
                      }
                  }
              });
  
              return {
                  type: "MultiPolygon",
                  value: value,
                  coordinates: polygons
              };
          }
  
          // Marching squares with isolines stitched into rings.
          // Based on https://github.com/topojson/topojson-client/blob/v3.0.0/src/stitch.js
          function isorings(values, value, callback) {
              var fragmentByStart = new Array,
                      fragmentByEnd = new Array,
                      x, y, t0, t1, t2, t3;
  
              // Special case for the first row (y = -1, t2 = t3 = 0).
              x = y = -1;
              t1 = values[0] >= value;
              cases[t1 << 1].forEach(stitch);
              while (++x < dx - 1) {
                  t0 = t1, t1 = values[x + 1] >= value;
                  cases[t0 | t1 << 1].forEach(stitch);
              }
              cases[t1 << 0].forEach(stitch);
  
              // General case for the intermediate rows.
              while (++y < dy - 1) {
                  x = -1;
                  t1 = values[y * dx + dx] >= value;
                  t2 = values[y * dx] >= value;
                  cases[t1 << 1 | t2 << 2].forEach(stitch);
                  while (++x < dx - 1) {
                      t0 = t1, t1 = values[y * dx + dx + x + 1] >= value;
                      t3 = t2, t2 = values[y * dx + x + 1] >= value;
                      cases[t0 | t1 << 1 | t2 << 2 | t3 << 3].forEach(stitch);
                  }
                  cases[t1 | t2 << 3].forEach(stitch);
              }
  
              // Special case for the last row (y = dy - 1, t0 = t1 = 0).
              x = -1;
              t2 = values[y * dx] >= value;
              cases[t2 << 2].forEach(stitch);
              while (++x < dx - 1) {
                  t3 = t2, t2 = values[y * dx + x + 1] >= value;
                  cases[t2 << 2 | t3 << 3].forEach(stitch);
              }
              cases[t2 << 3].forEach(stitch);
  
              function stitch(line) {
                  var start = [line[0][0] + x, line[0][1] + y],
                          end = [line[1][0] + x, line[1][1] + y],
                          startIndex = index(start),
                          endIndex = index(end),
                          f, g;
                  if (f = fragmentByEnd[startIndex]) {
                      if (g = fragmentByStart[endIndex]) {
                          delete fragmentByEnd[f.end];
                          delete fragmentByStart[g.start];
                          if (f === g) {
                              f.ring.push(end);
                              callback(f.ring);
                          } else {
                              fragmentByStart[f.start] = fragmentByEnd[g.end] = {start: f.start, end: g.end, ring: f.ring.concat(g.ring)};
                          }
                      } else {
                          delete fragmentByEnd[f.end];
                          f.ring.push(end);
                          fragmentByEnd[f.end = endIndex] = f;
                      }
                  } else if (f = fragmentByStart[endIndex]) {
                      if (g = fragmentByEnd[startIndex]) {
                          delete fragmentByStart[f.start];
                          delete fragmentByEnd[g.end];
                          if (f === g) {
                              f.ring.push(end);
                              callback(f.ring);
                          } else {
                              fragmentByStart[g.start] = fragmentByEnd[f.end] = {start: g.start, end: f.end, ring: g.ring.concat(f.ring)};
                          }
                      } else {
                          delete fragmentByStart[f.start];
                          f.ring.unshift(start);
                          fragmentByStart[f.start = startIndex] = f;
                      }
                  } else {
                      fragmentByStart[startIndex] = fragmentByEnd[endIndex] = {start: startIndex, end: endIndex, ring: [start, end]};
                  }
              }
          }
  
          function index(point) {
              return point[0] * 2 + point[1] * (dx + 1) * 4;
          }
  
          function smoothLinear(ring, values, value) {
              ring.forEach(function (point) {
                  var x = point[0],
                          y = point[1],
                          xt = x | 0,
                          yt = y | 0,
                          v0,
                          v1 = values[yt * dx + xt];
                  if (x > 0 && x < dx && xt === x) {
                      v0 = values[yt * dx + xt - 1];
                      point[0] = x + (value - v0) / (v1 - v0) - 0.5;
                  }
                  if (y > 0 && y < dy && yt === y) {
                      v0 = values[(yt - 1) * dx + xt];
                      point[1] = y + (value - v0) / (v1 - v0) - 0.5;
                  }
              });
          }
  
          contours.contour = contour;
  
          contours.size = function (_) {
              if (!arguments.length)
                  return [dx, dy];
              var _0 = Math.ceil(_[0]), _1 = Math.ceil(_[1]);
              if (!(_0 > 0) || !(_1 > 0))
                  throw new Error("invalid size");
              return dx = _0, dy = _1, contours;
          };
  
          contours.thresholds = function (_) {
              return arguments.length ? (threshold = typeof _ === "function" ? _ : Array.isArray(_) ? constant$6(slice$3.call(_)) : constant$6(_), contours) : threshold;
          };
  
          contours.smooth = function (_) {
              return arguments.length ? (smooth = _ ? smoothLinear : noop$1, contours) : smooth === smoothLinear;
          };
  
          return contours;
      }
  
  // TODO Optimize edge cases.
  // TODO Optimize index calculation.
  // TODO Optimize arguments.
      function blurX(source, target, r) {
          var n = source.width,
                  m = source.height,
                  w = (r << 1) + 1;
          for (var j = 0; j < m; ++j) {
              for (var i = 0, sr = 0; i < n + r; ++i) {
                  if (i < n) {
                      sr += source.data[i + j * n];
                  }
                  if (i >= r) {
                      if (i >= w) {
                          sr -= source.data[i - w + j * n];
                      }
                      target.data[i - r + j * n] = sr / Math.min(i + 1, n - 1 + w - i, w);
                  }
              }
          }
      }
  
  // TODO Optimize edge cases.
  // TODO Optimize index calculation.
  // TODO Optimize arguments.
      function blurY(source, target, r) {
          var n = source.width,
                  m = source.height,
                  w = (r << 1) + 1;
          for (var i = 0; i < n; ++i) {
              for (var j = 0, sr = 0; j < m + r; ++j) {
                  if (j < m) {
                      sr += source.data[i + j * n];
                  }
                  if (j >= r) {
                      if (j >= w) {
                          sr -= source.data[i + (j - w) * n];
                      }
                      target.data[i + (j - r) * n] = sr / Math.min(j + 1, m - 1 + w - j, w);
                  }
              }
          }
      }
  
      function defaultX(d) {
          return d[0];
      }
  
      function defaultY(d) {
          return d[1];
      }
  
      function defaultWeight() {
          return 1;
      }
  
      function density() {
          var x = defaultX,
                  y = defaultY,
                  weight = defaultWeight,
                  dx = 960,
                  dy = 500,
                  r = 20, // blur radius
                  k = 2, // log2(grid cell size)
                  o = r * 3, // grid offset, to pad for blur
                  n = (dx + o * 2) >> k, // grid width
                  m = (dy + o * 2) >> k, // grid height
                  threshold = constant$6(20);
  
          function density(data) {
              var values0 = new Float32Array(n * m),
                      values1 = new Float32Array(n * m);
  
              data.forEach(function (d, i, data) {
                  var xi = (+x(d, i, data) + o) >> k,
                          yi = (+y(d, i, data) + o) >> k,
                          wi = +weight(d, i, data);
                  if (xi >= 0 && xi < n && yi >= 0 && yi < m) {
                      values0[xi + yi * n] += wi;
                  }
              });
  
              // TODO Optimize.
              blurX({width: n, height: m, data: values0}, {width: n, height: m, data: values1}, r >> k);
              blurY({width: n, height: m, data: values1}, {width: n, height: m, data: values0}, r >> k);
              blurX({width: n, height: m, data: values0}, {width: n, height: m, data: values1}, r >> k);
              blurY({width: n, height: m, data: values1}, {width: n, height: m, data: values0}, r >> k);
              blurX({width: n, height: m, data: values0}, {width: n, height: m, data: values1}, r >> k);
              blurY({width: n, height: m, data: values1}, {width: n, height: m, data: values0}, r >> k);
  
              var tz = threshold(values0);
  
              // Convert number of thresholds into uniform thresholds.
              if (!Array.isArray(tz)) {
                  var stop = max(values0);
                  tz = tickStep(0, stop, tz);
                  tz = sequence(0, Math.floor(stop / tz) * tz, tz);
                  tz.shift();
              }
  
              return contours()
                      .thresholds(tz)
                      .size([n, m])
                      (values0)
                      .map(transform);
          }
  
          function transform(geometry) {
              geometry.value *= Math.pow(2, -2 * k); // Density in points per square pixel.
              geometry.coordinates.forEach(transformPolygon);
              return geometry;
          }
  
          function transformPolygon(coordinates) {
              coordinates.forEach(transformRing);
          }
  
          function transformRing(coordinates) {
              coordinates.forEach(transformPoint);
          }
  
          // TODO Optimize.
          function transformPoint(coordinates) {
              coordinates[0] = coordinates[0] * Math.pow(2, k) - o;
              coordinates[1] = coordinates[1] * Math.pow(2, k) - o;
          }
  
          function resize() {
              o = r * 3;
              n = (dx + o * 2) >> k;
              m = (dy + o * 2) >> k;
              return density;
          }
  
          density.x = function (_) {
              return arguments.length ? (x = typeof _ === "function" ? _ : constant$6(+_), density) : x;
          };
  
          density.y = function (_) {
              return arguments.length ? (y = typeof _ === "function" ? _ : constant$6(+_), density) : y;
          };
  
          density.weight = function (_) {
              return arguments.length ? (weight = typeof _ === "function" ? _ : constant$6(+_), density) : weight;
          };
  
          density.size = function (_) {
              if (!arguments.length)
                  return [dx, dy];
              var _0 = Math.ceil(_[0]), _1 = Math.ceil(_[1]);
              if (!(_0 >= 0) && !(_0 >= 0))
                  throw new Error("invalid size");
              return dx = _0, dy = _1, resize();
          };
  
          density.cellSize = function (_) {
              if (!arguments.length)
                  return 1 << k;
              if (!((_ = +_) >= 1))
                  throw new Error("invalid cell size");
              return k = Math.floor(Math.log(_) / Math.LN2), resize();
          };
  
          density.thresholds = function (_) {
              return arguments.length ? (threshold = typeof _ === "function" ? _ : Array.isArray(_) ? constant$6(slice$3.call(_)) : constant$6(_), density) : threshold;
          };
  
          density.bandwidth = function (_) {
              if (!arguments.length)
                  return Math.sqrt(r * (r + 1));
              if (!((_ = +_) >= 0))
                  throw new Error("invalid bandwidth");
              return r = Math.round((Math.sqrt(4 * _ * _ + 1) - 1) / 2), resize();
          };
  
          return density;
      }
  
      var EOL = {},
              EOF = {},
              QUOTE = 34,
              NEWLINE = 10,
              RETURN = 13;
  
      function objectConverter(columns) {
          return new Function("d", "return {" + columns.map(function (name, i) {
              return JSON.stringify(name) + ": d[" + i + "] || \"\"";
          }).join(",") + "}");
      }
  
      function customConverter(columns, f) {
          var object = objectConverter(columns);
          return function (row, i) {
              return f(object(row), i, columns);
          };
      }
  
  // Compute unique columns in order of discovery.
      function inferColumns(rows) {
          var columnSet = Object.create(null),
                  columns = [];
  
          rows.forEach(function (row) {
              for (var column in row) {
                  if (!(column in columnSet)) {
                      columns.push(columnSet[column] = column);
                  }
              }
          });
  
          return columns;
      }
  
      function pad(value, width) {
          var s = value + "", length = s.length;
          return length < width ? new Array(width - length + 1).join(0) + s : s;
      }
  
      function formatYear(year) {
          return year < 0 ? "-" + pad(-year, 6)
                  : year > 9999 ? "+" + pad(year, 6)
                  : pad(year, 4);
      }
  
      function formatDate(date) {
          var hours = date.getUTCHours(),
                  minutes = date.getUTCMinutes(),
                  seconds = date.getUTCSeconds(),
                  milliseconds = date.getUTCMilliseconds();
          return isNaN(date) ? "Invalid Date"
                  : formatYear(date.getUTCFullYear()) + "-" + pad(date.getUTCMonth() + 1, 2) + "-" + pad(date.getUTCDate(), 2)
                  + (milliseconds ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + ":" + pad(seconds, 2) + "." + pad(milliseconds, 3) + "Z"
                          : seconds ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + ":" + pad(seconds, 2) + "Z"
                          : minutes || hours ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + "Z"
                          : "");
      }
  
      function dsvFormat(delimiter) {
          var reFormat = new RegExp("[\"" + delimiter + "\n\r]"),
                  DELIMITER = delimiter.charCodeAt(0);
  
          function parse(text, f) {
              var convert, columns, rows = parseRows(text, function (row, i) {
                  if (convert)
                      return convert(row, i - 1);
                  columns = row, convert = f ? customConverter(row, f) : objectConverter(row);
              });
              rows.columns = columns || [];
              return rows;
          }
  
          function parseRows(text, f) {
              var rows = [], // output rows
                      N = text.length,
                      I = 0, // current character index
                      n = 0, // current line number
                      t, // current token
                      eof = N <= 0, // current token followed by EOF?
                      eol = false; // current token followed by EOL?
  
              // Strip the trailing newline.
              if (text.charCodeAt(N - 1) === NEWLINE)
                  --N;
              if (text.charCodeAt(N - 1) === RETURN)
                  --N;
  
              function token() {
                  if (eof)
                      return EOF;
                  if (eol)
                      return eol = false, EOL;
  
                  // Unescape quotes.
                  var i, j = I, c;
                  if (text.charCodeAt(j) === QUOTE) {
                      while (I++ < N && text.charCodeAt(I) !== QUOTE || text.charCodeAt(++I) === QUOTE)
                          ;
                      if ((i = I) >= N)
                          eof = true;
                      else if ((c = text.charCodeAt(I++)) === NEWLINE)
                          eol = true;
                      else if (c === RETURN) {
                          eol = true;
                          if (text.charCodeAt(I) === NEWLINE)
                              ++I;
                      }
                      return text.slice(j + 1, i - 1).replace(/""/g, "\"");
                  }
  
                  // Find next delimiter or newline.
                  while (I < N) {
                      if ((c = text.charCodeAt(i = I++)) === NEWLINE)
                          eol = true;
                      else if (c === RETURN) {
                          eol = true;
                          if (text.charCodeAt(I) === NEWLINE)
                              ++I;
                      } else if (c !== DELIMITER)
                          continue;
                      return text.slice(j, i);
                  }
  
                  // Return last token before EOF.
                  return eof = true, text.slice(j, N);
              }
  
              while ((t = token()) !== EOF) {
                  var row = [];
                  while (t !== EOL && t !== EOF)
                      row.push(t), t = token();
                  if (f && (row = f(row, n++)) == null)
                      continue;
                  rows.push(row);
              }
  
              return rows;
          }
  
          function preformatBody(rows, columns) {
              return rows.map(function (row) {
                  return columns.map(function (column) {
                      return formatValue(row[column]);
                  }).join(delimiter);
              });
          }
  
          function format(rows, columns) {
              if (columns == null)
                  columns = inferColumns(rows);
              return [columns.map(formatValue).join(delimiter)].concat(preformatBody(rows, columns)).join("\n");
          }
  
          function formatBody(rows, columns) {
              if (columns == null)
                  columns = inferColumns(rows);
              return preformatBody(rows, columns).join("\n");
          }
  
          function formatRows(rows) {
              return rows.map(formatRow).join("\n");
          }
  
          function formatRow(row) {
              return row.map(formatValue).join(delimiter);
          }
  
          function formatValue(value) {
              return value == null ? ""
                      : value instanceof Date ? formatDate(value)
                      : reFormat.test(value += "") ? "\"" + value.replace(/"/g, "\"\"") + "\""
                      : value;
          }
  
          return {
              parse: parse,
              parseRows: parseRows,
              format: format,
              formatBody: formatBody,
              formatRows: formatRows,
              formatRow: formatRow,
              formatValue: formatValue
          };
      }
  
      var csv = dsvFormat(",");
  
      var csvParse = csv.parse;
      var csvParseRows = csv.parseRows;
      var csvFormat = csv.format;
      var csvFormatBody = csv.formatBody;
      var csvFormatRows = csv.formatRows;
      var csvFormatRow = csv.formatRow;
      var csvFormatValue = csv.formatValue;
  
      var tsv = dsvFormat("\t");
  
      var tsvParse = tsv.parse;
      var tsvParseRows = tsv.parseRows;
      var tsvFormat = tsv.format;
      var tsvFormatBody = tsv.formatBody;
      var tsvFormatRows = tsv.formatRows;
      var tsvFormatRow = tsv.formatRow;
      var tsvFormatValue = tsv.formatValue;
  
      function autoType(object) {
          for (var key in object) {
              var value = object[key].trim(), number, m;
              if (!value)
                  value = null;
              else if (value === "true")
                  value = true;
              else if (value === "false")
                  value = false;
              else if (value === "NaN")
                  value = NaN;
              else if (!isNaN(number = +value))
                  value = number;
              else if (m = value.match(/^([-+]\d{2})?\d{4}(-\d{2}(-\d{2})?)?(T\d{2}:\d{2}(:\d{2}(\.\d{3})?)?(Z|[-+]\d{2}:\d{2})?)?$/)) {
                  if (fixtz && !!m[4] && !m[7])
                      value = value.replace(/-/g, "/").replace(/T/, " ");
                  value = new Date(value);
              } else
                  continue;
              object[key] = value;
          }
          return object;
      }
  
  // https://github.com/d3/d3-dsv/issues/45
      var fixtz = new Date("2019-01-01T00:00").getHours() || new Date("2019-07-01T00:00").getHours();
  
      function responseBlob(response) {
          if (!response.ok)
              throw new Error(response.status + " " + response.statusText);
          return response.blob();
      }
  
      function blob(input, init) {
          return fetch(input, init).then(responseBlob);
      }
  
      function responseArrayBuffer(response) {
          if (!response.ok)
              throw new Error(response.status + " " + response.statusText);
          return response.arrayBuffer();
      }
  
      function buffer(input, init) {
          return fetch(input, init).then(responseArrayBuffer);
      }
  
      function responseText(response) {
          if (!response.ok)
              throw new Error(response.status + " " + response.statusText);
          return response.text();
      }
  
      function text(input, init) {
          return fetch(input, init).then(responseText);
      }
  
      function dsvParse(parse) {
          return function (input, init, row) {
              if (arguments.length === 2 && typeof init === "function")
                  row = init, init = undefined;
              return text(input, init).then(function (response) {
                  return parse(response, row);
              });
          };
      }
  
      function dsv(delimiter, input, init, row) {
          if (arguments.length === 3 && typeof init === "function")
              row = init, init = undefined;
          var format = dsvFormat(delimiter);
          return text(input, init).then(function (response) {
              return format.parse(response, row);
          });
      }
  
      var csv$1 = dsvParse(csvParse);
      var tsv$1 = dsvParse(tsvParse);
  
      function image(input, init) {
          return new Promise(function (resolve, reject) {
              var image = new Image;
              for (var key in init)
                  image[key] = init[key];
              image.onerror = reject;
              image.onload = function () {
                  resolve(image);
              };
              image.src = input;
          });
      }
  
      function responseJson(response) {
          if (!response.ok)
              throw new Error(response.status + " " + response.statusText);
          return response.json();
      }
  
      function json(input, init) {
          return fetch(input, init).then(responseJson);
      }
  
      function parser(type) {
          return function (input, init) {
              return text(input, init).then(function (text) {
                  return (new DOMParser).parseFromString(text, type);
              });
          };
      }
  
      var xml = parser("application/xml");
  
      var html = parser("text/html");
  
      var svg = parser("image/svg+xml");
  
      function center$1(x, y) {
          var nodes;
  
          if (x == null)
              x = 0;
          if (y == null)
              y = 0;
  
          function force() {
              var i,
                      n = nodes.length,
                      node,
                      sx = 0,
                      sy = 0;
  
              for (i = 0; i < n; ++i) {
                  node = nodes[i], sx += node.x, sy += node.y;
              }
  
              for (sx = sx / n - x, sy = sy / n - y, i = 0; i < n; ++i) {
                  node = nodes[i], node.x -= sx, node.y -= sy;
              }
          }
  
          force.initialize = function (_) {
              nodes = _;
          };
  
          force.x = function (_) {
              return arguments.length ? (x = +_, force) : x;
          };
  
          force.y = function (_) {
              return arguments.length ? (y = +_, force) : y;
          };
  
          return force;
      }
  
      function constant$7(x) {
          return function () {
              return x;
          };
      }
  
      function jiggle() {
          return (Math.random() - 0.5) * 1e-6;
      }
  
      function tree_add(d) {
          var x = +this._x.call(null, d),
                  y = +this._y.call(null, d);
          return add(this.cover(x, y), x, y, d);
      }
  
      function add(tree, x, y, d) {
          if (isNaN(x) || isNaN(y))
              return tree; // ignore invalid points
  
          var parent,
                  node = tree._root,
                  leaf = {data: d},
                  x0 = tree._x0,
                  y0 = tree._y0,
                  x1 = tree._x1,
                  y1 = tree._y1,
                  xm,
                  ym,
                  xp,
                  yp,
                  right,
                  bottom,
                  i,
                  j;
  
          // If the tree is empty, initialize the root as a leaf.
          if (!node)
              return tree._root = leaf, tree;
  
          // Find the existing leaf for the new point, or add it.
          while (node.length) {
              if (right = x >= (xm = (x0 + x1) / 2))
                  x0 = xm;
              else
                  x1 = xm;
              if (bottom = y >= (ym = (y0 + y1) / 2))
                  y0 = ym;
              else
                  y1 = ym;
              if (parent = node, !(node = node[i = bottom << 1 | right]))
                  return parent[i] = leaf, tree;
          }
  
          // Is the new point is exactly coincident with the existing point?
          xp = +tree._x.call(null, node.data);
          yp = +tree._y.call(null, node.data);
          if (x === xp && y === yp)
              return leaf.next = node, parent ? parent[i] = leaf : tree._root = leaf, tree;
  
          // Otherwise, split the leaf node until the old and new point are separated.
          do {
              parent = parent ? parent[i] = new Array(4) : tree._root = new Array(4);
              if (right = x >= (xm = (x0 + x1) / 2))
                  x0 = xm;
              else
                  x1 = xm;
              if (bottom = y >= (ym = (y0 + y1) / 2))
                  y0 = ym;
              else
                  y1 = ym;
          } while ((i = bottom << 1 | right) === (j = (yp >= ym) << 1 | (xp >= xm)));
          return parent[j] = node, parent[i] = leaf, tree;
      }
  
      function addAll(data) {
          var d, i, n = data.length,
                  x,
                  y,
                  xz = new Array(n),
                  yz = new Array(n),
                  x0 = Infinity,
                  y0 = Infinity,
                  x1 = -Infinity,
                  y1 = -Infinity;
  
          // Compute the points and their extent.
          for (i = 0; i < n; ++i) {
              if (isNaN(x = +this._x.call(null, d = data[i])) || isNaN(y = +this._y.call(null, d)))
                  continue;
              xz[i] = x;
              yz[i] = y;
              if (x < x0)
                  x0 = x;
              if (x > x1)
                  x1 = x;
              if (y < y0)
                  y0 = y;
              if (y > y1)
                  y1 = y;
          }
  
          // If there were no (valid) points, abort.
          if (x0 > x1 || y0 > y1)
              return this;
  
          // Expand the tree to cover the new points.
          this.cover(x0, y0).cover(x1, y1);
  
          // Add the new points.
          for (i = 0; i < n; ++i) {
              add(this, xz[i], yz[i], data[i]);
          }
  
          return this;
      }
  
      function tree_cover(x, y) {
          if (isNaN(x = +x) || isNaN(y = +y))
              return this; // ignore invalid points
  
          var x0 = this._x0,
                  y0 = this._y0,
                  x1 = this._x1,
                  y1 = this._y1;
  
          // If the quadtree has no extent, initialize them.
          // Integer extent are necessary so that if we later double the extent,
          // the existing quadrant boundaries don’t change due to floating point error!
          if (isNaN(x0)) {
              x1 = (x0 = Math.floor(x)) + 1;
              y1 = (y0 = Math.floor(y)) + 1;
          }
  
          // Otherwise, double repeatedly to cover.
          else {
              var z = x1 - x0,
                      node = this._root,
                      parent,
                      i;
  
              while (x0 > x || x >= x1 || y0 > y || y >= y1) {
                  i = (y < y0) << 1 | (x < x0);
                  parent = new Array(4), parent[i] = node, node = parent, z *= 2;
                  switch (i) {
                      case 0:
                          x1 = x0 + z, y1 = y0 + z;
                          break;
                      case 1:
                          x0 = x1 - z, y1 = y0 + z;
                          break;
                      case 2:
                          x1 = x0 + z, y0 = y1 - z;
                          break;
                      case 3:
                          x0 = x1 - z, y0 = y1 - z;
                          break;
                  }
              }
  
              if (this._root && this._root.length)
                  this._root = node;
          }
  
          this._x0 = x0;
          this._y0 = y0;
          this._x1 = x1;
          this._y1 = y1;
          return this;
      }
  
      function tree_data() {
          var data = [];
          this.visit(function (node) {
              if (!node.length)
                  do
                      data.push(node.data);
                  while (node = node.next)
          });
          return data;
      }
  
      function tree_extent(_) {
          return arguments.length
                  ? this.cover(+_[0][0], +_[0][1]).cover(+_[1][0], +_[1][1])
                  : isNaN(this._x0) ? undefined : [[this._x0, this._y0], [this._x1, this._y1]];
      }
  
      function Quad(node, x0, y0, x1, y1) {
          this.node = node;
          this.x0 = x0;
          this.y0 = y0;
          this.x1 = x1;
          this.y1 = y1;
      }
  
      function tree_find(x, y, radius) {
          var data,
                  x0 = this._x0,
                  y0 = this._y0,
                  x1,
                  y1,
                  x2,
                  y2,
                  x3 = this._x1,
                  y3 = this._y1,
                  quads = [],
                  node = this._root,
                  q,
                  i;
  
          if (node)
              quads.push(new Quad(node, x0, y0, x3, y3));
          if (radius == null)
              radius = Infinity;
          else {
              x0 = x - radius, y0 = y - radius;
              x3 = x + radius, y3 = y + radius;
              radius *= radius;
          }
  
          while (q = quads.pop()) {
  
              // Stop searching if this quadrant can’t contain a closer node.
              if (!(node = q.node)
                      || (x1 = q.x0) > x3
                      || (y1 = q.y0) > y3
                      || (x2 = q.x1) < x0
                      || (y2 = q.y1) < y0)
                  continue;
  
              // Bisect the current quadrant.
              if (node.length) {
                  var xm = (x1 + x2) / 2,
                          ym = (y1 + y2) / 2;
  
                  quads.push(
                          new Quad(node[3], xm, ym, x2, y2),
                          new Quad(node[2], x1, ym, xm, y2),
                          new Quad(node[1], xm, y1, x2, ym),
                          new Quad(node[0], x1, y1, xm, ym)
                          );
  
                  // Visit the closest quadrant first.
                  if (i = (y >= ym) << 1 | (x >= xm)) {
                      q = quads[quads.length - 1];
                      quads[quads.length - 1] = quads[quads.length - 1 - i];
                      quads[quads.length - 1 - i] = q;
                  }
              }
  
              // Visit this point. (Visiting coincident points isn’t necessary!)
              else {
                  var dx = x - +this._x.call(null, node.data),
                          dy = y - +this._y.call(null, node.data),
                          d2 = dx * dx + dy * dy;
                  if (d2 < radius) {
                      var d = Math.sqrt(radius = d2);
                      x0 = x - d, y0 = y - d;
                      x3 = x + d, y3 = y + d;
                      data = node.data;
                  }
              }
          }
  
          return data;
      }
  
      function tree_remove(d) {
          if (isNaN(x = +this._x.call(null, d)) || isNaN(y = +this._y.call(null, d)))
              return this; // ignore invalid points
  
          var parent,
                  node = this._root,
                  retainer,
                  previous,
                  next,
                  x0 = this._x0,
                  y0 = this._y0,
                  x1 = this._x1,
                  y1 = this._y1,
                  x,
                  y,
                  xm,
                  ym,
                  right,
                  bottom,
                  i,
                  j;
  
          // If the tree is empty, initialize the root as a leaf.
          if (!node)
              return this;
  
          // Find the leaf node for the point.
          // While descending, also retain the deepest parent with a non-removed sibling.
          if (node.length)
              while (true) {
                  if (right = x >= (xm = (x0 + x1) / 2))
                      x0 = xm;
                  else
                      x1 = xm;
                  if (bottom = y >= (ym = (y0 + y1) / 2))
                      y0 = ym;
                  else
                      y1 = ym;
                  if (!(parent = node, node = node[i = bottom << 1 | right]))
                      return this;
                  if (!node.length)
                      break;
                  if (parent[(i + 1) & 3] || parent[(i + 2) & 3] || parent[(i + 3) & 3])
                      retainer = parent, j = i;
              }
  
          // Find the point to remove.
          while (node.data !== d)
              if (!(previous = node, node = node.next))
                  return this;
          if (next = node.next)
              delete node.next;
  
          // If there are multiple coincident points, remove just the point.
          if (previous)
              return (next ? previous.next = next : delete previous.next), this;
  
          // If this is the root point, remove it.
          if (!parent)
              return this._root = next, this;
  
          // Remove this leaf.
          next ? parent[i] = next : delete parent[i];
  
          // If the parent now contains exactly one leaf, collapse superfluous parents.
          if ((node = parent[0] || parent[1] || parent[2] || parent[3])
                  && node === (parent[3] || parent[2] || parent[1] || parent[0])
                  && !node.length) {
              if (retainer)
                  retainer[j] = node;
              else
                  this._root = node;
          }
  
          return this;
      }
  
      function removeAll(data) {
          for (var i = 0, n = data.length; i < n; ++i)
              this.remove(data[i]);
          return this;
      }
  
      function tree_root() {
          return this._root;
      }
  
      function tree_size() {
          var size = 0;
          this.visit(function (node) {
              if (!node.length)
                  do
                      ++size;
                  while (node = node.next)
          });
          return size;
      }
  
      function tree_visit(callback) {
          var quads = [], q, node = this._root, child, x0, y0, x1, y1;
          if (node)
              quads.push(new Quad(node, this._x0, this._y0, this._x1, this._y1));
          while (q = quads.pop()) {
              if (!callback(node = q.node, x0 = q.x0, y0 = q.y0, x1 = q.x1, y1 = q.y1) && node.length) {
                  var xm = (x0 + x1) / 2, ym = (y0 + y1) / 2;
                  if (child = node[3])
                      quads.push(new Quad(child, xm, ym, x1, y1));
                  if (child = node[2])
                      quads.push(new Quad(child, x0, ym, xm, y1));
                  if (child = node[1])
                      quads.push(new Quad(child, xm, y0, x1, ym));
                  if (child = node[0])
                      quads.push(new Quad(child, x0, y0, xm, ym));
              }
          }
          return this;
      }
  
      function tree_visitAfter(callback) {
          var quads = [], next = [], q;
          if (this._root)
              quads.push(new Quad(this._root, this._x0, this._y0, this._x1, this._y1));
          while (q = quads.pop()) {
              var node = q.node;
              if (node.length) {
                  var child, x0 = q.x0, y0 = q.y0, x1 = q.x1, y1 = q.y1, xm = (x0 + x1) / 2, ym = (y0 + y1) / 2;
                  if (child = node[0])
                      quads.push(new Quad(child, x0, y0, xm, ym));
                  if (child = node[1])
                      quads.push(new Quad(child, xm, y0, x1, ym));
                  if (child = node[2])
                      quads.push(new Quad(child, x0, ym, xm, y1));
                  if (child = node[3])
                      quads.push(new Quad(child, xm, ym, x1, y1));
              }
              next.push(q);
          }
          while (q = next.pop()) {
              callback(q.node, q.x0, q.y0, q.x1, q.y1);
          }
          return this;
      }
  
      function defaultX$1(d) {
          return d[0];
      }
  
      function tree_x(_) {
          return arguments.length ? (this._x = _, this) : this._x;
      }
  
      function defaultY$1(d) {
          return d[1];
      }
  
      function tree_y(_) {
          return arguments.length ? (this._y = _, this) : this._y;
      }
  
      function quadtree(nodes, x, y) {
          var tree = new Quadtree(x == null ? defaultX$1 : x, y == null ? defaultY$1 : y, NaN, NaN, NaN, NaN);
          return nodes == null ? tree : tree.addAll(nodes);
      }
  
      function Quadtree(x, y, x0, y0, x1, y1) {
          this._x = x;
          this._y = y;
          this._x0 = x0;
          this._y0 = y0;
          this._x1 = x1;
          this._y1 = y1;
          this._root = undefined;
      }
  
      function leaf_copy(leaf) {
          var copy = {data: leaf.data}, next = copy;
          while (leaf = leaf.next)
              next = next.next = {data: leaf.data};
          return copy;
      }
  
      var treeProto = quadtree.prototype = Quadtree.prototype;
  
      treeProto.copy = function () {
          var copy = new Quadtree(this._x, this._y, this._x0, this._y0, this._x1, this._y1),
                  node = this._root,
                  nodes,
                  child;
  
          if (!node)
              return copy;
  
          if (!node.length)
              return copy._root = leaf_copy(node), copy;
  
          nodes = [{source: node, target: copy._root = new Array(4)}];
          while (node = nodes.pop()) {
              for (var i = 0; i < 4; ++i) {
                  if (child = node.source[i]) {
                      if (child.length)
                          nodes.push({source: child, target: node.target[i] = new Array(4)});
                      else
                          node.target[i] = leaf_copy(child);
                  }
              }
          }
  
          return copy;
      };
  
      treeProto.add = tree_add;
      treeProto.addAll = addAll;
      treeProto.cover = tree_cover;
      treeProto.data = tree_data;
      treeProto.extent = tree_extent;
      treeProto.find = tree_find;
      treeProto.remove = tree_remove;
      treeProto.removeAll = removeAll;
      treeProto.root = tree_root;
      treeProto.size = tree_size;
      treeProto.visit = tree_visit;
      treeProto.visitAfter = tree_visitAfter;
      treeProto.x = tree_x;
      treeProto.y = tree_y;
  
      function x(d) {
          return d.x + d.vx;
      }
  
      function y(d) {
          return d.y + d.vy;
      }
  
      function collide(radius) {
          var nodes,
                  radii,
                  strength = 1,
                  iterations = 1;
  
          if (typeof radius !== "function")
              radius = constant$7(radius == null ? 1 : +radius);
  
          function force() {
              var i, n = nodes.length,
                      tree,
                      node,
                      xi,
                      yi,
                      ri,
                      ri2;
  
              for (var k = 0; k < iterations; ++k) {
                  tree = quadtree(nodes, x, y).visitAfter(prepare);
                  for (i = 0; i < n; ++i) {
                      node = nodes[i];
                      ri = radii[node.index], ri2 = ri * ri;
                      xi = node.x + node.vx;
                      yi = node.y + node.vy;
                      tree.visit(apply);
                  }
              }
  
              function apply(quad, x0, y0, x1, y1) {
                  var data = quad.data, rj = quad.r, r = ri + rj;
                  if (data) {
                      if (data.index > node.index) {
                          var x = xi - data.x - data.vx,
                                  y = yi - data.y - data.vy,
                                  l = x * x + y * y;
                          if (l < r * r) {
                              if (x === 0)
                                  x = jiggle(), l += x * x;
                              if (y === 0)
                                  y = jiggle(), l += y * y;
                              l = (r - (l = Math.sqrt(l))) / l * strength;
                              node.vx += (x *= l) * (r = (rj *= rj) / (ri2 + rj));
                              node.vy += (y *= l) * r;
                              data.vx -= x * (r = 1 - r);
                              data.vy -= y * r;
                          }
                      }
                      return;
                  }
                  return x0 > xi + r || x1 < xi - r || y0 > yi + r || y1 < yi - r;
              }
          }
  
          function prepare(quad) {
              if (quad.data)
                  return quad.r = radii[quad.data.index];
              for (var i = quad.r = 0; i < 4; ++i) {
                  if (quad[i] && quad[i].r > quad.r) {
                      quad.r = quad[i].r;
                  }
              }
          }
  
          function initialize() {
              if (!nodes)
                  return;
              var i, n = nodes.length, node;
              radii = new Array(n);
              for (i = 0; i < n; ++i)
                  node = nodes[i], radii[node.index] = +radius(node, i, nodes);
          }
  
          force.initialize = function (_) {
              nodes = _;
              initialize();
          };
  
          force.iterations = function (_) {
              return arguments.length ? (iterations = +_, force) : iterations;
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = +_, force) : strength;
          };
  
          force.radius = function (_) {
              return arguments.length ? (radius = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : radius;
          };
  
          return force;
      }
  
      function index(d) {
          return d.index;
      }
  
      function find(nodeById, nodeId) {
          var node = nodeById.get(nodeId);
          if (!node)
              throw new Error("missing: " + nodeId);
          return node;
      }
  
      function link(links) {
          var id = index,
                  strength = defaultStrength,
                  strengths,
                  distance = constant$7(30),
                  distances,
                  nodes,
                  count,
                  bias,
                  iterations = 1;
  
          if (links == null)
              links = [];
  
          function defaultStrength(link) {
              return 1 / Math.min(count[link.source.index], count[link.target.index]);
          }
  
          function force(alpha) {
              for (var k = 0, n = links.length; k < iterations; ++k) {
                  for (var i = 0, link, source, target, x, y, l, b; i < n; ++i) {
                      link = links[i], source = link.source, target = link.target;
                      x = target.x + target.vx - source.x - source.vx || jiggle();
                      y = target.y + target.vy - source.y - source.vy || jiggle();
                      l = Math.sqrt(x * x + y * y);
                      l = (l - distances[i]) / l * alpha * strengths[i];
                      x *= l, y *= l;
                      target.vx -= x * (b = bias[i]);
                      target.vy -= y * b;
                      source.vx += x * (b = 1 - b);
                      source.vy += y * b;
                  }
              }
          }
  
          function initialize() {
              if (!nodes)
                  return;
  
              var i,
                      n = nodes.length,
                      m = links.length,
                      nodeById = map$1(nodes, id),
                      link;
  
              for (i = 0, count = new Array(n); i < m; ++i) {
                  link = links[i], link.index = i;
                  if (typeof link.source !== "object")
                      link.source = find(nodeById, link.source);
                  if (typeof link.target !== "object")
                      link.target = find(nodeById, link.target);
                  count[link.source.index] = (count[link.source.index] || 0) + 1;
                  count[link.target.index] = (count[link.target.index] || 0) + 1;
              }
  
              for (i = 0, bias = new Array(m); i < m; ++i) {
                  link = links[i], bias[i] = count[link.source.index] / (count[link.source.index] + count[link.target.index]);
              }
  
              strengths = new Array(m), initializeStrength();
              distances = new Array(m), initializeDistance();
          }
  
          function initializeStrength() {
              if (!nodes)
                  return;
  
              for (var i = 0, n = links.length; i < n; ++i) {
                  strengths[i] = +strength(links[i], i, links);
              }
          }
  
          function initializeDistance() {
              if (!nodes)
                  return;
  
              for (var i = 0, n = links.length; i < n; ++i) {
                  distances[i] = +distance(links[i], i, links);
              }
          }
  
          force.initialize = function (_) {
              nodes = _;
              initialize();
          };
  
          force.links = function (_) {
              return arguments.length ? (links = _, initialize(), force) : links;
          };
  
          force.id = function (_) {
              return arguments.length ? (id = _, force) : id;
          };
  
          force.iterations = function (_) {
              return arguments.length ? (iterations = +_, force) : iterations;
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initializeStrength(), force) : strength;
          };
  
          force.distance = function (_) {
              return arguments.length ? (distance = typeof _ === "function" ? _ : constant$7(+_), initializeDistance(), force) : distance;
          };
  
          return force;
      }
  
      function x$1(d) {
          return d.x;
      }
  
      function y$1(d) {
          return d.y;
      }
  
      var initialRadius = 10,
              initialAngle = Math.PI * (3 - Math.sqrt(5));
  
      function simulation(nodes) {
          var simulation,
                  alpha = 1,
                  alphaMin = 0.001,
                  alphaDecay = 1 - Math.pow(alphaMin, 1 / 300),
                  alphaTarget = 0,
                  velocityDecay = 0.6,
                  forces = map$1(),
                  stepper = timer(step),
                  event = dispatch("tick", "end");
  
          if (nodes == null)
              nodes = [];
  
          function step() {
              tick();
              event.call("tick", simulation);
              if (alpha < alphaMin) {
                  stepper.stop();
                  event.call("end", simulation);
              }
          }
  
          function tick(iterations) {
              var i, n = nodes.length, node;
  
              if (iterations === undefined)
                  iterations = 1;
  
              for (var k = 0; k < iterations; ++k) {
                  alpha += (alphaTarget - alpha) * alphaDecay;
  
                  forces.each(function (force) {
                      force(alpha);
                  });
  
                  for (i = 0; i < n; ++i) {
                      node = nodes[i];
                      if (node.fx == null)
                          node.x += node.vx *= velocityDecay;
                      else
                          node.x = node.fx, node.vx = 0;
                      if (node.fy == null)
                          node.y += node.vy *= velocityDecay;
                      else
                          node.y = node.fy, node.vy = 0;
                  }
              }
  
              return simulation;
          }
  
          function initializeNodes() {
              for (var i = 0, n = nodes.length, node; i < n; ++i) {
                  node = nodes[i], node.index = i;
                  if (node.fx != null)
                      node.x = node.fx;
                  if (node.fy != null)
                      node.y = node.fy;
                  if (isNaN(node.x) || isNaN(node.y)) {
                      var radius = initialRadius * Math.sqrt(i), angle = i * initialAngle;
                      node.x = radius * Math.cos(angle);
                      node.y = radius * Math.sin(angle);
                  }
                  if (isNaN(node.vx) || isNaN(node.vy)) {
                      node.vx = node.vy = 0;
                  }
              }
          }
  
          function initializeForce(force) {
              if (force.initialize)
                  force.initialize(nodes);
              return force;
          }
  
          initializeNodes();
  
          return simulation = {
              tick: tick,
  
              restart: function () {
                  return stepper.restart(step), simulation;
              },
  
              stop: function () {
                  return stepper.stop(), simulation;
              },
  
              nodes: function (_) {
                  return arguments.length ? (nodes = _, initializeNodes(), forces.each(initializeForce), simulation) : nodes;
              },
  
              alpha: function (_) {
                  return arguments.length ? (alpha = +_, simulation) : alpha;
              },
  
              alphaMin: function (_) {
                  return arguments.length ? (alphaMin = +_, simulation) : alphaMin;
              },
  
              alphaDecay: function (_) {
                  return arguments.length ? (alphaDecay = +_, simulation) : +alphaDecay;
              },
  
              alphaTarget: function (_) {
                  return arguments.length ? (alphaTarget = +_, simulation) : alphaTarget;
              },
  
              velocityDecay: function (_) {
                  return arguments.length ? (velocityDecay = 1 - _, simulation) : 1 - velocityDecay;
              },
  
              force: function (name, _) {
                  return arguments.length > 1 ? ((_ == null ? forces.remove(name) : forces.set(name, initializeForce(_))), simulation) : forces.get(name);
              },
  
              find: function (x, y, radius) {
                  var i = 0,
                          n = nodes.length,
                          dx,
                          dy,
                          d2,
                          node,
                          closest;
  
                  if (radius == null)
                      radius = Infinity;
                  else
                      radius *= radius;
  
                  for (i = 0; i < n; ++i) {
                      node = nodes[i];
                      dx = x - node.x;
                      dy = y - node.y;
                      d2 = dx * dx + dy * dy;
                      if (d2 < radius)
                          closest = node, radius = d2;
                  }
  
                  return closest;
              },
  
              on: function (name, _) {
                  return arguments.length > 1 ? (event.on(name, _), simulation) : event.on(name);
              }
          };
      }
  
      function manyBody() {
          var nodes,
                  node,
                  alpha,
                  strength = constant$7(-30),
                  strengths,
                  distanceMin2 = 1,
                  distanceMax2 = Infinity,
                  theta2 = 0.81;
  
          function force(_) {
              var i, n = nodes.length, tree = quadtree(nodes, x$1, y$1).visitAfter(accumulate);
              for (alpha = _, i = 0; i < n; ++i)
                  node = nodes[i], tree.visit(apply);
          }
  
          function initialize() {
              if (!nodes)
                  return;
              var i, n = nodes.length, node;
              strengths = new Array(n);
              for (i = 0; i < n; ++i)
                  node = nodes[i], strengths[node.index] = +strength(node, i, nodes);
          }
  
          function accumulate(quad) {
              var strength = 0, q, c, weight = 0, x, y, i;
  
              // For internal nodes, accumulate forces from child quadrants.
              if (quad.length) {
                  for (x = y = i = 0; i < 4; ++i) {
                      if ((q = quad[i]) && (c = Math.abs(q.value))) {
                          strength += q.value, weight += c, x += c * q.x, y += c * q.y;
                      }
                  }
                  quad.x = x / weight;
                  quad.y = y / weight;
              }
  
              // For leaf nodes, accumulate forces from coincident quadrants.
              else {
                  q = quad;
                  q.x = q.data.x;
                  q.y = q.data.y;
                  do
                      strength += strengths[q.data.index];
                  while (q = q.next);
              }
  
              quad.value = strength;
          }
  
          function apply(quad, x1, _, x2) {
              if (!quad.value)
                  return true;
  
              var x = quad.x - node.x,
                      y = quad.y - node.y,
                      w = x2 - x1,
                      l = x * x + y * y;
  
              // Apply the Barnes-Hut approximation if possible.
              // Limit forces for very close nodes; randomize direction if coincident.
              if (w * w / theta2 < l) {
                  if (l < distanceMax2) {
                      if (x === 0)
                          x = jiggle(), l += x * x;
                      if (y === 0)
                          y = jiggle(), l += y * y;
                      if (l < distanceMin2)
                          l = Math.sqrt(distanceMin2 * l);
                      node.vx += x * quad.value * alpha / l;
                      node.vy += y * quad.value * alpha / l;
                  }
                  return true;
              }
  
              // Otherwise, process points directly.
              else if (quad.length || l >= distanceMax2)
                  return;
  
              // Limit forces for very close nodes; randomize direction if coincident.
              if (quad.data !== node || quad.next) {
                  if (x === 0)
                      x = jiggle(), l += x * x;
                  if (y === 0)
                      y = jiggle(), l += y * y;
                  if (l < distanceMin2)
                      l = Math.sqrt(distanceMin2 * l);
              }
  
              do
                  if (quad.data !== node) {
                      w = strengths[quad.data.index] * alpha / l;
                      node.vx += x * w;
                      node.vy += y * w;
                  }
              while (quad = quad.next);
          }
  
          force.initialize = function (_) {
              nodes = _;
              initialize();
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
          };
  
          force.distanceMin = function (_) {
              return arguments.length ? (distanceMin2 = _ * _, force) : Math.sqrt(distanceMin2);
          };
  
          force.distanceMax = function (_) {
              return arguments.length ? (distanceMax2 = _ * _, force) : Math.sqrt(distanceMax2);
          };
  
          force.theta = function (_) {
              return arguments.length ? (theta2 = _ * _, force) : Math.sqrt(theta2);
          };
  
          return force;
      }
  
      function radial(radius, x, y) {
          var nodes,
                  strength = constant$7(0.1),
                  strengths,
                  radiuses;
  
          if (typeof radius !== "function")
              radius = constant$7(+radius);
          if (x == null)
              x = 0;
          if (y == null)
              y = 0;
  
          function force(alpha) {
              for (var i = 0, n = nodes.length; i < n; ++i) {
                  var node = nodes[i],
                          dx = node.x - x || 1e-6,
                          dy = node.y - y || 1e-6,
                          r = Math.sqrt(dx * dx + dy * dy),
                          k = (radiuses[i] - r) * strengths[i] * alpha / r;
                  node.vx += dx * k;
                  node.vy += dy * k;
              }
          }
  
          function initialize() {
              if (!nodes)
                  return;
              var i, n = nodes.length;
              strengths = new Array(n);
              radiuses = new Array(n);
              for (i = 0; i < n; ++i) {
                  radiuses[i] = +radius(nodes[i], i, nodes);
                  strengths[i] = isNaN(radiuses[i]) ? 0 : +strength(nodes[i], i, nodes);
              }
          }
  
          force.initialize = function (_) {
              nodes = _, initialize();
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
          };
  
          force.radius = function (_) {
              return arguments.length ? (radius = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : radius;
          };
  
          force.x = function (_) {
              return arguments.length ? (x = +_, force) : x;
          };
  
          force.y = function (_) {
              return arguments.length ? (y = +_, force) : y;
          };
  
          return force;
      }
  
      function x$2(x) {
          var strength = constant$7(0.1),
                  nodes,
                  strengths,
                  xz;
  
          if (typeof x !== "function")
              x = constant$7(x == null ? 0 : +x);
  
          function force(alpha) {
              for (var i = 0, n = nodes.length, node; i < n; ++i) {
                  node = nodes[i], node.vx += (xz[i] - node.x) * strengths[i] * alpha;
              }
          }
  
          function initialize() {
              if (!nodes)
                  return;
              var i, n = nodes.length;
              strengths = new Array(n);
              xz = new Array(n);
              for (i = 0; i < n; ++i) {
                  strengths[i] = isNaN(xz[i] = +x(nodes[i], i, nodes)) ? 0 : +strength(nodes[i], i, nodes);
              }
          }
  
          force.initialize = function (_) {
              nodes = _;
              initialize();
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
          };
  
          force.x = function (_) {
              return arguments.length ? (x = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : x;
          };
  
          return force;
      }
  
      function y$2(y) {
          var strength = constant$7(0.1),
                  nodes,
                  strengths,
                  yz;
  
          if (typeof y !== "function")
              y = constant$7(y == null ? 0 : +y);
  
          function force(alpha) {
              for (var i = 0, n = nodes.length, node; i < n; ++i) {
                  node = nodes[i], node.vy += (yz[i] - node.y) * strengths[i] * alpha;
              }
          }
  
          function initialize() {
              if (!nodes)
                  return;
              var i, n = nodes.length;
              strengths = new Array(n);
              yz = new Array(n);
              for (i = 0; i < n; ++i) {
                  strengths[i] = isNaN(yz[i] = +y(nodes[i], i, nodes)) ? 0 : +strength(nodes[i], i, nodes);
              }
          }
  
          force.initialize = function (_) {
              nodes = _;
              initialize();
          };
  
          force.strength = function (_) {
              return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
          };
  
          force.y = function (_) {
              return arguments.length ? (y = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : y;
          };
  
          return force;
      }
  
  // Computes the decimal coefficient and exponent of the specified number x with
  // significant digits p, where x is positive and p is in [1, 21] or undefined.
  // For example, formatDecimal(1.23) returns ["123", 0].
      function formatDecimal(x, p) {
          if ((i = (x = p ? x.toExponential(p - 1) : x.toExponential()).indexOf("e")) < 0)
              return null; // NaN, ±Infinity
          var i, coefficient = x.slice(0, i);
  
          // The string returned by toExponential either has the form \d\.\d+e[-+]\d+
          // (e.g., 1.2e+3) or the form \de[-+]\d+ (e.g., 1e+3).
          return [
              coefficient.length > 1 ? coefficient[0] + coefficient.slice(2) : coefficient,
              +x.slice(i + 1)
          ];
      }
  
      function exponent$1(x) {
          return x = formatDecimal(Math.abs(x)), x ? x[1] : NaN;
      }
  
      function formatGroup(grouping, thousands) {
          return function (value, width) {
              var i = value.length,
                      t = [],
                      j = 0,
                      g = grouping[0],
                      length = 0;
  
              while (i > 0 && g > 0) {
                  if (length + g + 1 > width)
                      g = Math.max(1, width - length);
                  t.push(value.substring(i -= g, i + g));
                  if ((length += g + 1) > width)
                      break;
                  g = grouping[j = (j + 1) % grouping.length];
              }
  
              return t.reverse().join(thousands);
          };
      }
  
      function formatNumerals(numerals) {
          return function (value) {
              return value.replace(/[0-9]/g, function (i) {
                  return numerals[+i];
              });
          };
      }
  
  // [[fill]align][sign][symbol][0][width][,][.precision][~][type]
      var re = /^(?:(.)?([<>=^]))?([+\-( ])?([$#])?(0)?(\d+)?(,)?(\.\d+)?(~)?([a-z%])?$/i;
  
      function formatSpecifier(specifier) {
          if (!(match = re.exec(specifier)))
              throw new Error("invalid format: " + specifier);
          var match;
          return new FormatSpecifier({
              fill: match[1],
              align: match[2],
              sign: match[3],
              symbol: match[4],
              zero: match[5],
              width: match[6],
              comma: match[7],
              precision: match[8] && match[8].slice(1),
              trim: match[9],
              type: match[10]
          });
      }
  
      formatSpecifier.prototype = FormatSpecifier.prototype; // instanceof
  
      function FormatSpecifier(specifier) {
          this.fill = specifier.fill === undefined ? " " : specifier.fill + "";
          this.align = specifier.align === undefined ? ">" : specifier.align + "";
          this.sign = specifier.sign === undefined ? "-" : specifier.sign + "";
          this.symbol = specifier.symbol === undefined ? "" : specifier.symbol + "";
          this.zero = !!specifier.zero;
          this.width = specifier.width === undefined ? undefined : +specifier.width;
          this.comma = !!specifier.comma;
          this.precision = specifier.precision === undefined ? undefined : +specifier.precision;
          this.trim = !!specifier.trim;
          this.type = specifier.type === undefined ? "" : specifier.type + "";
      }
  
      FormatSpecifier.prototype.toString = function () {
          return this.fill
                  + this.align
                  + this.sign
                  + this.symbol
                  + (this.zero ? "0" : "")
                  + (this.width === undefined ? "" : Math.max(1, this.width | 0))
                  + (this.comma ? "," : "")
                  + (this.precision === undefined ? "" : "." + Math.max(0, this.precision | 0))
                  + (this.trim ? "~" : "")
                  + this.type;
      };
  
  // Trims insignificant zeros, e.g., replaces 1.2000k with 1.2k.
      function formatTrim(s) {
          out: for (var n = s.length, i = 1, i0 = -1, i1; i < n; ++i) {
              switch (s[i]) {
                  case ".":
                      i0 = i1 = i;
                      break;
                  case "0":
                      if (i0 === 0)
                          i0 = i;
                      i1 = i;
                      break;
                  default:
                      if (!+s[i])
                          break out;
                      if (i0 > 0)
                          i0 = 0;
                      break;
              }
          }
          return i0 > 0 ? s.slice(0, i0) + s.slice(i1 + 1) : s;
      }
  
      var prefixExponent;
  
      function formatPrefixAuto(x, p) {
          var d = formatDecimal(x, p);
          if (!d)
              return x + "";
          var coefficient = d[0],
                  exponent = d[1],
                  i = exponent - (prefixExponent = Math.max(-8, Math.min(8, Math.floor(exponent / 3))) * 3) + 1,
                  n = coefficient.length;
          return i === n ? coefficient
                  : i > n ? coefficient + new Array(i - n + 1).join("0")
                  : i > 0 ? coefficient.slice(0, i) + "." + coefficient.slice(i)
                  : "0." + new Array(1 - i).join("0") + formatDecimal(x, Math.max(0, p + i - 1))[0]; // less than 1y!
      }
  
      function formatRounded(x, p) {
          var d = formatDecimal(x, p);
          if (!d)
              return x + "";
          var coefficient = d[0],
                  exponent = d[1];
          return exponent < 0 ? "0." + new Array(-exponent).join("0") + coefficient
                  : coefficient.length > exponent + 1 ? coefficient.slice(0, exponent + 1) + "." + coefficient.slice(exponent + 1)
                  : coefficient + new Array(exponent - coefficient.length + 2).join("0");
      }
  
      var formatTypes = {
          "%": function (x, p) {
              return (x * 100).toFixed(p);
          },
          "b": function (x) {
              return Math.round(x).toString(2);
          },
          "c": function (x) {
              return x + "";
          },
          "d": function (x) {
              return Math.round(x).toString(10);
          },
          "e": function (x, p) {
              return x.toExponential(p);
          },
          "f": function (x, p) {
              return x.toFixed(p);
          },
          "g": function (x, p) {
              return x.toPrecision(p);
          },
          "o": function (x) {
              return Math.round(x).toString(8);
          },
          "p": function (x, p) {
              return formatRounded(x * 100, p);
          },
          "r": formatRounded,
          "s": formatPrefixAuto,
          "X": function (x) {
              return Math.round(x).toString(16).toUpperCase();
          },
          "x": function (x) {
              return Math.round(x).toString(16);
          }
      };
  
      function identity$3(x) {
          return x;
      }
  
      var map$2 = Array.prototype.map,
              prefixes = ["y", "z", "a", "f", "p", "n", "\xB5", "m", "", "k", "M", "G", "T", "P", "E", "Z", "Y"];
  
      function formatLocale(locale) {
          var group = locale.grouping === undefined || locale.thousands === undefined ? identity$3 : formatGroup(map$2.call(locale.grouping, Number), locale.thousands + ""),
                  currencyPrefix = locale.currency === undefined ? "" : locale.currency[0] + "",
                  currencySuffix = locale.currency === undefined ? "" : locale.currency[1] + "",
                  decimal = locale.decimal === undefined ? "." : locale.decimal + "",
                  numerals = locale.numerals === undefined ? identity$3 : formatNumerals(map$2.call(locale.numerals, String)),
                  percent = locale.percent === undefined ? "%" : locale.percent + "",
                  minus = locale.minus === undefined ? "-" : locale.minus + "",
                  nan = locale.nan === undefined ? "NaN" : locale.nan + "";
  
          function newFormat(specifier) {
              specifier = formatSpecifier(specifier);
  
              var fill = specifier.fill,
                      align = specifier.align,
                      sign = specifier.sign,
                      symbol = specifier.symbol,
                      zero = specifier.zero,
                      width = specifier.width,
                      comma = specifier.comma,
                      precision = specifier.precision,
                      trim = specifier.trim,
                      type = specifier.type;
  
              // The "n" type is an alias for ",g".
              if (type === "n")
                  comma = true, type = "g";
  
              // The "" type, and any invalid type, is an alias for ".12~g".
              else if (!formatTypes[type])
                  precision === undefined && (precision = 12), trim = true, type = "g";
  
              // If zero fill is specified, padding goes after sign and before digits.
              if (zero || (fill === "0" && align === "="))
                  zero = true, fill = "0", align = "=";
  
              // Compute the prefix and suffix.
              // For SI-prefix, the suffix is lazily computed.
              var prefix = symbol === "$" ? currencyPrefix : symbol === "#" && /[boxX]/.test(type) ? "0" + type.toLowerCase() : "",
                      suffix = symbol === "$" ? currencySuffix : /[%p]/.test(type) ? percent : "";
  
              // What format function should we use?
              // Is this an integer type?
              // Can this type generate exponential notation?
              var formatType = formatTypes[type],
                      maybeSuffix = /[defgprs%]/.test(type);
  
              // Set the default precision if not specified,
              // or clamp the specified precision to the supported range.
              // For significant precision, it must be in [1, 21].
              // For fixed precision, it must be in [0, 20].
              precision = precision === undefined ? 6
                      : /[gprs]/.test(type) ? Math.max(1, Math.min(21, precision))
                      : Math.max(0, Math.min(20, precision));
  
              function format(value) {
                  var valuePrefix = prefix,
                          valueSuffix = suffix,
                          i, n, c;
  
                  if (type === "c") {
                      valueSuffix = formatType(value) + valueSuffix;
                      value = "";
                  } else {
                      value = +value;
  
                      // Determine the sign. -0 is not less than 0, but 1 / -0 is!
                      var valueNegative = value < 0 || 1 / value < 0;
  
                      // Perform the initial formatting.
                      value = isNaN(value) ? nan : formatType(Math.abs(value), precision);
  
                      // Trim insignificant zeros.
                      if (trim)
                          value = formatTrim(value);
  
                      // If a negative value rounds to zero after formatting, and no explicit positive sign is requested, hide the sign.
                      if (valueNegative && +value === 0 && sign !== "+")
                          valueNegative = false;
  
                      // Compute the prefix and suffix.
                      valuePrefix = (valueNegative ? (sign === "(" ? sign : minus) : sign === "-" || sign === "(" ? "" : sign) + valuePrefix;
                      valueSuffix = (type === "s" ? prefixes[8 + prefixExponent / 3] : "") + valueSuffix + (valueNegative && sign === "(" ? ")" : "");
  
                      // Break the formatted value into the integer “value” part that can be
                      // grouped, and fractional or exponential “suffix” part that is not.
                      if (maybeSuffix) {
                          i = -1, n = value.length;
                          while (++i < n) {
                              if (c = value.charCodeAt(i), 48 > c || c > 57) {
                                  valueSuffix = (c === 46 ? decimal + value.slice(i + 1) : value.slice(i)) + valueSuffix;
                                  value = value.slice(0, i);
                                  break;
                              }
                          }
                      }
                  }
  
                  // If the fill character is not "0", grouping is applied before padding.
                  if (comma && !zero)
                      value = group(value, Infinity);
  
                  // Compute the padding.
                  var length = valuePrefix.length + value.length + valueSuffix.length,
                          padding = length < width ? new Array(width - length + 1).join(fill) : "";
  
                  // If the fill character is "0", grouping is applied after padding.
                  if (comma && zero)
                      value = group(padding + value, padding.length ? width - valueSuffix.length : Infinity), padding = "";
  
                  // Reconstruct the final output based on the desired alignment.
                  switch (align) {
                      case "<":
                          value = valuePrefix + value + valueSuffix + padding;
                          break;
                      case "=":
                          value = valuePrefix + padding + value + valueSuffix;
                          break;
                      case "^":
                          value = padding.slice(0, length = padding.length >> 1) + valuePrefix + value + valueSuffix + padding.slice(length);
                          break;
                      default:
                          value = padding + valuePrefix + value + valueSuffix;
                          break;
                  }
  
                  return numerals(value);
              }
  
              format.toString = function () {
                  return specifier + "";
              };
  
              return format;
          }
  
          function formatPrefix(specifier, value) {
              var f = newFormat((specifier = formatSpecifier(specifier), specifier.type = "f", specifier)),
                      e = Math.max(-8, Math.min(8, Math.floor(exponent$1(value) / 3))) * 3,
                      k = Math.pow(10, -e),
                      prefix = prefixes[8 + e / 3];
              return function (value) {
                  return f(k * value) + prefix;
              };
          }
  
          return {
              format: newFormat,
              formatPrefix: formatPrefix
          };
      }
  
      var locale;
  
      defaultLocale({
          decimal: ".",
          thousands: ",",
          grouping: [3],
          currency: ["$", ""],
          minus: "-"
      });
  
      function defaultLocale(definition) {
          locale = formatLocale(definition);
          exports.format = locale.format;
          exports.formatPrefix = locale.formatPrefix;
          return locale;
      }
  
      function precisionFixed(step) {
          return Math.max(0, -exponent$1(Math.abs(step)));
      }
  
      function precisionPrefix(step, value) {
          return Math.max(0, Math.max(-8, Math.min(8, Math.floor(exponent$1(value) / 3))) * 3 - exponent$1(Math.abs(step)));
      }
  
      function precisionRound(step, max) {
          step = Math.abs(step), max = Math.abs(max) - step;
          return Math.max(0, exponent$1(max) - exponent$1(step)) + 1;
      }
  
  // Adds floating point numbers with twice the normal precision.
  // Reference: J. R. Shewchuk, Adaptive Precision Floating-Point Arithmetic and
  // Fast Robust Geometric Predicates, Discrete & Computational Geometry 18(3)
  // 305–363 (1997).
  // Code adapted from GeographicLib by Charles F. F. Karney,
  // http://geographiclib.sourceforge.net/
  
      function adder() {
          return new Adder;
      }
  
      function Adder() {
          this.reset();
      }
  
      Adder.prototype = {
          constructor: Adder,
          reset: function () {
              this.s = // rounded value
                      this.t = 0; // exact error
          },
          add: function (y) {
              add$1(temp, y, this.t);
              add$1(this, temp.s, this.s);
              if (this.s)
                  this.t += temp.t;
              else
                  this.s = temp.t;
          },
          valueOf: function () {
              return this.s;
          }
      };
  
      var temp = new Adder;
  
      function add$1(adder, a, b) {
          var x = adder.s = a + b,
                  bv = x - a,
                  av = x - bv;
          adder.t = (a - av) + (b - bv);
      }
  
      var epsilon$2 = 1e-6;
      var epsilon2$1 = 1e-12;
      var pi$3 = Math.PI;
      var halfPi$2 = pi$3 / 2;
      var quarterPi = pi$3 / 4;
      var tau$3 = pi$3 * 2;
  
      var degrees$1 = 180 / pi$3;
      var radians = pi$3 / 180;
  
      var abs = Math.abs;
      var atan = Math.atan;
      var atan2 = Math.atan2;
      var cos$1 = Math.cos;
      var ceil = Math.ceil;
      var exp = Math.exp;
      var log = Math.log;
      var pow = Math.pow;
      var sin$1 = Math.sin;
      var sign = Math.sign || function (x) {
          return x > 0 ? 1 : x < 0 ? -1 : 0;
      };
      var sqrt = Math.sqrt;
      var tan = Math.tan;
  
      function acos(x) {
          return x > 1 ? 0 : x < -1 ? pi$3 : Math.acos(x);
      }
  
      function asin(x) {
          return x > 1 ? halfPi$2 : x < -1 ? -halfPi$2 : Math.asin(x);
      }
  
      function haversin(x) {
          return (x = sin$1(x / 2)) * x;
      }
  
      function noop$2() {}
  
      function streamGeometry(geometry, stream) {
          if (geometry && streamGeometryType.hasOwnProperty(geometry.type)) {
              streamGeometryType[geometry.type](geometry, stream);
          }
      }
  
      var streamObjectType = {
          Feature: function (object, stream) {
              streamGeometry(object.geometry, stream);
          },
          FeatureCollection: function (object, stream) {
              var features = object.features, i = -1, n = features.length;
              while (++i < n)
                  streamGeometry(features[i].geometry, stream);
          }
      };
  
      var streamGeometryType = {
          Sphere: function (object, stream) {
              stream.sphere();
          },
          Point: function (object, stream) {
              object = object.coordinates;
              stream.point(object[0], object[1], object[2]);
          },
          MultiPoint: function (object, stream) {
              var coordinates = object.coordinates, i = -1, n = coordinates.length;
              while (++i < n)
                  object = coordinates[i], stream.point(object[0], object[1], object[2]);
          },
          LineString: function (object, stream) {
              streamLine(object.coordinates, stream, 0);
          },
          MultiLineString: function (object, stream) {
              var coordinates = object.coordinates, i = -1, n = coordinates.length;
              while (++i < n)
                  streamLine(coordinates[i], stream, 0);
          },
          Polygon: function (object, stream) {
              streamPolygon(object.coordinates, stream);
          },
          MultiPolygon: function (object, stream) {
              var coordinates = object.coordinates, i = -1, n = coordinates.length;
              while (++i < n)
                  streamPolygon(coordinates[i], stream);
          },
          GeometryCollection: function (object, stream) {
              var geometries = object.geometries, i = -1, n = geometries.length;
              while (++i < n)
                  streamGeometry(geometries[i], stream);
          }
      };
  
      function streamLine(coordinates, stream, closed) {
          var i = -1, n = coordinates.length - closed, coordinate;
          stream.lineStart();
          while (++i < n)
              coordinate = coordinates[i], stream.point(coordinate[0], coordinate[1], coordinate[2]);
          stream.lineEnd();
      }
  
      function streamPolygon(coordinates, stream) {
          var i = -1, n = coordinates.length;
          stream.polygonStart();
          while (++i < n)
              streamLine(coordinates[i], stream, 1);
          stream.polygonEnd();
      }
  
      function geoStream(object, stream) {
          if (object && streamObjectType.hasOwnProperty(object.type)) {
              streamObjectType[object.type](object, stream);
          } else {
              streamGeometry(object, stream);
          }
      }
  
      var areaRingSum = adder();
  
      var areaSum = adder(),
              lambda00,
              phi00,
              lambda0,
              cosPhi0,
              sinPhi0;
  
      var areaStream = {
          point: noop$2,
          lineStart: noop$2,
          lineEnd: noop$2,
          polygonStart: function () {
              areaRingSum.reset();
              areaStream.lineStart = areaRingStart;
              areaStream.lineEnd = areaRingEnd;
          },
          polygonEnd: function () {
              var areaRing = +areaRingSum;
              areaSum.add(areaRing < 0 ? tau$3 + areaRing : areaRing);
              this.lineStart = this.lineEnd = this.point = noop$2;
          },
          sphere: function () {
              areaSum.add(tau$3);
          }
      };
  
      function areaRingStart() {
          areaStream.point = areaPointFirst;
      }
  
      function areaRingEnd() {
          areaPoint(lambda00, phi00);
      }
  
      function areaPointFirst(lambda, phi) {
          areaStream.point = areaPoint;
          lambda00 = lambda, phi00 = phi;
          lambda *= radians, phi *= radians;
          lambda0 = lambda, cosPhi0 = cos$1(phi = phi / 2 + quarterPi), sinPhi0 = sin$1(phi);
      }
  
      function areaPoint(lambda, phi) {
          lambda *= radians, phi *= radians;
          phi = phi / 2 + quarterPi; // half the angular distance from south pole
  
          // Spherical excess E for a spherical triangle with vertices: south pole,
          // previous point, current point.  Uses a formula derived from Cagnoli’s
          // theorem.  See Todhunter, Spherical Trig. (1871), Sec. 103, Eq. (2).
          var dLambda = lambda - lambda0,
                  sdLambda = dLambda >= 0 ? 1 : -1,
                  adLambda = sdLambda * dLambda,
                  cosPhi = cos$1(phi),
                  sinPhi = sin$1(phi),
                  k = sinPhi0 * sinPhi,
                  u = cosPhi0 * cosPhi + k * cos$1(adLambda),
                  v = k * sdLambda * sin$1(adLambda);
          areaRingSum.add(atan2(v, u));
  
          // Advance the previous points.
          lambda0 = lambda, cosPhi0 = cosPhi, sinPhi0 = sinPhi;
      }
  
      function area$1(object) {
          areaSum.reset();
          geoStream(object, areaStream);
          return areaSum * 2;
      }
  
      function spherical(cartesian) {
          return [atan2(cartesian[1], cartesian[0]), asin(cartesian[2])];
      }
  
      function cartesian(spherical) {
          var lambda = spherical[0], phi = spherical[1], cosPhi = cos$1(phi);
          return [cosPhi * cos$1(lambda), cosPhi * sin$1(lambda), sin$1(phi)];
      }
  
      function cartesianDot(a, b) {
          return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
      }
  
      function cartesianCross(a, b) {
          return [a[1] * b[2] - a[2] * b[1], a[2] * b[0] - a[0] * b[2], a[0] * b[1] - a[1] * b[0]];
      }
  
  // TODO return a
      function cartesianAddInPlace(a, b) {
          a[0] += b[0], a[1] += b[1], a[2] += b[2];
      }
  
      function cartesianScale(vector, k) {
          return [vector[0] * k, vector[1] * k, vector[2] * k];
      }
  
  // TODO return d
      function cartesianNormalizeInPlace(d) {
          var l = sqrt(d[0] * d[0] + d[1] * d[1] + d[2] * d[2]);
          d[0] /= l, d[1] /= l, d[2] /= l;
      }
  
      var lambda0$1, phi0, lambda1, phi1, // bounds
              lambda2, // previous lambda-coordinate
              lambda00$1, phi00$1, // first point
              p0, // previous 3D point
              deltaSum = adder(),
              ranges,
              range;
  
      var boundsStream = {
          point: boundsPoint,
          lineStart: boundsLineStart,
          lineEnd: boundsLineEnd,
          polygonStart: function () {
              boundsStream.point = boundsRingPoint;
              boundsStream.lineStart = boundsRingStart;
              boundsStream.lineEnd = boundsRingEnd;
              deltaSum.reset();
              areaStream.polygonStart();
          },
          polygonEnd: function () {
              areaStream.polygonEnd();
              boundsStream.point = boundsPoint;
              boundsStream.lineStart = boundsLineStart;
              boundsStream.lineEnd = boundsLineEnd;
              if (areaRingSum < 0)
                  lambda0$1 = -(lambda1 = 180), phi0 = -(phi1 = 90);
              else if (deltaSum > epsilon$2)
                  phi1 = 90;
              else if (deltaSum < -epsilon$2)
                  phi0 = -90;
              range[0] = lambda0$1, range[1] = lambda1;
          },
          sphere: function () {
              lambda0$1 = -(lambda1 = 180), phi0 = -(phi1 = 90);
          }
      };
  
      function boundsPoint(lambda, phi) {
          ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]);
          if (phi < phi0)
              phi0 = phi;
          if (phi > phi1)
              phi1 = phi;
      }
  
      function linePoint(lambda, phi) {
          var p = cartesian([lambda * radians, phi * radians]);
          if (p0) {
              var normal = cartesianCross(p0, p),
                      equatorial = [normal[1], -normal[0], 0],
                      inflection = cartesianCross(equatorial, normal);
              cartesianNormalizeInPlace(inflection);
              inflection = spherical(inflection);
              var delta = lambda - lambda2,
                      sign = delta > 0 ? 1 : -1,
                      lambdai = inflection[0] * degrees$1 * sign,
                      phii,
                      antimeridian = abs(delta) > 180;
              if (antimeridian ^ (sign * lambda2 < lambdai && lambdai < sign * lambda)) {
                  phii = inflection[1] * degrees$1;
                  if (phii > phi1)
                      phi1 = phii;
              } else if (lambdai = (lambdai + 360) % 360 - 180, antimeridian ^ (sign * lambda2 < lambdai && lambdai < sign * lambda)) {
                  phii = -inflection[1] * degrees$1;
                  if (phii < phi0)
                      phi0 = phii;
              } else {
                  if (phi < phi0)
                      phi0 = phi;
                  if (phi > phi1)
                      phi1 = phi;
              }
              if (antimeridian) {
                  if (lambda < lambda2) {
                      if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1))
                          lambda1 = lambda;
                  } else {
                      if (angle(lambda, lambda1) > angle(lambda0$1, lambda1))
                          lambda0$1 = lambda;
                  }
              } else {
                  if (lambda1 >= lambda0$1) {
                      if (lambda < lambda0$1)
                          lambda0$1 = lambda;
                      if (lambda > lambda1)
                          lambda1 = lambda;
                  } else {
                      if (lambda > lambda2) {
                          if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1))
                              lambda1 = lambda;
                      } else {
                          if (angle(lambda, lambda1) > angle(lambda0$1, lambda1))
                              lambda0$1 = lambda;
                      }
                  }
              }
          } else {
              ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]);
          }
          if (phi < phi0)
              phi0 = phi;
          if (phi > phi1)
              phi1 = phi;
          p0 = p, lambda2 = lambda;
      }
  
      function boundsLineStart() {
          boundsStream.point = linePoint;
      }
  
      function boundsLineEnd() {
          range[0] = lambda0$1, range[1] = lambda1;
          boundsStream.point = boundsPoint;
          p0 = null;
      }
  
      function boundsRingPoint(lambda, phi) {
          if (p0) {
              var delta = lambda - lambda2;
              deltaSum.add(abs(delta) > 180 ? delta + (delta > 0 ? 360 : -360) : delta);
          } else {
              lambda00$1 = lambda, phi00$1 = phi;
          }
          areaStream.point(lambda, phi);
          linePoint(lambda, phi);
      }
  
      function boundsRingStart() {
          areaStream.lineStart();
      }
  
      function boundsRingEnd() {
          boundsRingPoint(lambda00$1, phi00$1);
          areaStream.lineEnd();
          if (abs(deltaSum) > epsilon$2)
              lambda0$1 = -(lambda1 = 180);
          range[0] = lambda0$1, range[1] = lambda1;
          p0 = null;
      }
  
  // Finds the left-right distance between two longitudes.
  // This is almost the same as (lambda1 - lambda0 + 360°) % 360°, except that we want
  // the distance between ±180° to be 360°.
      function angle(lambda0, lambda1) {
          return (lambda1 -= lambda0) < 0 ? lambda1 + 360 : lambda1;
      }
  
      function rangeCompare(a, b) {
          return a[0] - b[0];
      }
  
      function rangeContains(range, x) {
          return range[0] <= range[1] ? range[0] <= x && x <= range[1] : x < range[0] || range[1] < x;
      }
  
      function bounds(feature) {
          var i, n, a, b, merged, deltaMax, delta;
  
          phi1 = lambda1 = -(lambda0$1 = phi0 = Infinity);
          ranges = [];
          geoStream(feature, boundsStream);
  
          // First, sort ranges by their minimum longitudes.
          if (n = ranges.length) {
              ranges.sort(rangeCompare);
  
              // Then, merge any ranges that overlap.
              for (i = 1, a = ranges[0], merged = [a]; i < n; ++i) {
                  b = ranges[i];
                  if (rangeContains(a, b[0]) || rangeContains(a, b[1])) {
                      if (angle(a[0], b[1]) > angle(a[0], a[1]))
                          a[1] = b[1];
                      if (angle(b[0], a[1]) > angle(a[0], a[1]))
                          a[0] = b[0];
                  } else {
                      merged.push(a = b);
                  }
              }
  
              // Finally, find the largest gap between the merged ranges.
              // The final bounding box will be the inverse of this gap.
              for (deltaMax = -Infinity, n = merged.length - 1, i = 0, a = merged[n]; i <= n; a = b, ++i) {
                  b = merged[i];
                  if ((delta = angle(a[1], b[0])) > deltaMax)
                      deltaMax = delta, lambda0$1 = b[0], lambda1 = a[1];
              }
          }
  
          ranges = range = null;
  
          return lambda0$1 === Infinity || phi0 === Infinity
                  ? [[NaN, NaN], [NaN, NaN]]
                  : [[lambda0$1, phi0], [lambda1, phi1]];
      }
  
      var W0, W1,
              X0, Y0, Z0,
              X1, Y1, Z1,
              X2, Y2, Z2,
              lambda00$2, phi00$2, // first point
              x0, y0, z0; // previous point
  
      var centroidStream = {
          sphere: noop$2,
          point: centroidPoint,
          lineStart: centroidLineStart,
          lineEnd: centroidLineEnd,
          polygonStart: function () {
              centroidStream.lineStart = centroidRingStart;
              centroidStream.lineEnd = centroidRingEnd;
          },
          polygonEnd: function () {
              centroidStream.lineStart = centroidLineStart;
              centroidStream.lineEnd = centroidLineEnd;
          }
      };
  
  // Arithmetic mean of Cartesian vectors.
      function centroidPoint(lambda, phi) {
          lambda *= radians, phi *= radians;
          var cosPhi = cos$1(phi);
          centroidPointCartesian(cosPhi * cos$1(lambda), cosPhi * sin$1(lambda), sin$1(phi));
      }
  
      function centroidPointCartesian(x, y, z) {
          ++W0;
          X0 += (x - X0) / W0;
          Y0 += (y - Y0) / W0;
          Z0 += (z - Z0) / W0;
      }
  
      function centroidLineStart() {
          centroidStream.point = centroidLinePointFirst;
      }
  
      function centroidLinePointFirst(lambda, phi) {
          lambda *= radians, phi *= radians;
          var cosPhi = cos$1(phi);
          x0 = cosPhi * cos$1(lambda);
          y0 = cosPhi * sin$1(lambda);
          z0 = sin$1(phi);
          centroidStream.point = centroidLinePoint;
          centroidPointCartesian(x0, y0, z0);
      }
  
      function centroidLinePoint(lambda, phi) {
          lambda *= radians, phi *= radians;
          var cosPhi = cos$1(phi),
                  x = cosPhi * cos$1(lambda),
                  y = cosPhi * sin$1(lambda),
                  z = sin$1(phi),
                  w = atan2(sqrt((w = y0 * z - z0 * y) * w + (w = z0 * x - x0 * z) * w + (w = x0 * y - y0 * x) * w), x0 * x + y0 * y + z0 * z);
          W1 += w;
          X1 += w * (x0 + (x0 = x));
          Y1 += w * (y0 + (y0 = y));
          Z1 += w * (z0 + (z0 = z));
          centroidPointCartesian(x0, y0, z0);
      }
  
      function centroidLineEnd() {
          centroidStream.point = centroidPoint;
      }
  
  // See J. E. Brock, The Inertia Tensor for a Spherical Triangle,
  // J. Applied Mechanics 42, 239 (1975).
      function centroidRingStart() {
          centroidStream.point = centroidRingPointFirst;
      }
  
      function centroidRingEnd() {
          centroidRingPoint(lambda00$2, phi00$2);
          centroidStream.point = centroidPoint;
      }
  
      function centroidRingPointFirst(lambda, phi) {
          lambda00$2 = lambda, phi00$2 = phi;
          lambda *= radians, phi *= radians;
          centroidStream.point = centroidRingPoint;
          var cosPhi = cos$1(phi);
          x0 = cosPhi * cos$1(lambda);
          y0 = cosPhi * sin$1(lambda);
          z0 = sin$1(phi);
          centroidPointCartesian(x0, y0, z0);
      }
  
      function centroidRingPoint(lambda, phi) {
          lambda *= radians, phi *= radians;
          var cosPhi = cos$1(phi),
                  x = cosPhi * cos$1(lambda),
                  y = cosPhi * sin$1(lambda),
                  z = sin$1(phi),
                  cx = y0 * z - z0 * y,
                  cy = z0 * x - x0 * z,
                  cz = x0 * y - y0 * x,
                  m = sqrt(cx * cx + cy * cy + cz * cz),
                  w = asin(m), // line weight = angle
                  v = m && -w / m; // area weight multiplier
          X2 += v * cx;
          Y2 += v * cy;
          Z2 += v * cz;
          W1 += w;
          X1 += w * (x0 + (x0 = x));
          Y1 += w * (y0 + (y0 = y));
          Z1 += w * (z0 + (z0 = z));
          centroidPointCartesian(x0, y0, z0);
      }
  
      function centroid(object) {
          W0 = W1 =
                  X0 = Y0 = Z0 =
                  X1 = Y1 = Z1 =
                  X2 = Y2 = Z2 = 0;
          geoStream(object, centroidStream);
  
          var x = X2,
                  y = Y2,
                  z = Z2,
                  m = x * x + y * y + z * z;
  
          // If the area-weighted ccentroid is undefined, fall back to length-weighted ccentroid.
          if (m < epsilon2$1) {
              x = X1, y = Y1, z = Z1;
              // If the feature has zero length, fall back to arithmetic mean of point vectors.
              if (W1 < epsilon$2)
                  x = X0, y = Y0, z = Z0;
              m = x * x + y * y + z * z;
              // If the feature still has an undefined ccentroid, then return.
              if (m < epsilon2$1)
                  return [NaN, NaN];
          }
  
          return [atan2(y, x) * degrees$1, asin(z / sqrt(m)) * degrees$1];
      }
  
      function constant$8(x) {
          return function () {
              return x;
          };
      }
  
      function compose(a, b) {
  
          function compose(x, y) {
              return x = a(x, y), b(x[0], x[1]);
          }
  
          if (a.invert && b.invert)
              compose.invert = function (x, y) {
                  return x = b.invert(x, y), x && a.invert(x[0], x[1]);
              };
  
          return compose;
      }
  
      function rotationIdentity(lambda, phi) {
          return [abs(lambda) > pi$3 ? lambda + Math.round(-lambda / tau$3) * tau$3 : lambda, phi];
      }
  
      rotationIdentity.invert = rotationIdentity;
  
      function rotateRadians(deltaLambda, deltaPhi, deltaGamma) {
          return (deltaLambda %= tau$3) ? (deltaPhi || deltaGamma ? compose(rotationLambda(deltaLambda), rotationPhiGamma(deltaPhi, deltaGamma))
                  : rotationLambda(deltaLambda))
                  : (deltaPhi || deltaGamma ? rotationPhiGamma(deltaPhi, deltaGamma)
                          : rotationIdentity);
      }
  
      function forwardRotationLambda(deltaLambda) {
          return function (lambda, phi) {
              return lambda += deltaLambda, [lambda > pi$3 ? lambda - tau$3 : lambda < -pi$3 ? lambda + tau$3 : lambda, phi];
          };
      }
  
      function rotationLambda(deltaLambda) {
          var rotation = forwardRotationLambda(deltaLambda);
          rotation.invert = forwardRotationLambda(-deltaLambda);
          return rotation;
      }
  
      function rotationPhiGamma(deltaPhi, deltaGamma) {
          var cosDeltaPhi = cos$1(deltaPhi),
                  sinDeltaPhi = sin$1(deltaPhi),
                  cosDeltaGamma = cos$1(deltaGamma),
                  sinDeltaGamma = sin$1(deltaGamma);
  
          function rotation(lambda, phi) {
              var cosPhi = cos$1(phi),
                      x = cos$1(lambda) * cosPhi,
                      y = sin$1(lambda) * cosPhi,
                      z = sin$1(phi),
                      k = z * cosDeltaPhi + x * sinDeltaPhi;
              return [
                  atan2(y * cosDeltaGamma - k * sinDeltaGamma, x * cosDeltaPhi - z * sinDeltaPhi),
                  asin(k * cosDeltaGamma + y * sinDeltaGamma)
              ];
          }
  
          rotation.invert = function (lambda, phi) {
              var cosPhi = cos$1(phi),
                      x = cos$1(lambda) * cosPhi,
                      y = sin$1(lambda) * cosPhi,
                      z = sin$1(phi),
                      k = z * cosDeltaGamma - y * sinDeltaGamma;
              return [
                  atan2(y * cosDeltaGamma + z * sinDeltaGamma, x * cosDeltaPhi + k * sinDeltaPhi),
                  asin(k * cosDeltaPhi - x * sinDeltaPhi)
              ];
          };
  
          return rotation;
      }
  
      function rotation(rotate) {
          rotate = rotateRadians(rotate[0] * radians, rotate[1] * radians, rotate.length > 2 ? rotate[2] * radians : 0);
  
          function forward(coordinates) {
              coordinates = rotate(coordinates[0] * radians, coordinates[1] * radians);
              return coordinates[0] *= degrees$1, coordinates[1] *= degrees$1, coordinates;
          }
  
          forward.invert = function (coordinates) {
              coordinates = rotate.invert(coordinates[0] * radians, coordinates[1] * radians);
              return coordinates[0] *= degrees$1, coordinates[1] *= degrees$1, coordinates;
          };
  
          return forward;
      }
  
  // Generates a circle centered at [0°, 0°], with a given radius and precision.
      function circleStream(stream, radius, delta, direction, t0, t1) {
          if (!delta)
              return;
          var cosRadius = cos$1(radius),
                  sinRadius = sin$1(radius),
                  step = direction * delta;
          if (t0 == null) {
              t0 = radius + direction * tau$3;
              t1 = radius - step / 2;
          } else {
              t0 = circleRadius(cosRadius, t0);
              t1 = circleRadius(cosRadius, t1);
              if (direction > 0 ? t0 < t1 : t0 > t1)
                  t0 += direction * tau$3;
          }
          for (var point, t = t0; direction > 0 ? t > t1 : t < t1; t -= step) {
              point = spherical([cosRadius, -sinRadius * cos$1(t), -sinRadius * sin$1(t)]);
              stream.point(point[0], point[1]);
          }
      }
  
  // Returns the signed angle of a cartesian point relative to [cosRadius, 0, 0].
      function circleRadius(cosRadius, point) {
          point = cartesian(point), point[0] -= cosRadius;
          cartesianNormalizeInPlace(point);
          var radius = acos(-point[1]);
          return ((-point[2] < 0 ? -radius : radius) + tau$3 - epsilon$2) % tau$3;
      }
  
      function circle() {
          var center = constant$8([0, 0]),
                  radius = constant$8(90),
                  precision = constant$8(6),
                  ring,
                  rotate,
                  stream = {point: point};
  
          function point(x, y) {
              ring.push(x = rotate(x, y));
              x[0] *= degrees$1, x[1] *= degrees$1;
          }
  
          function circle() {
              var c = center.apply(this, arguments),
                      r = radius.apply(this, arguments) * radians,
                      p = precision.apply(this, arguments) * radians;
              ring = [];
              rotate = rotateRadians(-c[0] * radians, -c[1] * radians, 0).invert;
              circleStream(stream, r, p, 1);
              c = {type: "Polygon", coordinates: [ring]};
              ring = rotate = null;
              return c;
          }
  
          circle.center = function (_) {
              return arguments.length ? (center = typeof _ === "function" ? _ : constant$8([+_[0], +_[1]]), circle) : center;
          };
  
          circle.radius = function (_) {
              return arguments.length ? (radius = typeof _ === "function" ? _ : constant$8(+_), circle) : radius;
          };
  
          circle.precision = function (_) {
              return arguments.length ? (precision = typeof _ === "function" ? _ : constant$8(+_), circle) : precision;
          };
  
          return circle;
      }
  
      function clipBuffer() {
          var lines = [],
                  line;
          return {
              point: function (x, y) {
                  line.push([x, y]);
              },
              lineStart: function () {
                  lines.push(line = []);
              },
              lineEnd: noop$2,
              rejoin: function () {
                  if (lines.length > 1)
                      lines.push(lines.pop().concat(lines.shift()));
              },
              result: function () {
                  var result = lines;
                  lines = [];
                  line = null;
                  return result;
              }
          };
      }
  
      function pointEqual(a, b) {
          return abs(a[0] - b[0]) < epsilon$2 && abs(a[1] - b[1]) < epsilon$2;
      }
  
      function Intersection(point, points, other, entry) {
          this.x = point;
          this.z = points;
          this.o = other; // another intersection
          this.e = entry; // is an entry?
          this.v = false; // visited
          this.n = this.p = null; // next & previous
      }
  
  // A generalized polygon clipping algorithm: given a polygon that has been cut
  // into its visible line segments, and rejoins the segments by interpolating
  // along the clip edge.
      function clipRejoin(segments, compareIntersection, startInside, interpolate, stream) {
          var subject = [],
                  clip = [],
                  i,
                  n;
  
          segments.forEach(function (segment) {
              if ((n = segment.length - 1) <= 0)
                  return;
              var n, p0 = segment[0], p1 = segment[n], x;
  
              // If the first and last points of a segment are coincident, then treat as a
              // closed ring. TODO if all rings are closed, then the winding order of the
              // exterior ring should be checked.
              if (pointEqual(p0, p1)) {
                  stream.lineStart();
                  for (i = 0; i < n; ++i)
                      stream.point((p0 = segment[i])[0], p0[1]);
                  stream.lineEnd();
                  return;
              }
  
              subject.push(x = new Intersection(p0, segment, null, true));
              clip.push(x.o = new Intersection(p0, null, x, false));
              subject.push(x = new Intersection(p1, segment, null, false));
              clip.push(x.o = new Intersection(p1, null, x, true));
          });
  
          if (!subject.length)
              return;
  
          clip.sort(compareIntersection);
          link$1(subject);
          link$1(clip);
  
          for (i = 0, n = clip.length; i < n; ++i) {
              clip[i].e = startInside = !startInside;
          }
  
          var start = subject[0],
                  points,
                  point;
  
          while (1) {
              // Find first unvisited intersection.
              var current = start,
                      isSubject = true;
              while (current.v)
                  if ((current = current.n) === start)
                      return;
              points = current.z;
              stream.lineStart();
              do {
                  current.v = current.o.v = true;
                  if (current.e) {
                      if (isSubject) {
                          for (i = 0, n = points.length; i < n; ++i)
                              stream.point((point = points[i])[0], point[1]);
                      } else {
                          interpolate(current.x, current.n.x, 1, stream);
                      }
                      current = current.n;
                  } else {
                      if (isSubject) {
                          points = current.p.z;
                          for (i = points.length - 1; i >= 0; --i)
                              stream.point((point = points[i])[0], point[1]);
                      } else {
                          interpolate(current.x, current.p.x, -1, stream);
                      }
                      current = current.p;
                  }
                  current = current.o;
                  points = current.z;
                  isSubject = !isSubject;
              } while (!current.v);
              stream.lineEnd();
          }
      }
  
      function link$1(array) {
          if (!(n = array.length))
              return;
          var n,
                  i = 0,
                  a = array[0],
                  b;
          while (++i < n) {
              a.n = b = array[i];
              b.p = a;
              a = b;
          }
          a.n = b = array[0];
          b.p = a;
      }
  
      var sum$1 = adder();
  
      function longitude(point) {
          if (abs(point[0]) <= pi$3)
              return point[0];
          else
              return sign(point[0]) * ((abs(point[0]) + pi$3) % tau$3 - pi$3);
      }
  
      function polygonContains(polygon, point) {
          var lambda = longitude(point),
                  phi = point[1],
                  sinPhi = sin$1(phi),
                  normal = [sin$1(lambda), -cos$1(lambda), 0],
                  angle = 0,
                  winding = 0;
  
          sum$1.reset();
  
          if (sinPhi === 1)
              phi = halfPi$2 + epsilon$2;
          else if (sinPhi === -1)
              phi = -halfPi$2 - epsilon$2;
  
          for (var i = 0, n = polygon.length; i < n; ++i) {
              if (!(m = (ring = polygon[i]).length))
                  continue;
              var ring,
                      m,
                      point0 = ring[m - 1],
                      lambda0 = longitude(point0),
                      phi0 = point0[1] / 2 + quarterPi,
                      sinPhi0 = sin$1(phi0),
                      cosPhi0 = cos$1(phi0);
  
              for (var j = 0; j < m; ++j, lambda0 = lambda1, sinPhi0 = sinPhi1, cosPhi0 = cosPhi1, point0 = point1) {
                  var point1 = ring[j],
                          lambda1 = longitude(point1),
                          phi1 = point1[1] / 2 + quarterPi,
                          sinPhi1 = sin$1(phi1),
                          cosPhi1 = cos$1(phi1),
                          delta = lambda1 - lambda0,
                          sign = delta >= 0 ? 1 : -1,
                          absDelta = sign * delta,
                          antimeridian = absDelta > pi$3,
                          k = sinPhi0 * sinPhi1;
  
                  sum$1.add(atan2(k * sign * sin$1(absDelta), cosPhi0 * cosPhi1 + k * cos$1(absDelta)));
                  angle += antimeridian ? delta + sign * tau$3 : delta;
  
                  // Are the longitudes either side of the point’s meridian (lambda),
                  // and are the latitudes smaller than the parallel (phi)?
                  if (antimeridian ^ lambda0 >= lambda ^ lambda1 >= lambda) {
                      var arc = cartesianCross(cartesian(point0), cartesian(point1));
                      cartesianNormalizeInPlace(arc);
                      var intersection = cartesianCross(normal, arc);
                      cartesianNormalizeInPlace(intersection);
                      var phiArc = (antimeridian ^ delta >= 0 ? -1 : 1) * asin(intersection[2]);
                      if (phi > phiArc || phi === phiArc && (arc[0] || arc[1])) {
                          winding += antimeridian ^ delta >= 0 ? 1 : -1;
                      }
                  }
              }
          }
  
          // First, determine whether the South pole is inside or outside:
          //
          // It is inside if:
          // * the polygon winds around it in a clockwise direction.
          // * the polygon does not (cumulatively) wind around it, but has a negative
          //   (counter-clockwise) area.
          //
          // Second, count the (signed) number of times a segment crosses a lambda
          // from the point to the South pole.  If it is zero, then the point is the
          // same side as the South pole.
  
          return (angle < -epsilon$2 || angle < epsilon$2 && sum$1 < -epsilon$2) ^ (winding & 1);
      }
  
      function clip(pointVisible, clipLine, interpolate, start) {
          return function (sink) {
              var line = clipLine(sink),
                      ringBuffer = clipBuffer(),
                      ringSink = clipLine(ringBuffer),
                      polygonStarted = false,
                      polygon,
                      segments,
                      ring;
  
              var clip = {
                  point: point,
                  lineStart: lineStart,
                  lineEnd: lineEnd,
                  polygonStart: function () {
                      clip.point = pointRing;
                      clip.lineStart = ringStart;
                      clip.lineEnd = ringEnd;
                      segments = [];
                      polygon = [];
                  },
                  polygonEnd: function () {
                      clip.point = point;
                      clip.lineStart = lineStart;
                      clip.lineEnd = lineEnd;
                      segments = merge(segments);
                      var startInside = polygonContains(polygon, start);
                      if (segments.length) {
                          if (!polygonStarted)
                              sink.polygonStart(), polygonStarted = true;
                          clipRejoin(segments, compareIntersection, startInside, interpolate, sink);
                      } else if (startInside) {
                          if (!polygonStarted)
                              sink.polygonStart(), polygonStarted = true;
                          sink.lineStart();
                          interpolate(null, null, 1, sink);
                          sink.lineEnd();
                      }
                      if (polygonStarted)
                          sink.polygonEnd(), polygonStarted = false;
                      segments = polygon = null;
                  },
                  sphere: function () {
                      sink.polygonStart();
                      sink.lineStart();
                      interpolate(null, null, 1, sink);
                      sink.lineEnd();
                      sink.polygonEnd();
                  }
              };
  
              function point(lambda, phi) {
                  if (pointVisible(lambda, phi))
                      sink.point(lambda, phi);
              }
  
              function pointLine(lambda, phi) {
                  line.point(lambda, phi);
              }
  
              function lineStart() {
                  clip.point = pointLine;
                  line.lineStart();
              }
  
              function lineEnd() {
                  clip.point = point;
                  line.lineEnd();
              }
  
              function pointRing(lambda, phi) {
                  ring.push([lambda, phi]);
                  ringSink.point(lambda, phi);
              }
  
              function ringStart() {
                  ringSink.lineStart();
                  ring = [];
              }
  
              function ringEnd() {
                  pointRing(ring[0][0], ring[0][1]);
                  ringSink.lineEnd();
  
                  var clean = ringSink.clean(),
                          ringSegments = ringBuffer.result(),
                          i, n = ringSegments.length, m,
                          segment,
                          point;
  
                  ring.pop();
                  polygon.push(ring);
                  ring = null;
  
                  if (!n)
                      return;
  
                  // No intersections.
                  if (clean & 1) {
                      segment = ringSegments[0];
                      if ((m = segment.length - 1) > 0) {
                          if (!polygonStarted)
                              sink.polygonStart(), polygonStarted = true;
                          sink.lineStart();
                          for (i = 0; i < m; ++i)
                              sink.point((point = segment[i])[0], point[1]);
                          sink.lineEnd();
                      }
                      return;
                  }
  
                  // Rejoin connected segments.
                  // TODO reuse ringBuffer.rejoin()?
                  if (n > 1 && clean & 2)
                      ringSegments.push(ringSegments.pop().concat(ringSegments.shift()));
  
                  segments.push(ringSegments.filter(validSegment));
              }
  
              return clip;
          };
      }
  
      function validSegment(segment) {
          return segment.length > 1;
      }
  
  // Intersections are sorted along the clip edge. For both antimeridian cutting
  // and circle clipping, the same comparison is used.
      function compareIntersection(a, b) {
          return ((a = a.x)[0] < 0 ? a[1] - halfPi$2 - epsilon$2 : halfPi$2 - a[1])
                  - ((b = b.x)[0] < 0 ? b[1] - halfPi$2 - epsilon$2 : halfPi$2 - b[1]);
      }
  
      var clipAntimeridian = clip(
              function () {
                  return true;
              },
              clipAntimeridianLine,
              clipAntimeridianInterpolate,
              [-pi$3, -halfPi$2]
              );
  
  // Takes a line and cuts into visible segments. Return values: 0 - there were
  // intersections or the line was empty; 1 - no intersections; 2 - there were
  // intersections, and the first and last segments should be rejoined.
      function clipAntimeridianLine(stream) {
          var lambda0 = NaN,
                  phi0 = NaN,
                  sign0 = NaN,
                  clean; // no intersections
  
          return {
              lineStart: function () {
                  stream.lineStart();
                  clean = 1;
              },
              point: function (lambda1, phi1) {
                  var sign1 = lambda1 > 0 ? pi$3 : -pi$3,
                          delta = abs(lambda1 - lambda0);
                  if (abs(delta - pi$3) < epsilon$2) { // line crosses a pole
                      stream.point(lambda0, phi0 = (phi0 + phi1) / 2 > 0 ? halfPi$2 : -halfPi$2);
                      stream.point(sign0, phi0);
                      stream.lineEnd();
                      stream.lineStart();
                      stream.point(sign1, phi0);
                      stream.point(lambda1, phi0);
                      clean = 0;
                  } else if (sign0 !== sign1 && delta >= pi$3) { // line crosses antimeridian
                      if (abs(lambda0 - sign0) < epsilon$2)
                          lambda0 -= sign0 * epsilon$2; // handle degeneracies
                      if (abs(lambda1 - sign1) < epsilon$2)
                          lambda1 -= sign1 * epsilon$2;
                      phi0 = clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1);
                      stream.point(sign0, phi0);
                      stream.lineEnd();
                      stream.lineStart();
                      stream.point(sign1, phi0);
                      clean = 0;
                  }
                  stream.point(lambda0 = lambda1, phi0 = phi1);
                  sign0 = sign1;
              },
              lineEnd: function () {
                  stream.lineEnd();
                  lambda0 = phi0 = NaN;
              },
              clean: function () {
                  return 2 - clean; // if intersections, rejoin first and last segments
              }
          };
      }
  
      function clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1) {
          var cosPhi0,
                  cosPhi1,
                  sinLambda0Lambda1 = sin$1(lambda0 - lambda1);
          return abs(sinLambda0Lambda1) > epsilon$2
                  ? atan((sin$1(phi0) * (cosPhi1 = cos$1(phi1)) * sin$1(lambda1)
                          - sin$1(phi1) * (cosPhi0 = cos$1(phi0)) * sin$1(lambda0))
                          / (cosPhi0 * cosPhi1 * sinLambda0Lambda1))
                          : (phi0 + phi1) / 2;
              }
  
              function clipAntimeridianInterpolate(from, to, direction, stream) {
                  var phi;
                  if (from == null) {
                      phi = direction * halfPi$2;
                      stream.point(-pi$3, phi);
                      stream.point(0, phi);
                      stream.point(pi$3, phi);
                      stream.point(pi$3, 0);
                      stream.point(pi$3, -phi);
                      stream.point(0, -phi);
                      stream.point(-pi$3, -phi);
                      stream.point(-pi$3, 0);
                      stream.point(-pi$3, phi);
                  } else if (abs(from[0] - to[0]) > epsilon$2) {
                      var lambda = from[0] < to[0] ? pi$3 : -pi$3;
                      phi = direction * lambda / 2;
                      stream.point(-lambda, phi);
                      stream.point(0, phi);
                      stream.point(lambda, phi);
                  } else {
                      stream.point(to[0], to[1]);
                  }
              }
  
              function clipCircle(radius) {
                  var cr = cos$1(radius),
                          delta = 6 * radians,
                          smallRadius = cr > 0,
                          notHemisphere = abs(cr) > epsilon$2; // TODO optimise for this common case
  
                  function interpolate(from, to, direction, stream) {
                      circleStream(stream, radius, delta, direction, from, to);
                  }
  
                  function visible(lambda, phi) {
                      return cos$1(lambda) * cos$1(phi) > cr;
                  }
  
                  // Takes a line and cuts into visible segments. Return values used for polygon
                  // clipping: 0 - there were intersections or the line was empty; 1 - no
                  // intersections 2 - there were intersections, and the first and last segments
                  // should be rejoined.
                  function clipLine(stream) {
                      var point0, // previous point
                              c0, // code for previous point
                              v0, // visibility of previous point
                              v00, // visibility of first point
                              clean; // no intersections
                      return {
                          lineStart: function () {
                              v00 = v0 = false;
                              clean = 1;
                          },
                          point: function (lambda, phi) {
                              var point1 = [lambda, phi],
                                      point2,
                                      v = visible(lambda, phi),
                                      c = smallRadius
                                      ? v ? 0 : code(lambda, phi)
                                      : v ? code(lambda + (lambda < 0 ? pi$3 : -pi$3), phi) : 0;
                              if (!point0 && (v00 = v0 = v))
                                  stream.lineStart();
                              // Handle degeneracies.
                              // TODO ignore if not clipping polygons.
                              if (v !== v0) {
                                  point2 = intersect(point0, point1);
                                  if (!point2 || pointEqual(point0, point2) || pointEqual(point1, point2)) {
                                      point1[0] += epsilon$2;
                                      point1[1] += epsilon$2;
                                      v = visible(point1[0], point1[1]);
                                  }
                              }
                              if (v !== v0) {
                                  clean = 0;
                                  if (v) {
                                      // outside going in
                                      stream.lineStart();
                                      point2 = intersect(point1, point0);
                                      stream.point(point2[0], point2[1]);
                                  } else {
                                      // inside going out
                                      point2 = intersect(point0, point1);
                                      stream.point(point2[0], point2[1]);
                                      stream.lineEnd();
                                  }
                                  point0 = point2;
                              } else if (notHemisphere && point0 && smallRadius ^ v) {
                                  var t;
                                  // If the codes for two points are different, or are both zero,
                                  // and there this segment intersects with the small circle.
                                  if (!(c & c0) && (t = intersect(point1, point0, true))) {
                                      clean = 0;
                                      if (smallRadius) {
                                          stream.lineStart();
                                          stream.point(t[0][0], t[0][1]);
                                          stream.point(t[1][0], t[1][1]);
                                          stream.lineEnd();
                                      } else {
                                          stream.point(t[1][0], t[1][1]);
                                          stream.lineEnd();
                                          stream.lineStart();
                                          stream.point(t[0][0], t[0][1]);
                                      }
                                  }
                              }
                              if (v && (!point0 || !pointEqual(point0, point1))) {
                                  stream.point(point1[0], point1[1]);
                              }
                              point0 = point1, v0 = v, c0 = c;
                          },
                          lineEnd: function () {
                              if (v0)
                                  stream.lineEnd();
                              point0 = null;
                          },
                          // Rejoin first and last segments if there were intersections and the first
                          // and last points were visible.
                          clean: function () {
                              return clean | ((v00 && v0) << 1);
                          }
                      };
                  }
  
                  // Intersects the great circle between a and b with the clip circle.
                  function intersect(a, b, two) {
                      var pa = cartesian(a),
                              pb = cartesian(b);
  
                      // We have two planes, n1.p = d1 and n2.p = d2.
                      // Find intersection line p(t) = c1 n1 + c2 n2 + t (n1 ⨯ n2).
                      var n1 = [1, 0, 0], // normal
                              n2 = cartesianCross(pa, pb),
                              n2n2 = cartesianDot(n2, n2),
                              n1n2 = n2[0], // cartesianDot(n1, n2),
                              determinant = n2n2 - n1n2 * n1n2;
  
                      // Two polar points.
                      if (!determinant)
                          return !two && a;
  
                      var c1 = cr * n2n2 / determinant,
                              c2 = -cr * n1n2 / determinant,
                              n1xn2 = cartesianCross(n1, n2),
                              A = cartesianScale(n1, c1),
                              B = cartesianScale(n2, c2);
                      cartesianAddInPlace(A, B);
  
                      // Solve |p(t)|^2 = 1.
                      var u = n1xn2,
                              w = cartesianDot(A, u),
                              uu = cartesianDot(u, u),
                              t2 = w * w - uu * (cartesianDot(A, A) - 1);
  
                      if (t2 < 0)
                          return;
  
                      var t = sqrt(t2),
                              q = cartesianScale(u, (-w - t) / uu);
                      cartesianAddInPlace(q, A);
                      q = spherical(q);
  
                      if (!two)
                          return q;
  
                      // Two intersection points.
                      var lambda0 = a[0],
                              lambda1 = b[0],
                              phi0 = a[1],
                              phi1 = b[1],
                              z;
  
                      if (lambda1 < lambda0)
                          z = lambda0, lambda0 = lambda1, lambda1 = z;
  
                      var delta = lambda1 - lambda0,
                              polar = abs(delta - pi$3) < epsilon$2,
                              meridian = polar || delta < epsilon$2;
  
                      if (!polar && phi1 < phi0)
                          z = phi0, phi0 = phi1, phi1 = z;
  
                      // Check that the first point is between a and b.
                      if (meridian
                              ? polar
                              ? phi0 + phi1 > 0 ^ q[1] < (abs(q[0] - lambda0) < epsilon$2 ? phi0 : phi1)
                              : phi0 <= q[1] && q[1] <= phi1
                              : delta > pi$3 ^ (lambda0 <= q[0] && q[0] <= lambda1)) {
                          var q1 = cartesianScale(u, (-w + t) / uu);
                          cartesianAddInPlace(q1, A);
                          return [q, spherical(q1)];
                      }
                  }
  
                  // Generates a 4-bit vector representing the location of a point relative to
                  // the small circle's bounding box.
                  function code(lambda, phi) {
                      var r = smallRadius ? radius : pi$3 - radius,
                              code = 0;
                      if (lambda < -r)
                          code |= 1; // left
                      else if (lambda > r)
                          code |= 2; // right
                      if (phi < -r)
                          code |= 4; // below
                      else if (phi > r)
                          code |= 8; // above
                      return code;
                  }
  
                  return clip(visible, clipLine, interpolate, smallRadius ? [0, -radius] : [-pi$3, radius - pi$3]);
              }
  
              function clipLine(a, b, x0, y0, x1, y1) {
                  var ax = a[0],
                          ay = a[1],
                          bx = b[0],
                          by = b[1],
                          t0 = 0,
                          t1 = 1,
                          dx = bx - ax,
                          dy = by - ay,
                          r;
  
                  r = x0 - ax;
                  if (!dx && r > 0)
                      return;
                  r /= dx;
                  if (dx < 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  } else if (dx > 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  }
  
                  r = x1 - ax;
                  if (!dx && r < 0)
                      return;
                  r /= dx;
                  if (dx < 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  } else if (dx > 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  }
  
                  r = y0 - ay;
                  if (!dy && r > 0)
                      return;
                  r /= dy;
                  if (dy < 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  } else if (dy > 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  }
  
                  r = y1 - ay;
                  if (!dy && r < 0)
                      return;
                  r /= dy;
                  if (dy < 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  } else if (dy > 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  }
  
                  if (t0 > 0)
                      a[0] = ax + t0 * dx, a[1] = ay + t0 * dy;
                  if (t1 < 1)
                      b[0] = ax + t1 * dx, b[1] = ay + t1 * dy;
                  return true;
              }
  
              var clipMax = 1e9, clipMin = -clipMax;
  
  // TODO Use d3-polygon’s polygonContains here for the ring check?
  // TODO Eliminate duplicate buffering in clipBuffer and polygon.push?
  
              function clipRectangle(x0, y0, x1, y1) {
  
                  function visible(x, y) {
                      return x0 <= x && x <= x1 && y0 <= y && y <= y1;
                  }
  
                  function interpolate(from, to, direction, stream) {
                      var a = 0, a1 = 0;
                      if (from == null
                              || (a = corner(from, direction)) !== (a1 = corner(to, direction))
                              || comparePoint(from, to) < 0 ^ direction > 0) {
                          do
                              stream.point(a === 0 || a === 3 ? x0 : x1, a > 1 ? y1 : y0);
                          while ((a = (a + direction + 4) % 4) !== a1);
                      } else {
                          stream.point(to[0], to[1]);
                      }
                  }
  
                  function corner(p, direction) {
                      return abs(p[0] - x0) < epsilon$2 ? direction > 0 ? 0 : 3
                              : abs(p[0] - x1) < epsilon$2 ? direction > 0 ? 2 : 1
                              : abs(p[1] - y0) < epsilon$2 ? direction > 0 ? 1 : 0
                              : direction > 0 ? 3 : 2; // abs(p[1] - y1) < epsilon
                  }
  
                  function compareIntersection(a, b) {
                      return comparePoint(a.x, b.x);
                  }
  
                  function comparePoint(a, b) {
                      var ca = corner(a, 1),
                              cb = corner(b, 1);
                      return ca !== cb ? ca - cb
                              : ca === 0 ? b[1] - a[1]
                              : ca === 1 ? a[0] - b[0]
                              : ca === 2 ? a[1] - b[1]
                              : b[0] - a[0];
                  }
  
                  return function (stream) {
                      var activeStream = stream,
                              bufferStream = clipBuffer(),
                              segments,
                              polygon,
                              ring,
                              x__, y__, v__, // first point
                              x_, y_, v_, // previous point
                              first,
                              clean;
  
                      var clipStream = {
                          point: point,
                          lineStart: lineStart,
                          lineEnd: lineEnd,
                          polygonStart: polygonStart,
                          polygonEnd: polygonEnd
                      };
  
                      function point(x, y) {
                          if (visible(x, y))
                              activeStream.point(x, y);
                      }
  
                      function polygonInside() {
                          var winding = 0;
  
                          for (var i = 0, n = polygon.length; i < n; ++i) {
                              for (var ring = polygon[i], j = 1, m = ring.length, point = ring[0], a0, a1, b0 = point[0], b1 = point[1]; j < m; ++j) {
                                  a0 = b0, a1 = b1, point = ring[j], b0 = point[0], b1 = point[1];
                                  if (a1 <= y1) {
                                      if (b1 > y1 && (b0 - a0) * (y1 - a1) > (b1 - a1) * (x0 - a0))
                                          ++winding;
                                  } else {
                                      if (b1 <= y1 && (b0 - a0) * (y1 - a1) < (b1 - a1) * (x0 - a0))
                                          --winding;
                                  }
                              }
                          }
  
                          return winding;
                      }
  
                      // Buffer geometry within a polygon and then clip it en masse.
                      function polygonStart() {
                          activeStream = bufferStream, segments = [], polygon = [], clean = true;
                      }
  
                      function polygonEnd() {
                          var startInside = polygonInside(),
                                  cleanInside = clean && startInside,
                                  visible = (segments = merge(segments)).length;
                          if (cleanInside || visible) {
                              stream.polygonStart();
                              if (cleanInside) {
                                  stream.lineStart();
                                  interpolate(null, null, 1, stream);
                                  stream.lineEnd();
                              }
                              if (visible) {
                                  clipRejoin(segments, compareIntersection, startInside, interpolate, stream);
                              }
                              stream.polygonEnd();
                          }
                          activeStream = stream, segments = polygon = ring = null;
                      }
  
                      function lineStart() {
                          clipStream.point = linePoint;
                          if (polygon)
                              polygon.push(ring = []);
                          first = true;
                          v_ = false;
                          x_ = y_ = NaN;
                      }
  
                      // TODO rather than special-case polygons, simply handle them separately.
                      // Ideally, coincident intersection points should be jittered to avoid
                      // clipping issues.
                      function lineEnd() {
                          if (segments) {
                              linePoint(x__, y__);
                              if (v__ && v_)
                                  bufferStream.rejoin();
                              segments.push(bufferStream.result());
                          }
                          clipStream.point = point;
                          if (v_)
                              activeStream.lineEnd();
                      }
  
                      function linePoint(x, y) {
                          var v = visible(x, y);
                          if (polygon)
                              ring.push([x, y]);
                          if (first) {
                              x__ = x, y__ = y, v__ = v;
                              first = false;
                              if (v) {
                                  activeStream.lineStart();
                                  activeStream.point(x, y);
                              }
                          } else {
                              if (v && v_)
                                  activeStream.point(x, y);
                              else {
                                  var a = [x_ = Math.max(clipMin, Math.min(clipMax, x_)), y_ = Math.max(clipMin, Math.min(clipMax, y_))],
                                          b = [x = Math.max(clipMin, Math.min(clipMax, x)), y = Math.max(clipMin, Math.min(clipMax, y))];
                                  if (clipLine(a, b, x0, y0, x1, y1)) {
                                      if (!v_) {
                                          activeStream.lineStart();
                                          activeStream.point(a[0], a[1]);
                                      }
                                      activeStream.point(b[0], b[1]);
                                      if (!v)
                                          activeStream.lineEnd();
                                      clean = false;
                                  } else if (v) {
                                      activeStream.lineStart();
                                      activeStream.point(x, y);
                                      clean = false;
                                  }
                              }
                          }
                          x_ = x, y_ = y, v_ = v;
                      }
  
                      return clipStream;
                  };
              }
  
              function extent$1() {
                  var x0 = 0,
                          y0 = 0,
                          x1 = 960,
                          y1 = 500,
                          cache,
                          cacheStream,
                          clip;
  
                  return clip = {
                      stream: function (stream) {
                          return cache && cacheStream === stream ? cache : cache = clipRectangle(x0, y0, x1, y1)(cacheStream = stream);
                      },
                      extent: function (_) {
                          return arguments.length ? (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1], cache = cacheStream = null, clip) : [[x0, y0], [x1, y1]];
                      }
                  };
              }
  
              var lengthSum = adder(),
                      lambda0$2,
                      sinPhi0$1,
                      cosPhi0$1;
  
              var lengthStream = {
                  sphere: noop$2,
                  point: noop$2,
                  lineStart: lengthLineStart,
                  lineEnd: noop$2,
                  polygonStart: noop$2,
                  polygonEnd: noop$2
              };
  
              function lengthLineStart() {
                  lengthStream.point = lengthPointFirst;
                  lengthStream.lineEnd = lengthLineEnd;
              }
  
              function lengthLineEnd() {
                  lengthStream.point = lengthStream.lineEnd = noop$2;
              }
  
              function lengthPointFirst(lambda, phi) {
                  lambda *= radians, phi *= radians;
                  lambda0$2 = lambda, sinPhi0$1 = sin$1(phi), cosPhi0$1 = cos$1(phi);
                  lengthStream.point = lengthPoint;
              }
  
              function lengthPoint(lambda, phi) {
                  lambda *= radians, phi *= radians;
                  var sinPhi = sin$1(phi),
                          cosPhi = cos$1(phi),
                          delta = abs(lambda - lambda0$2),
                          cosDelta = cos$1(delta),
                          sinDelta = sin$1(delta),
                          x = cosPhi * sinDelta,
                          y = cosPhi0$1 * sinPhi - sinPhi0$1 * cosPhi * cosDelta,
                          z = sinPhi0$1 * sinPhi + cosPhi0$1 * cosPhi * cosDelta;
                  lengthSum.add(atan2(sqrt(x * x + y * y), z));
                  lambda0$2 = lambda, sinPhi0$1 = sinPhi, cosPhi0$1 = cosPhi;
              }
  
              function length$1(object) {
                  lengthSum.reset();
                  geoStream(object, lengthStream);
                  return +lengthSum;
              }
  
              var coordinates = [null, null],
                      object$1 = {type: "LineString", coordinates: coordinates};
  
              function distance(a, b) {
                  coordinates[0] = a;
                  coordinates[1] = b;
                  return length$1(object$1);
              }
  
              var containsObjectType = {
                  Feature: function (object, point) {
                      return containsGeometry(object.geometry, point);
                  },
                  FeatureCollection: function (object, point) {
                      var features = object.features, i = -1, n = features.length;
                      while (++i < n)
                          if (containsGeometry(features[i].geometry, point))
                              return true;
                      return false;
                  }
              };
  
              var containsGeometryType = {
                  Sphere: function () {
                      return true;
                  },
                  Point: function (object, point) {
                      return containsPoint(object.coordinates, point);
                  },
                  MultiPoint: function (object, point) {
                      var coordinates = object.coordinates, i = -1, n = coordinates.length;
                      while (++i < n)
                          if (containsPoint(coordinates[i], point))
                              return true;
                      return false;
                  },
                  LineString: function (object, point) {
                      return containsLine(object.coordinates, point);
                  },
                  MultiLineString: function (object, point) {
                      var coordinates = object.coordinates, i = -1, n = coordinates.length;
                      while (++i < n)
                          if (containsLine(coordinates[i], point))
                              return true;
                      return false;
                  },
                  Polygon: function (object, point) {
                      return containsPolygon(object.coordinates, point);
                  },
                  MultiPolygon: function (object, point) {
                      var coordinates = object.coordinates, i = -1, n = coordinates.length;
                      while (++i < n)
                          if (containsPolygon(coordinates[i], point))
                              return true;
                      return false;
                  },
                  GeometryCollection: function (object, point) {
                      var geometries = object.geometries, i = -1, n = geometries.length;
                      while (++i < n)
                          if (containsGeometry(geometries[i], point))
                              return true;
                      return false;
                  }
              };
  
              function containsGeometry(geometry, point) {
                  return geometry && containsGeometryType.hasOwnProperty(geometry.type)
                          ? containsGeometryType[geometry.type](geometry, point)
                          : false;
              }
  
              function containsPoint(coordinates, point) {
                  return distance(coordinates, point) === 0;
              }
  
              function containsLine(coordinates, point) {
                  var ao, bo, ab;
                  for (var i = 0, n = coordinates.length; i < n; i++) {
                      bo = distance(coordinates[i], point);
                      if (bo === 0)
                          return true;
                      if (i > 0) {
                          ab = distance(coordinates[i], coordinates[i - 1]);
                          if (
                                  ab > 0 &&
                                  ao <= ab &&
                                  bo <= ab &&
                                  (ao + bo - ab) * (1 - Math.pow((ao - bo) / ab, 2)) < epsilon2$1 * ab
                                  )
                              return true;
                      }
                      ao = bo;
                  }
                  return false;
              }
  
              function containsPolygon(coordinates, point) {
                  return !!polygonContains(coordinates.map(ringRadians), pointRadians(point));
              }
  
              function ringRadians(ring) {
                  return ring = ring.map(pointRadians), ring.pop(), ring;
              }
  
              function pointRadians(point) {
                  return [point[0] * radians, point[1] * radians];
              }
  
              function contains$1(object, point) {
                  return (object && containsObjectType.hasOwnProperty(object.type)
                          ? containsObjectType[object.type]
                          : containsGeometry)(object, point);
              }
  
              function graticuleX(y0, y1, dy) {
                  var y = sequence(y0, y1 - epsilon$2, dy).concat(y1);
                  return function (x) {
                      return y.map(function (y) {
                          return [x, y];
                      });
                  };
              }
  
              function graticuleY(x0, x1, dx) {
                  var x = sequence(x0, x1 - epsilon$2, dx).concat(x1);
                  return function (y) {
                      return x.map(function (x) {
                          return [x, y];
                      });
                  };
              }
  
              function graticule() {
                  var x1, x0, X1, X0,
                          y1, y0, Y1, Y0,
                          dx = 10, dy = dx, DX = 90, DY = 360,
                          x, y, X, Y,
                          precision = 2.5;
  
                  function graticule() {
                      return {type: "MultiLineString", coordinates: lines()};
                  }
  
                  function lines() {
                      return sequence(ceil(X0 / DX) * DX, X1, DX).map(X)
                              .concat(sequence(ceil(Y0 / DY) * DY, Y1, DY).map(Y))
                              .concat(sequence(ceil(x0 / dx) * dx, x1, dx).filter(function (x) {
                                  return abs(x % DX) > epsilon$2;
                              }).map(x))
                              .concat(sequence(ceil(y0 / dy) * dy, y1, dy).filter(function (y) {
                                  return abs(y % DY) > epsilon$2;
                              }).map(y));
                  }
  
                  graticule.lines = function () {
                      return lines().map(function (coordinates) {
                          return {type: "LineString", coordinates: coordinates};
                      });
                  };
  
                  graticule.outline = function () {
                      return {
                          type: "Polygon",
                          coordinates: [
                              X(X0).concat(
                                      Y(Y1).slice(1),
                                      X(X1).reverse().slice(1),
                                      Y(Y0).reverse().slice(1))
                          ]
                      };
                  };
  
                  graticule.extent = function (_) {
                      if (!arguments.length)
                          return graticule.extentMinor();
                      return graticule.extentMajor(_).extentMinor(_);
                  };
  
                  graticule.extentMajor = function (_) {
                      if (!arguments.length)
                          return [[X0, Y0], [X1, Y1]];
                      X0 = +_[0][0], X1 = +_[1][0];
                      Y0 = +_[0][1], Y1 = +_[1][1];
                      if (X0 > X1)
                          _ = X0, X0 = X1, X1 = _;
                      if (Y0 > Y1)
                          _ = Y0, Y0 = Y1, Y1 = _;
                      return graticule.precision(precision);
                  };
  
                  graticule.extentMinor = function (_) {
                      if (!arguments.length)
                          return [[x0, y0], [x1, y1]];
                      x0 = +_[0][0], x1 = +_[1][0];
                      y0 = +_[0][1], y1 = +_[1][1];
                      if (x0 > x1)
                          _ = x0, x0 = x1, x1 = _;
                      if (y0 > y1)
                          _ = y0, y0 = y1, y1 = _;
                      return graticule.precision(precision);
                  };
  
                  graticule.step = function (_) {
                      if (!arguments.length)
                          return graticule.stepMinor();
                      return graticule.stepMajor(_).stepMinor(_);
                  };
  
                  graticule.stepMajor = function (_) {
                      if (!arguments.length)
                          return [DX, DY];
                      DX = +_[0], DY = +_[1];
                      return graticule;
                  };
  
                  graticule.stepMinor = function (_) {
                      if (!arguments.length)
                          return [dx, dy];
                      dx = +_[0], dy = +_[1];
                      return graticule;
                  };
  
                  graticule.precision = function (_) {
                      if (!arguments.length)
                          return precision;
                      precision = +_;
                      x = graticuleX(y0, y1, 90);
                      y = graticuleY(x0, x1, precision);
                      X = graticuleX(Y0, Y1, 90);
                      Y = graticuleY(X0, X1, precision);
                      return graticule;
                  };
  
                  return graticule
                          .extentMajor([[-180, -90 + epsilon$2], [180, 90 - epsilon$2]])
                          .extentMinor([[-180, -80 - epsilon$2], [180, 80 + epsilon$2]]);
              }
  
              function graticule10() {
                  return graticule()();
              }
  
              function interpolate$1(a, b) {
                  var x0 = a[0] * radians,
                          y0 = a[1] * radians,
                          x1 = b[0] * radians,
                          y1 = b[1] * radians,
                          cy0 = cos$1(y0),
                          sy0 = sin$1(y0),
                          cy1 = cos$1(y1),
                          sy1 = sin$1(y1),
                          kx0 = cy0 * cos$1(x0),
                          ky0 = cy0 * sin$1(x0),
                          kx1 = cy1 * cos$1(x1),
                          ky1 = cy1 * sin$1(x1),
                          d = 2 * asin(sqrt(haversin(y1 - y0) + cy0 * cy1 * haversin(x1 - x0))),
                          k = sin$1(d);
  
                  var interpolate = d ? function (t) {
                      var B = sin$1(t *= d) / k,
                              A = sin$1(d - t) / k,
                              x = A * kx0 + B * kx1,
                              y = A * ky0 + B * ky1,
                              z = A * sy0 + B * sy1;
                      return [
                          atan2(y, x) * degrees$1,
                          atan2(z, sqrt(x * x + y * y)) * degrees$1
                      ];
                  } : function () {
                      return [x0 * degrees$1, y0 * degrees$1];
                  };
  
                  interpolate.distance = d;
  
                  return interpolate;
              }
  
              function identity$4(x) {
                  return x;
              }
  
              var areaSum$1 = adder(),
                      areaRingSum$1 = adder(),
                      x00,
                      y00,
                      x0$1,
                      y0$1;
  
              var areaStream$1 = {
                  point: noop$2,
                  lineStart: noop$2,
                  lineEnd: noop$2,
                  polygonStart: function () {
                      areaStream$1.lineStart = areaRingStart$1;
                      areaStream$1.lineEnd = areaRingEnd$1;
                  },
                  polygonEnd: function () {
                      areaStream$1.lineStart = areaStream$1.lineEnd = areaStream$1.point = noop$2;
                      areaSum$1.add(abs(areaRingSum$1));
                      areaRingSum$1.reset();
                  },
                  result: function () {
                      var area = areaSum$1 / 2;
                      areaSum$1.reset();
                      return area;
                  }
              };
  
              function areaRingStart$1() {
                  areaStream$1.point = areaPointFirst$1;
              }
  
              function areaPointFirst$1(x, y) {
                  areaStream$1.point = areaPoint$1;
                  x00 = x0$1 = x, y00 = y0$1 = y;
              }
  
              function areaPoint$1(x, y) {
                  areaRingSum$1.add(y0$1 * x - x0$1 * y);
                  x0$1 = x, y0$1 = y;
              }
  
              function areaRingEnd$1() {
                  areaPoint$1(x00, y00);
              }
  
              var x0$2 = Infinity,
                      y0$2 = x0$2,
                      x1 = -x0$2,
                      y1 = x1;
  
              var boundsStream$1 = {
                  point: boundsPoint$1,
                  lineStart: noop$2,
                  lineEnd: noop$2,
                  polygonStart: noop$2,
                  polygonEnd: noop$2,
                  result: function () {
                      var bounds = [[x0$2, y0$2], [x1, y1]];
                      x1 = y1 = -(y0$2 = x0$2 = Infinity);
                      return bounds;
                  }
              };
  
              function boundsPoint$1(x, y) {
                  if (x < x0$2)
                      x0$2 = x;
                  if (x > x1)
                      x1 = x;
                  if (y < y0$2)
                      y0$2 = y;
                  if (y > y1)
                      y1 = y;
              }
  
  // TODO Enforce positive area for exterior, negative area for interior?
  
              var X0$1 = 0,
                      Y0$1 = 0,
                      Z0$1 = 0,
                      X1$1 = 0,
                      Y1$1 = 0,
                      Z1$1 = 0,
                      X2$1 = 0,
                      Y2$1 = 0,
                      Z2$1 = 0,
                      x00$1,
                      y00$1,
                      x0$3,
                      y0$3;
  
              var centroidStream$1 = {
                  point: centroidPoint$1,
                  lineStart: centroidLineStart$1,
                  lineEnd: centroidLineEnd$1,
                  polygonStart: function () {
                      centroidStream$1.lineStart = centroidRingStart$1;
                      centroidStream$1.lineEnd = centroidRingEnd$1;
                  },
                  polygonEnd: function () {
                      centroidStream$1.point = centroidPoint$1;
                      centroidStream$1.lineStart = centroidLineStart$1;
                      centroidStream$1.lineEnd = centroidLineEnd$1;
                  },
                  result: function () {
                      var centroid = Z2$1 ? [X2$1 / Z2$1, Y2$1 / Z2$1]
                              : Z1$1 ? [X1$1 / Z1$1, Y1$1 / Z1$1]
                              : Z0$1 ? [X0$1 / Z0$1, Y0$1 / Z0$1]
                              : [NaN, NaN];
                      X0$1 = Y0$1 = Z0$1 =
                              X1$1 = Y1$1 = Z1$1 =
                              X2$1 = Y2$1 = Z2$1 = 0;
                      return centroid;
                  }
              };
  
              function centroidPoint$1(x, y) {
                  X0$1 += x;
                  Y0$1 += y;
                  ++Z0$1;
              }
  
              function centroidLineStart$1() {
                  centroidStream$1.point = centroidPointFirstLine;
              }
  
              function centroidPointFirstLine(x, y) {
                  centroidStream$1.point = centroidPointLine;
                  centroidPoint$1(x0$3 = x, y0$3 = y);
              }
  
              function centroidPointLine(x, y) {
                  var dx = x - x0$3, dy = y - y0$3, z = sqrt(dx * dx + dy * dy);
                  X1$1 += z * (x0$3 + x) / 2;
                  Y1$1 += z * (y0$3 + y) / 2;
                  Z1$1 += z;
                  centroidPoint$1(x0$3 = x, y0$3 = y);
              }
  
              function centroidLineEnd$1() {
                  centroidStream$1.point = centroidPoint$1;
              }
  
              function centroidRingStart$1() {
                  centroidStream$1.point = centroidPointFirstRing;
              }
  
              function centroidRingEnd$1() {
                  centroidPointRing(x00$1, y00$1);
              }
  
              function centroidPointFirstRing(x, y) {
                  centroidStream$1.point = centroidPointRing;
                  centroidPoint$1(x00$1 = x0$3 = x, y00$1 = y0$3 = y);
              }
  
              function centroidPointRing(x, y) {
                  var dx = x - x0$3,
                          dy = y - y0$3,
                          z = sqrt(dx * dx + dy * dy);
  
                  X1$1 += z * (x0$3 + x) / 2;
                  Y1$1 += z * (y0$3 + y) / 2;
                  Z1$1 += z;
  
                  z = y0$3 * x - x0$3 * y;
                  X2$1 += z * (x0$3 + x);
                  Y2$1 += z * (y0$3 + y);
                  Z2$1 += z * 3;
                  centroidPoint$1(x0$3 = x, y0$3 = y);
              }
  
              function PathContext(context) {
                  this._context = context;
              }
  
              PathContext.prototype = {
                  _radius: 4.5,
                  pointRadius: function (_) {
                      return this._radius = _, this;
                  },
                  polygonStart: function () {
                      this._line = 0;
                  },
                  polygonEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line === 0)
                          this._context.closePath();
                      this._point = NaN;
                  },
                  point: function (x, y) {
                      switch (this._point) {
                          case 0:
                          {
                              this._context.moveTo(x, y);
                              this._point = 1;
                              break;
                          }
                          case 1:
                          {
                              this._context.lineTo(x, y);
                              break;
                          }
                          default:
                          {
                              this._context.moveTo(x + this._radius, y);
                              this._context.arc(x, y, this._radius, 0, tau$3);
                              break;
                          }
                      }
                  },
                  result: noop$2
              };
  
              var lengthSum$1 = adder(),
                      lengthRing,
                      x00$2,
                      y00$2,
                      x0$4,
                      y0$4;
  
              var lengthStream$1 = {
                  point: noop$2,
                  lineStart: function () {
                      lengthStream$1.point = lengthPointFirst$1;
                  },
                  lineEnd: function () {
                      if (lengthRing)
                          lengthPoint$1(x00$2, y00$2);
                      lengthStream$1.point = noop$2;
                  },
                  polygonStart: function () {
                      lengthRing = true;
                  },
                  polygonEnd: function () {
                      lengthRing = null;
                  },
                  result: function () {
                      var length = +lengthSum$1;
                      lengthSum$1.reset();
                      return length;
                  }
              };
  
              function lengthPointFirst$1(x, y) {
                  lengthStream$1.point = lengthPoint$1;
                  x00$2 = x0$4 = x, y00$2 = y0$4 = y;
              }
  
              function lengthPoint$1(x, y) {
                  x0$4 -= x, y0$4 -= y;
                  lengthSum$1.add(sqrt(x0$4 * x0$4 + y0$4 * y0$4));
                  x0$4 = x, y0$4 = y;
              }
  
              function PathString() {
                  this._string = [];
              }
  
              PathString.prototype = {
                  _radius: 4.5,
                  _circle: circle$1(4.5),
                  pointRadius: function (_) {
                      if ((_ = +_) !== this._radius)
                          this._radius = _, this._circle = null;
                      return this;
                  },
                  polygonStart: function () {
                      this._line = 0;
                  },
                  polygonEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line === 0)
                          this._string.push("Z");
                      this._point = NaN;
                  },
                  point: function (x, y) {
                      switch (this._point) {
                          case 0:
                          {
                              this._string.push("M", x, ",", y);
                              this._point = 1;
                              break;
                          }
                          case 1:
                          {
                              this._string.push("L", x, ",", y);
                              break;
                          }
                          default:
                          {
                              if (this._circle == null)
                                  this._circle = circle$1(this._radius);
                              this._string.push("M", x, ",", y, this._circle);
                              break;
                          }
                      }
                  },
                  result: function () {
                      if (this._string.length) {
                          var result = this._string.join("");
                          this._string = [];
                          return result;
                      } else {
                          return null;
                      }
                  }
              };
  
              function circle$1(radius) {
                  return "m0," + radius
                          + "a" + radius + "," + radius + " 0 1,1 0," + -2 * radius
                          + "a" + radius + "," + radius + " 0 1,1 0," + 2 * radius
                          + "z";
              }
  
              function index$1(projection, context) {
                  var pointRadius = 4.5,
                          projectionStream,
                          contextStream;
  
                  function path(object) {
                      if (object) {
                          if (typeof pointRadius === "function")
                              contextStream.pointRadius(+pointRadius.apply(this, arguments));
                          geoStream(object, projectionStream(contextStream));
                      }
                      return contextStream.result();
                  }
  
                  path.area = function (object) {
                      geoStream(object, projectionStream(areaStream$1));
                      return areaStream$1.result();
                  };
  
                  path.measure = function (object) {
                      geoStream(object, projectionStream(lengthStream$1));
                      return lengthStream$1.result();
                  };
  
                  path.bounds = function (object) {
                      geoStream(object, projectionStream(boundsStream$1));
                      return boundsStream$1.result();
                  };
  
                  path.centroid = function (object) {
                      geoStream(object, projectionStream(centroidStream$1));
                      return centroidStream$1.result();
                  };
  
                  path.projection = function (_) {
                      return arguments.length ? (projectionStream = _ == null ? (projection = null, identity$4) : (projection = _).stream, path) : projection;
                  };
  
                  path.context = function (_) {
                      if (!arguments.length)
                          return context;
                      contextStream = _ == null ? (context = null, new PathString) : new PathContext(context = _);
                      if (typeof pointRadius !== "function")
                          contextStream.pointRadius(pointRadius);
                      return path;
                  };
  
                  path.pointRadius = function (_) {
                      if (!arguments.length)
                          return pointRadius;
                      pointRadius = typeof _ === "function" ? _ : (contextStream.pointRadius(+_), +_);
                      return path;
                  };
  
                  return path.projection(projection).context(context);
              }
  
              function transform(methods) {
                  return {
                      stream: transformer(methods)
                  };
              }
  
              function transformer(methods) {
                  return function (stream) {
                      var s = new TransformStream;
                      for (var key in methods)
                          s[key] = methods[key];
                      s.stream = stream;
                      return s;
                  };
              }
  
              function TransformStream() {}
  
              TransformStream.prototype = {
                  constructor: TransformStream,
                  point: function (x, y) {
                      this.stream.point(x, y);
                  },
                  sphere: function () {
                      this.stream.sphere();
                  },
                  lineStart: function () {
                      this.stream.lineStart();
                  },
                  lineEnd: function () {
                      this.stream.lineEnd();
                  },
                  polygonStart: function () {
                      this.stream.polygonStart();
                  },
                  polygonEnd: function () {
                      this.stream.polygonEnd();
                  }
              };
  
              function fit(projection, fitBounds, object) {
                  var clip = projection.clipExtent && projection.clipExtent();
                  projection.scale(150).translate([0, 0]);
                  if (clip != null)
                      projection.clipExtent(null);
                  geoStream(object, projection.stream(boundsStream$1));
                  fitBounds(boundsStream$1.result());
                  if (clip != null)
                      projection.clipExtent(clip);
                  return projection;
              }
  
              function fitExtent(projection, extent, object) {
                  return fit(projection, function (b) {
                      var w = extent[1][0] - extent[0][0],
                              h = extent[1][1] - extent[0][1],
                              k = Math.min(w / (b[1][0] - b[0][0]), h / (b[1][1] - b[0][1])),
                              x = +extent[0][0] + (w - k * (b[1][0] + b[0][0])) / 2,
                              y = +extent[0][1] + (h - k * (b[1][1] + b[0][1])) / 2;
                      projection.scale(150 * k).translate([x, y]);
                  }, object);
              }
  
              function fitSize(projection, size, object) {
                  return fitExtent(projection, [[0, 0], size], object);
              }
  
              function fitWidth(projection, width, object) {
                  return fit(projection, function (b) {
                      var w = +width,
                              k = w / (b[1][0] - b[0][0]),
                              x = (w - k * (b[1][0] + b[0][0])) / 2,
                              y = -k * b[0][1];
                      projection.scale(150 * k).translate([x, y]);
                  }, object);
              }
  
              function fitHeight(projection, height, object) {
                  return fit(projection, function (b) {
                      var h = +height,
                              k = h / (b[1][1] - b[0][1]),
                              x = -k * b[0][0],
                              y = (h - k * (b[1][1] + b[0][1])) / 2;
                      projection.scale(150 * k).translate([x, y]);
                  }, object);
              }
  
              var maxDepth = 16, // maximum depth of subdivision
                      cosMinDistance = cos$1(30 * radians); // cos(minimum angular distance)
  
              function resample(project, delta2) {
                  return +delta2 ? resample$1(project, delta2) : resampleNone(project);
              }
  
              function resampleNone(project) {
                  return transformer({
                      point: function (x, y) {
                          x = project(x, y);
                          this.stream.point(x[0], x[1]);
                      }
                  });
              }
  
              function resample$1(project, delta2) {
  
                  function resampleLineTo(x0, y0, lambda0, a0, b0, c0, x1, y1, lambda1, a1, b1, c1, depth, stream) {
                      var dx = x1 - x0,
                              dy = y1 - y0,
                              d2 = dx * dx + dy * dy;
                      if (d2 > 4 * delta2 && depth--) {
                          var a = a0 + a1,
                                  b = b0 + b1,
                                  c = c0 + c1,
                                  m = sqrt(a * a + b * b + c * c),
                                  phi2 = asin(c /= m),
                                  lambda2 = abs(abs(c) - 1) < epsilon$2 || abs(lambda0 - lambda1) < epsilon$2 ? (lambda0 + lambda1) / 2 : atan2(b, a),
                                  p = project(lambda2, phi2),
                                  x2 = p[0],
                                  y2 = p[1],
                                  dx2 = x2 - x0,
                                  dy2 = y2 - y0,
                                  dz = dy * dx2 - dx * dy2;
                          if (dz * dz / d2 > delta2 // perpendicular projected distance
                                  || abs((dx * dx2 + dy * dy2) / d2 - 0.5) > 0.3 // midpoint close to an end
                                  || a0 * a1 + b0 * b1 + c0 * c1 < cosMinDistance) { // angular distance
                              resampleLineTo(x0, y0, lambda0, a0, b0, c0, x2, y2, lambda2, a /= m, b /= m, c, depth, stream);
                              stream.point(x2, y2);
                              resampleLineTo(x2, y2, lambda2, a, b, c, x1, y1, lambda1, a1, b1, c1, depth, stream);
                          }
                      }
                  }
                  return function (stream) {
                      var lambda00, x00, y00, a00, b00, c00, // first point
                              lambda0, x0, y0, a0, b0, c0; // previous point
  
                      var resampleStream = {
                          point: point,
                          lineStart: lineStart,
                          lineEnd: lineEnd,
                          polygonStart: function () {
                              stream.polygonStart();
                              resampleStream.lineStart = ringStart;
                          },
                          polygonEnd: function () {
                              stream.polygonEnd();
                              resampleStream.lineStart = lineStart;
                          }
                      };
  
                      function point(x, y) {
                          x = project(x, y);
                          stream.point(x[0], x[1]);
                      }
  
                      function lineStart() {
                          x0 = NaN;
                          resampleStream.point = linePoint;
                          stream.lineStart();
                      }
  
                      function linePoint(lambda, phi) {
                          var c = cartesian([lambda, phi]), p = project(lambda, phi);
                          resampleLineTo(x0, y0, lambda0, a0, b0, c0, x0 = p[0], y0 = p[1], lambda0 = lambda, a0 = c[0], b0 = c[1], c0 = c[2], maxDepth, stream);
                          stream.point(x0, y0);
                      }
  
                      function lineEnd() {
                          resampleStream.point = point;
                          stream.lineEnd();
                      }
  
                      function ringStart() {
                          lineStart();
                          resampleStream.point = ringPoint;
                          resampleStream.lineEnd = ringEnd;
                      }
  
                      function ringPoint(lambda, phi) {
                          linePoint(lambda00 = lambda, phi), x00 = x0, y00 = y0, a00 = a0, b00 = b0, c00 = c0;
                          resampleStream.point = linePoint;
                      }
  
                      function ringEnd() {
                          resampleLineTo(x0, y0, lambda0, a0, b0, c0, x00, y00, lambda00, a00, b00, c00, maxDepth, stream);
                          resampleStream.lineEnd = lineEnd;
                          lineEnd();
                      }
  
                      return resampleStream;
                  };
              }
  
              var transformRadians = transformer({
                  point: function (x, y) {
                      this.stream.point(x * radians, y * radians);
                  }
              });
  
              function transformRotate(rotate) {
                  return transformer({
                      point: function (x, y) {
                          var r = rotate(x, y);
                          return this.stream.point(r[0], r[1]);
                      }
                  });
              }
  
              function scaleTranslate(k, dx, dy, sx, sy) {
                  function transform(x, y) {
                      x *= sx;
                      y *= sy;
                      return [dx + k * x, dy - k * y];
                  }
                  transform.invert = function (x, y) {
                      return [(x - dx) / k * sx, (dy - y) / k * sy];
                  };
                  return transform;
              }
  
              function scaleTranslateRotate(k, dx, dy, sx, sy, alpha) {
                  var cosAlpha = cos$1(alpha),
                          sinAlpha = sin$1(alpha),
                          a = cosAlpha * k,
                          b = sinAlpha * k,
                          ai = cosAlpha / k,
                          bi = sinAlpha / k,
                          ci = (sinAlpha * dy - cosAlpha * dx) / k,
                          fi = (sinAlpha * dx + cosAlpha * dy) / k;
                  function transform(x, y) {
                      x *= sx;
                      y *= sy;
                      return [a * x - b * y + dx, dy - b * x - a * y];
                  }
                  transform.invert = function (x, y) {
                      return [sx * (ai * x - bi * y + ci), sy * (fi - bi * x - ai * y)];
                  };
                  return transform;
              }
  
              function projection(project) {
                  return projectionMutator(function () {
                      return project;
                  })();
              }
  
              function projectionMutator(projectAt) {
                  var project,
                          k = 150, // scale
                          x = 480, y = 250, // translate
                          lambda = 0, phi = 0, // center
                          deltaLambda = 0, deltaPhi = 0, deltaGamma = 0, rotate, // pre-rotate
                          alpha = 0, // post-rotate angle
                          sx = 1, // reflectX
                          sy = 1, // reflectX
                          theta = null, preclip = clipAntimeridian, // pre-clip angle
                          x0 = null, y0, x1, y1, postclip = identity$4, // post-clip extent
                          delta2 = 0.5, // precision
                          projectResample,
                          projectTransform,
                          projectRotateTransform,
                          cache,
                          cacheStream;
  
                  function projection(point) {
                      return projectRotateTransform(point[0] * radians, point[1] * radians);
                  }
  
                  function invert(point) {
                      point = projectRotateTransform.invert(point[0], point[1]);
                      return point && [point[0] * degrees$1, point[1] * degrees$1];
                  }
  
                  projection.stream = function (stream) {
                      return cache && cacheStream === stream ? cache : cache = transformRadians(transformRotate(rotate)(preclip(projectResample(postclip(cacheStream = stream)))));
                  };
  
                  projection.preclip = function (_) {
                      return arguments.length ? (preclip = _, theta = undefined, reset()) : preclip;
                  };
  
                  projection.postclip = function (_) {
                      return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip;
                  };
  
                  projection.clipAngle = function (_) {
                      return arguments.length ? (preclip = +_ ? clipCircle(theta = _ * radians) : (theta = null, clipAntimeridian), reset()) : theta * degrees$1;
                  };
  
                  projection.clipExtent = function (_) {
                      return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$4) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]];
                  };
  
                  projection.scale = function (_) {
                      return arguments.length ? (k = +_, recenter()) : k;
                  };
  
                  projection.translate = function (_) {
                      return arguments.length ? (x = +_[0], y = +_[1], recenter()) : [x, y];
                  };
  
                  projection.center = function (_) {
                      return arguments.length ? (lambda = _[0] % 360 * radians, phi = _[1] % 360 * radians, recenter()) : [lambda * degrees$1, phi * degrees$1];
                  };
  
                  projection.rotate = function (_) {
                      return arguments.length ? (deltaLambda = _[0] % 360 * radians, deltaPhi = _[1] % 360 * radians, deltaGamma = _.length > 2 ? _[2] % 360 * radians : 0, recenter()) : [deltaLambda * degrees$1, deltaPhi * degrees$1, deltaGamma * degrees$1];
                  };
  
                  projection.angle = function (_) {
                      return arguments.length ? (alpha = _ % 360 * radians, recenter()) : alpha * degrees$1;
                  };
  
                  projection.reflectX = function (_) {
                      return arguments.length ? (sx = _ ? -1 : 1, recenter()) : sx < 0;
                  };
  
                  projection.reflectY = function (_) {
                      return arguments.length ? (sy = _ ? -1 : 1, recenter()) : sy < 0;
                  };
  
                  projection.precision = function (_) {
                      return arguments.length ? (projectResample = resample(projectTransform, delta2 = _ * _), reset()) : sqrt(delta2);
                  };
  
                  projection.fitExtent = function (extent, object) {
                      return fitExtent(projection, extent, object);
                  };
  
                  projection.fitSize = function (size, object) {
                      return fitSize(projection, size, object);
                  };
  
                  projection.fitWidth = function (width, object) {
                      return fitWidth(projection, width, object);
                  };
  
                  projection.fitHeight = function (height, object) {
                      return fitHeight(projection, height, object);
                  };
  
                  function recenter() {
                      var center = scaleTranslateRotate(k, 0, 0, sx, sy, alpha).apply(null, project(lambda, phi)),
                              transform = (alpha ? scaleTranslateRotate : scaleTranslate)(k, x - center[0], y - center[1], sx, sy, alpha);
                      rotate = rotateRadians(deltaLambda, deltaPhi, deltaGamma);
                      projectTransform = compose(project, transform);
                      projectRotateTransform = compose(rotate, projectTransform);
                      projectResample = resample(projectTransform, delta2);
                      return reset();
                  }
  
                  function reset() {
                      cache = cacheStream = null;
                      return projection;
                  }
  
                  return function () {
                      project = projectAt.apply(this, arguments);
                      projection.invert = project.invert && invert;
                      return recenter();
                  };
              }
  
              function conicProjection(projectAt) {
                  var phi0 = 0,
                          phi1 = pi$3 / 3,
                          m = projectionMutator(projectAt),
                          p = m(phi0, phi1);
  
                  p.parallels = function (_) {
                      return arguments.length ? m(phi0 = _[0] * radians, phi1 = _[1] * radians) : [phi0 * degrees$1, phi1 * degrees$1];
                  };
  
                  return p;
              }
  
              function cylindricalEqualAreaRaw(phi0) {
                  var cosPhi0 = cos$1(phi0);
  
                  function forward(lambda, phi) {
                      return [lambda * cosPhi0, sin$1(phi) / cosPhi0];
                  }
  
                  forward.invert = function (x, y) {
                      return [x / cosPhi0, asin(y * cosPhi0)];
                  };
  
                  return forward;
              }
  
              function conicEqualAreaRaw(y0, y1) {
                  var sy0 = sin$1(y0), n = (sy0 + sin$1(y1)) / 2;
  
                  // Are the parallels symmetrical around the Equator?
                  if (abs(n) < epsilon$2)
                      return cylindricalEqualAreaRaw(y0);
  
                  var c = 1 + sy0 * (2 * n - sy0), r0 = sqrt(c) / n;
  
                  function project(x, y) {
                      var r = sqrt(c - 2 * n * sin$1(y)) / n;
                      return [r * sin$1(x *= n), r0 - r * cos$1(x)];
                  }
  
                  project.invert = function (x, y) {
                      var r0y = r0 - y,
                              l = atan2(x, abs(r0y)) * sign(r0y);
                      if (r0y * n < 0)
                          l -= pi$3 * sign(x) * sign(r0y);
                      return [l / n, asin((c - (x * x + r0y * r0y) * n * n) / (2 * n))];
                  };
  
                  return project;
              }
  
              function conicEqualArea() {
                  return conicProjection(conicEqualAreaRaw)
                          .scale(155.424)
                          .center([0, 33.6442]);
              }
  
              function albers() {
                  return conicEqualArea()
                          .parallels([29.5, 45.5])
                          .scale(1070)
                          .translate([480, 250])
                          .rotate([96, 0])
                          .center([-0.6, 38.7]);
              }
  
  // The projections must have mutually exclusive clip regions on the sphere,
  // as this will avoid emitting interleaving lines and polygons.
              function multiplex(streams) {
                  var n = streams.length;
                  return {
                      point: function (x, y) {
                          var i = -1;
                          while (++i < n)
                              streams[i].point(x, y);
                      },
                      sphere: function () {
                          var i = -1;
                          while (++i < n)
                              streams[i].sphere();
                      },
                      lineStart: function () {
                          var i = -1;
                          while (++i < n)
                              streams[i].lineStart();
                      },
                      lineEnd: function () {
                          var i = -1;
                          while (++i < n)
                              streams[i].lineEnd();
                      },
                      polygonStart: function () {
                          var i = -1;
                          while (++i < n)
                              streams[i].polygonStart();
                      },
                      polygonEnd: function () {
                          var i = -1;
                          while (++i < n)
                              streams[i].polygonEnd();
                      }
                  };
              }
  
  // A composite projection for the United States, configured by default for
  // 960×500. The projection also works quite well at 960×600 if you change the
  // scale to 1285 and adjust the translate accordingly. The set of standard
  // parallels for each region comes from USGS, which is published here:
  // http://egsc.usgs.gov/isb/pubs/MapProjections/projections.html#albers
              function albersUsa() {
                  var cache,
                          cacheStream,
                          lower48 = albers(), lower48Point,
                          alaska = conicEqualArea().rotate([154, 0]).center([-2, 58.5]).parallels([55, 65]), alaskaPoint, // EPSG:3338
                          hawaii = conicEqualArea().rotate([157, 0]).center([-3, 19.9]).parallels([8, 18]), hawaiiPoint, // ESRI:102007
                          point, pointStream = {point: function (x, y) {
                                  point = [x, y];
                              }};
  
                  function albersUsa(coordinates) {
                      var x = coordinates[0], y = coordinates[1];
                      return point = null,
                              (lower48Point.point(x, y), point)
                              || (alaskaPoint.point(x, y), point)
                              || (hawaiiPoint.point(x, y), point);
                  }
  
                  albersUsa.invert = function (coordinates) {
                      var k = lower48.scale(),
                              t = lower48.translate(),
                              x = (coordinates[0] - t[0]) / k,
                              y = (coordinates[1] - t[1]) / k;
                      return (y >= 0.120 && y < 0.234 && x >= -0.425 && x < -0.214 ? alaska
                              : y >= 0.166 && y < 0.234 && x >= -0.214 && x < -0.115 ? hawaii
                              : lower48).invert(coordinates);
                  };
  
                  albersUsa.stream = function (stream) {
                      return cache && cacheStream === stream ? cache : cache = multiplex([lower48.stream(cacheStream = stream), alaska.stream(stream), hawaii.stream(stream)]);
                  };
  
                  albersUsa.precision = function (_) {
                      if (!arguments.length)
                          return lower48.precision();
                      lower48.precision(_), alaska.precision(_), hawaii.precision(_);
                      return reset();
                  };
  
                  albersUsa.scale = function (_) {
                      if (!arguments.length)
                          return lower48.scale();
                      lower48.scale(_), alaska.scale(_ * 0.35), hawaii.scale(_);
                      return albersUsa.translate(lower48.translate());
                  };
  
                  albersUsa.translate = function (_) {
                      if (!arguments.length)
                          return lower48.translate();
                      var k = lower48.scale(), x = +_[0], y = +_[1];
  
                      lower48Point = lower48
                              .translate(_)
                              .clipExtent([[x - 0.455 * k, y - 0.238 * k], [x + 0.455 * k, y + 0.238 * k]])
                              .stream(pointStream);
  
                      alaskaPoint = alaska
                              .translate([x - 0.307 * k, y + 0.201 * k])
                              .clipExtent([[x - 0.425 * k + epsilon$2, y + 0.120 * k + epsilon$2], [x - 0.214 * k - epsilon$2, y + 0.234 * k - epsilon$2]])
                              .stream(pointStream);
  
                      hawaiiPoint = hawaii
                              .translate([x - 0.205 * k, y + 0.212 * k])
                              .clipExtent([[x - 0.214 * k + epsilon$2, y + 0.166 * k + epsilon$2], [x - 0.115 * k - epsilon$2, y + 0.234 * k - epsilon$2]])
                              .stream(pointStream);
  
                      return reset();
                  };
  
                  albersUsa.fitExtent = function (extent, object) {
                      return fitExtent(albersUsa, extent, object);
                  };
  
                  albersUsa.fitSize = function (size, object) {
                      return fitSize(albersUsa, size, object);
                  };
  
                  albersUsa.fitWidth = function (width, object) {
                      return fitWidth(albersUsa, width, object);
                  };
  
                  albersUsa.fitHeight = function (height, object) {
                      return fitHeight(albersUsa, height, object);
                  };
  
                  function reset() {
                      cache = cacheStream = null;
                      return albersUsa;
                  }
  
                  return albersUsa.scale(1070);
              }
  
              function azimuthalRaw(scale) {
                  return function (x, y) {
                      var cx = cos$1(x),
                              cy = cos$1(y),
                              k = scale(cx * cy);
                      return [
                          k * cy * sin$1(x),
                          k * sin$1(y)
                      ];
                  }
              }
  
              function azimuthalInvert(angle) {
                  return function (x, y) {
                      var z = sqrt(x * x + y * y),
                              c = angle(z),
                              sc = sin$1(c),
                              cc = cos$1(c);
                      return [
                          atan2(x * sc, z * cc),
                          asin(z && y * sc / z)
                      ];
                  }
              }
  
              var azimuthalEqualAreaRaw = azimuthalRaw(function (cxcy) {
                  return sqrt(2 / (1 + cxcy));
              });
  
              azimuthalEqualAreaRaw.invert = azimuthalInvert(function (z) {
                  return 2 * asin(z / 2);
              });
  
              function azimuthalEqualArea() {
                  return projection(azimuthalEqualAreaRaw)
                          .scale(124.75)
                          .clipAngle(180 - 1e-3);
              }
  
              var azimuthalEquidistantRaw = azimuthalRaw(function (c) {
                  return (c = acos(c)) && c / sin$1(c);
              });
  
              azimuthalEquidistantRaw.invert = azimuthalInvert(function (z) {
                  return z;
              });
  
              function azimuthalEquidistant() {
                  return projection(azimuthalEquidistantRaw)
                          .scale(79.4188)
                          .clipAngle(180 - 1e-3);
              }
  
              function mercatorRaw(lambda, phi) {
                  return [lambda, log(tan((halfPi$2 + phi) / 2))];
              }
  
              mercatorRaw.invert = function (x, y) {
                  return [x, 2 * atan(exp(y)) - halfPi$2];
              };
  
              function mercator() {
                  return mercatorProjection(mercatorRaw)
                          .scale(961 / tau$3);
              }
  
              function mercatorProjection(project) {
                  var m = projection(project),
                          center = m.center,
                          scale = m.scale,
                          translate = m.translate,
                          clipExtent = m.clipExtent,
                          x0 = null, y0, x1, y1; // clip extent
  
                  m.scale = function (_) {
                      return arguments.length ? (scale(_), reclip()) : scale();
                  };
  
                  m.translate = function (_) {
                      return arguments.length ? (translate(_), reclip()) : translate();
                  };
  
                  m.center = function (_) {
                      return arguments.length ? (center(_), reclip()) : center();
                  };
  
                  m.clipExtent = function (_) {
                      return arguments.length ? ((_ == null ? x0 = y0 = x1 = y1 = null : (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1])), reclip()) : x0 == null ? null : [[x0, y0], [x1, y1]];
                  };
  
                  function reclip() {
                      var k = pi$3 * scale(),
                              t = m(rotation(m.rotate()).invert([0, 0]));
                      return clipExtent(x0 == null
                              ? [[t[0] - k, t[1] - k], [t[0] + k, t[1] + k]] : project === mercatorRaw
                              ? [[Math.max(t[0] - k, x0), y0], [Math.min(t[0] + k, x1), y1]]
                              : [[x0, Math.max(t[1] - k, y0)], [x1, Math.min(t[1] + k, y1)]]);
                  }
  
                  return reclip();
              }
  
              function tany(y) {
                  return tan((halfPi$2 + y) / 2);
              }
  
              function conicConformalRaw(y0, y1) {
                  var cy0 = cos$1(y0),
                          n = y0 === y1 ? sin$1(y0) : log(cy0 / cos$1(y1)) / log(tany(y1) / tany(y0)),
                          f = cy0 * pow(tany(y0), n) / n;
  
                  if (!n)
                      return mercatorRaw;
  
                  function project(x, y) {
                      if (f > 0) {
                          if (y < -halfPi$2 + epsilon$2)
                              y = -halfPi$2 + epsilon$2;
                      } else {
                          if (y > halfPi$2 - epsilon$2)
                              y = halfPi$2 - epsilon$2;
                      }
                      var r = f / pow(tany(y), n);
                      return [r * sin$1(n * x), f - r * cos$1(n * x)];
                  }
  
                  project.invert = function (x, y) {
                      var fy = f - y, r = sign(n) * sqrt(x * x + fy * fy),
                              l = atan2(x, abs(fy)) * sign(fy);
                      if (fy * n < 0)
                          l -= pi$3 * sign(x) * sign(fy);
                      return [l / n, 2 * atan(pow(f / r, 1 / n)) - halfPi$2];
                  };
  
                  return project;
              }
  
              function conicConformal() {
                  return conicProjection(conicConformalRaw)
                          .scale(109.5)
                          .parallels([30, 30]);
              }
  
              function equirectangularRaw(lambda, phi) {
                  return [lambda, phi];
              }
  
              equirectangularRaw.invert = equirectangularRaw;
  
              function equirectangular() {
                  return projection(equirectangularRaw)
                          .scale(152.63);
              }
  
              function conicEquidistantRaw(y0, y1) {
                  var cy0 = cos$1(y0),
                          n = y0 === y1 ? sin$1(y0) : (cy0 - cos$1(y1)) / (y1 - y0),
                          g = cy0 / n + y0;
  
                  if (abs(n) < epsilon$2)
                      return equirectangularRaw;
  
                  function project(x, y) {
                      var gy = g - y, nx = n * x;
                      return [gy * sin$1(nx), g - gy * cos$1(nx)];
                  }
  
                  project.invert = function (x, y) {
                      var gy = g - y,
                              l = atan2(x, abs(gy)) * sign(gy);
                      if (gy * n < 0)
                          l -= pi$3 * sign(x) * sign(gy);
                      return [l / n, g - sign(n) * sqrt(x * x + gy * gy)];
                  };
  
                  return project;
              }
  
              function conicEquidistant() {
                  return conicProjection(conicEquidistantRaw)
                          .scale(131.154)
                          .center([0, 13.9389]);
              }
  
              var A1 = 1.340264,
                      A2 = -0.081106,
                      A3 = 0.000893,
                      A4 = 0.003796,
                      M = sqrt(3) / 2,
                      iterations = 12;
  
              function equalEarthRaw(lambda, phi) {
                  var l = asin(M * sin$1(phi)), l2 = l * l, l6 = l2 * l2 * l2;
                  return [
                      lambda * cos$1(l) / (M * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2))),
                      l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2))
                  ];
              }
  
              equalEarthRaw.invert = function (x, y) {
                  var l = y, l2 = l * l, l6 = l2 * l2 * l2;
                  for (var i = 0, delta, fy, fpy; i < iterations; ++i) {
                      fy = l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2)) - y;
                      fpy = A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2);
                      l -= delta = fy / fpy, l2 = l * l, l6 = l2 * l2 * l2;
                      if (abs(delta) < epsilon2$1)
                          break;
                  }
                  return [
                      M * x * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2)) / cos$1(l),
                      asin(sin$1(l) / M)
                  ];
              };
  
              function equalEarth() {
                  return projection(equalEarthRaw)
                          .scale(177.158);
              }
  
              function gnomonicRaw(x, y) {
                  var cy = cos$1(y), k = cos$1(x) * cy;
                  return [cy * sin$1(x) / k, sin$1(y) / k];
              }
  
              gnomonicRaw.invert = azimuthalInvert(atan);
  
              function gnomonic() {
                  return projection(gnomonicRaw)
                          .scale(144.049)
                          .clipAngle(60);
              }
  
              function identity$5() {
                  var k = 1, tx = 0, ty = 0, sx = 1, sy = 1, // scale, translate and reflect
                          alpha = 0, ca, sa, // angle
                          x0 = null, y0, x1, y1, // clip extent
                          kx = 1, ky = 1,
                          transform = transformer({
                              point: function (x, y) {
                                  var p = projection([x, y]);
                                  this.stream.point(p[0], p[1]);
                              }
                          }),
                          postclip = identity$4,
                          cache,
                          cacheStream;
  
                  function reset() {
                      kx = k * sx;
                      ky = k * sy;
                      cache = cacheStream = null;
                      return projection;
                  }
  
                  function projection(p) {
                      var x = p[0] * kx, y = p[1] * ky;
                      if (alpha) {
                          var t = y * ca - x * sa;
                          x = x * ca + y * sa;
                          y = t;
                      }
                      return [x + tx, y + ty];
                  }
                  projection.invert = function (p) {
                      var x = p[0] - tx, y = p[1] - ty;
                      if (alpha) {
                          var t = y * ca + x * sa;
                          x = x * ca - y * sa;
                          y = t;
                      }
                      return [x / kx, y / ky];
                  };
                  projection.stream = function (stream) {
                      return cache && cacheStream === stream ? cache : cache = transform(postclip(cacheStream = stream));
                  };
                  projection.postclip = function (_) {
                      return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip;
                  };
                  projection.clipExtent = function (_) {
                      return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$4) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]];
                  };
                  projection.scale = function (_) {
                      return arguments.length ? (k = +_, reset()) : k;
                  };
                  projection.translate = function (_) {
                      return arguments.length ? (tx = +_[0], ty = +_[1], reset()) : [tx, ty];
                  };
                  projection.angle = function (_) {
                      return arguments.length ? (alpha = _ % 360 * radians, sa = sin$1(alpha), ca = cos$1(alpha), reset()) : alpha * degrees$1;
                  };
                  projection.reflectX = function (_) {
                      return arguments.length ? (sx = _ ? -1 : 1, reset()) : sx < 0;
                  };
                  projection.reflectY = function (_) {
                      return arguments.length ? (sy = _ ? -1 : 1, reset()) : sy < 0;
                  };
                  projection.fitExtent = function (extent, object) {
                      return fitExtent(projection, extent, object);
                  };
                  projection.fitSize = function (size, object) {
                      return fitSize(projection, size, object);
                  };
                  projection.fitWidth = function (width, object) {
                      return fitWidth(projection, width, object);
                  };
                  projection.fitHeight = function (height, object) {
                      return fitHeight(projection, height, object);
                  };
  
                  return projection;
              }
  
              function naturalEarth1Raw(lambda, phi) {
                  var phi2 = phi * phi, phi4 = phi2 * phi2;
                  return [
                      lambda * (0.8707 - 0.131979 * phi2 + phi4 * (-0.013791 + phi4 * (0.003971 * phi2 - 0.001529 * phi4))),
                      phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4)))
                  ];
              }
  
              naturalEarth1Raw.invert = function (x, y) {
                  var phi = y, i = 25, delta;
                  do {
                      var phi2 = phi * phi, phi4 = phi2 * phi2;
                      phi -= delta = (phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4))) - y) /
                              (1.007226 + phi2 * (0.015085 * 3 + phi4 * (-0.044475 * 7 + 0.028874 * 9 * phi2 - 0.005916 * 11 * phi4)));
                  } while (abs(delta) > epsilon$2 && --i > 0);
                  return [
                      x / (0.8707 + (phi2 = phi * phi) * (-0.131979 + phi2 * (-0.013791 + phi2 * phi2 * phi2 * (0.003971 - 0.001529 * phi2)))),
                      phi
                  ];
              };
  
              function naturalEarth1() {
                  return projection(naturalEarth1Raw)
                          .scale(175.295);
              }
  
              function orthographicRaw(x, y) {
                  return [cos$1(y) * sin$1(x), sin$1(y)];
              }
  
              orthographicRaw.invert = azimuthalInvert(asin);
  
              function orthographic() {
                  return projection(orthographicRaw)
                          .scale(249.5)
                          .clipAngle(90 + epsilon$2);
              }
  
              function stereographicRaw(x, y) {
                  var cy = cos$1(y), k = 1 + cos$1(x) * cy;
                  return [cy * sin$1(x) / k, sin$1(y) / k];
              }
  
              stereographicRaw.invert = azimuthalInvert(function (z) {
                  return 2 * atan(z);
              });
  
              function stereographic() {
                  return projection(stereographicRaw)
                          .scale(250)
                          .clipAngle(142);
              }
  
              function transverseMercatorRaw(lambda, phi) {
                  return [log(tan((halfPi$2 + phi) / 2)), -lambda];
              }
  
              transverseMercatorRaw.invert = function (x, y) {
                  return [-y, 2 * atan(exp(x)) - halfPi$2];
              };
  
              function transverseMercator() {
                  var m = mercatorProjection(transverseMercatorRaw),
                          center = m.center,
                          rotate = m.rotate;
  
                  m.center = function (_) {
                      return arguments.length ? center([-_[1], _[0]]) : (_ = center(), [_[1], -_[0]]);
                  };
  
                  m.rotate = function (_) {
                      return arguments.length ? rotate([_[0], _[1], _.length > 2 ? _[2] + 90 : 90]) : (_ = rotate(), [_[0], _[1], _[2] - 90]);
                  };
  
                  return rotate([0, 0, 90])
                          .scale(159.155);
              }
  
              function defaultSeparation(a, b) {
                  return a.parent === b.parent ? 1 : 2;
              }
  
              function meanX(children) {
                  return children.reduce(meanXReduce, 0) / children.length;
              }
  
              function meanXReduce(x, c) {
                  return x + c.x;
              }
  
              function maxY(children) {
                  return 1 + children.reduce(maxYReduce, 0);
              }
  
              function maxYReduce(y, c) {
                  return Math.max(y, c.y);
              }
  
              function leafLeft(node) {
                  var children;
                  while (children = node.children)
                      node = children[0];
                  return node;
              }
  
              function leafRight(node) {
                  var children;
                  while (children = node.children)
                      node = children[children.length - 1];
                  return node;
              }
  
              function cluster() {
                  var separation = defaultSeparation,
                          dx = 1,
                          dy = 1,
                          nodeSize = false;
  
                  function cluster(root) {
                      var previousNode,
                              x = 0;
  
                      // First walk, computing the initial x & y values.
                      root.eachAfter(function (node) {
                          var children = node.children;
                          if (children) {
                              node.x = meanX(children);
                              node.y = maxY(children);
                          } else {
                              node.x = previousNode ? x += separation(node, previousNode) : 0;
                              node.y = 0;
                              previousNode = node;
                          }
                      });
  
                      var left = leafLeft(root),
                              right = leafRight(root),
                              x0 = left.x - separation(left, right) / 2,
                              x1 = right.x + separation(right, left) / 2;
  
                      // Second walk, normalizing x & y to the desired size.
                      return root.eachAfter(nodeSize ? function (node) {
                          node.x = (node.x - root.x) * dx;
                          node.y = (root.y - node.y) * dy;
                      } : function (node) {
                          node.x = (node.x - x0) / (x1 - x0) * dx;
                          node.y = (1 - (root.y ? node.y / root.y : 1)) * dy;
                      });
                  }
  
                  cluster.separation = function (x) {
                      return arguments.length ? (separation = x, cluster) : separation;
                  };
  
                  cluster.size = function (x) {
                      return arguments.length ? (nodeSize = false, dx = +x[0], dy = +x[1], cluster) : (nodeSize ? null : [dx, dy]);
                  };
  
                  cluster.nodeSize = function (x) {
                      return arguments.length ? (nodeSize = true, dx = +x[0], dy = +x[1], cluster) : (nodeSize ? [dx, dy] : null);
                  };
  
                  return cluster;
              }
  
              function count(node) {
                  var sum = 0,
                          children = node.children,
                          i = children && children.length;
                  if (!i)
                      sum = 1;
                  else
                      while (--i >= 0)
                          sum += children[i].value;
                  node.value = sum;
              }
  
              function node_count() {
                  return this.eachAfter(count);
              }
  
              function node_each(callback) {
                  var node = this, current, next = [node], children, i, n;
                  do {
                      current = next.reverse(), next = [];
                      while (node = current.pop()) {
                          callback(node), children = node.children;
                          if (children)
                              for (i = 0, n = children.length; i < n; ++i) {
                                  next.push(children[i]);
                              }
                      }
                  } while (next.length);
                  return this;
              }
  
              function node_eachBefore(callback) {
                  var node = this, nodes = [node], children, i;
                  while (node = nodes.pop()) {
                      callback(node), children = node.children;
                      if (children)
                          for (i = children.length - 1; i >= 0; --i) {
                              nodes.push(children[i]);
                          }
                  }
                  return this;
              }
  
              function node_eachAfter(callback) {
                  var node = this, nodes = [node], next = [], children, i, n;
                  while (node = nodes.pop()) {
                      next.push(node), children = node.children;
                      if (children)
                          for (i = 0, n = children.length; i < n; ++i) {
                              nodes.push(children[i]);
                          }
                  }
                  while (node = next.pop()) {
                      callback(node);
                  }
                  return this;
              }
  
              function node_sum(value) {
                  return this.eachAfter(function (node) {
                      var sum = +value(node.data) || 0,
                              children = node.children,
                              i = children && children.length;
                      while (--i >= 0)
                          sum += children[i].value;
                      node.value = sum;
                  });
              }
  
              function node_sort(compare) {
                  return this.eachBefore(function (node) {
                      if (node.children) {
                          node.children.sort(compare);
                      }
                  });
              }
  
              function node_path(end) {
                  var start = this,
                          ancestor = leastCommonAncestor(start, end),
                          nodes = [start];
                  while (start !== ancestor) {
                      start = start.parent;
                      nodes.push(start);
                  }
                  var k = nodes.length;
                  while (end !== ancestor) {
                      nodes.splice(k, 0, end);
                      end = end.parent;
                  }
                  return nodes;
              }
  
              function leastCommonAncestor(a, b) {
                  if (a === b)
                      return a;
                  var aNodes = a.ancestors(),
                          bNodes = b.ancestors(),
                          c = null;
                  a = aNodes.pop();
                  b = bNodes.pop();
                  while (a === b) {
                      c = a;
                      a = aNodes.pop();
                      b = bNodes.pop();
                  }
                  return c;
              }
  
              function node_ancestors() {
                  var node = this, nodes = [node];
                  while (node = node.parent) {
                      nodes.push(node);
                  }
                  return nodes;
              }
  
              function node_descendants() {
                  var nodes = [];
                  this.each(function (node) {
                      nodes.push(node);
                  });
                  return nodes;
              }
  
              function node_leaves() {
                  var leaves = [];
                  this.eachBefore(function (node) {
                      if (!node.children) {
                          leaves.push(node);
                      }
                  });
                  return leaves;
              }
  
              function node_links() {
                  var root = this, links = [];
                  root.each(function (node) {
                      if (node !== root) { // Don’t include the root’s parent, if any.
                          links.push({source: node.parent, target: node});
                      }
                  });
                  return links;
              }
  
              function hierarchy(data, children) {
                  var root = new Node(data),
                          valued = +data.value && (root.value = data.value),
                          node,
                          nodes = [root],
                          child,
                          childs,
                          i,
                          n;
  
                  if (children == null)
                      children = defaultChildren;
  
                  while (node = nodes.pop()) {
                      if (valued)
                          node.value = +node.data.value;
                      if ((childs = children(node.data)) && (n = childs.length)) {
                          node.children = new Array(n);
                          for (i = n - 1; i >= 0; --i) {
                              nodes.push(child = node.children[i] = new Node(childs[i]));
                              child.parent = node;
                              child.depth = node.depth + 1;
                          }
                      }
                  }
  
                  return root.eachBefore(computeHeight);
              }
  
              function node_copy() {
                  return hierarchy(this).eachBefore(copyData);
              }
  
              function defaultChildren(d) {
                  return d.children;
              }
  
              function copyData(node) {
                  node.data = node.data.data;
              }
  
              function computeHeight(node) {
                  var height = 0;
                  do
                      node.height = height;
                  while ((node = node.parent) && (node.height < ++height));
              }
  
              function Node(data) {
                  this.data = data;
                  this.depth =
                          this.height = 0;
                  this.parent = null;
              }
  
              Node.prototype = hierarchy.prototype = {
                  constructor: Node,
                  count: node_count,
                  each: node_each,
                  eachAfter: node_eachAfter,
                  eachBefore: node_eachBefore,
                  sum: node_sum,
                  sort: node_sort,
                  path: node_path,
                  ancestors: node_ancestors,
                  descendants: node_descendants,
                  leaves: node_leaves,
                  links: node_links,
                  copy: node_copy
              };
  
              var slice$4 = Array.prototype.slice;
  
              function shuffle$1(array) {
                  var m = array.length,
                          t,
                          i;
  
                  while (m) {
                      i = Math.random() * m-- | 0;
                      t = array[m];
                      array[m] = array[i];
                      array[i] = t;
                  }
  
                  return array;
              }
  
              function enclose(circles) {
                  var i = 0, n = (circles = shuffle$1(slice$4.call(circles))).length, B = [], p, e;
  
                  while (i < n) {
                      p = circles[i];
                      if (e && enclosesWeak(e, p))
                          ++i;
                      else
                          e = encloseBasis(B = extendBasis(B, p)), i = 0;
                  }
  
                  return e;
              }
  
              function extendBasis(B, p) {
                  var i, j;
  
                  if (enclosesWeakAll(p, B))
                      return [p];
  
                  // If we get here then B must have at least one element.
                  for (i = 0; i < B.length; ++i) {
                      if (enclosesNot(p, B[i])
                              && enclosesWeakAll(encloseBasis2(B[i], p), B)) {
                          return [B[i], p];
                      }
                  }
  
                  // If we get here then B must have at least two elements.
                  for (i = 0; i < B.length - 1; ++i) {
                      for (j = i + 1; j < B.length; ++j) {
                          if (enclosesNot(encloseBasis2(B[i], B[j]), p)
                                  && enclosesNot(encloseBasis2(B[i], p), B[j])
                                  && enclosesNot(encloseBasis2(B[j], p), B[i])
                                  && enclosesWeakAll(encloseBasis3(B[i], B[j], p), B)) {
                              return [B[i], B[j], p];
                          }
                      }
                  }
  
                  // If we get here then something is very wrong.
                  throw new Error;
              }
  
              function enclosesNot(a, b) {
                  var dr = a.r - b.r, dx = b.x - a.x, dy = b.y - a.y;
                  return dr < 0 || dr * dr < dx * dx + dy * dy;
              }
  
              function enclosesWeak(a, b) {
                  var dr = a.r - b.r + 1e-6, dx = b.x - a.x, dy = b.y - a.y;
                  return dr > 0 && dr * dr > dx * dx + dy * dy;
              }
  
              function enclosesWeakAll(a, B) {
                  for (var i = 0; i < B.length; ++i) {
                      if (!enclosesWeak(a, B[i])) {
                          return false;
                      }
                  }
                  return true;
              }
  
              function encloseBasis(B) {
                  switch (B.length) {
                      case 1:
                          return encloseBasis1(B[0]);
                      case 2:
                          return encloseBasis2(B[0], B[1]);
                      case 3:
                          return encloseBasis3(B[0], B[1], B[2]);
                  }
              }
  
              function encloseBasis1(a) {
                  return {
                      x: a.x,
                      y: a.y,
                      r: a.r
                  };
              }
  
              function encloseBasis2(a, b) {
                  var x1 = a.x, y1 = a.y, r1 = a.r,
                          x2 = b.x, y2 = b.y, r2 = b.r,
                          x21 = x2 - x1, y21 = y2 - y1, r21 = r2 - r1,
                          l = Math.sqrt(x21 * x21 + y21 * y21);
                  return {
                      x: (x1 + x2 + x21 / l * r21) / 2,
                      y: (y1 + y2 + y21 / l * r21) / 2,
                      r: (l + r1 + r2) / 2
                  };
              }
  
              function encloseBasis3(a, b, c) {
                  var x1 = a.x, y1 = a.y, r1 = a.r,
                          x2 = b.x, y2 = b.y, r2 = b.r,
                          x3 = c.x, y3 = c.y, r3 = c.r,
                          a2 = x1 - x2,
                          a3 = x1 - x3,
                          b2 = y1 - y2,
                          b3 = y1 - y3,
                          c2 = r2 - r1,
                          c3 = r3 - r1,
                          d1 = x1 * x1 + y1 * y1 - r1 * r1,
                          d2 = d1 - x2 * x2 - y2 * y2 + r2 * r2,
                          d3 = d1 - x3 * x3 - y3 * y3 + r3 * r3,
                          ab = a3 * b2 - a2 * b3,
                          xa = (b2 * d3 - b3 * d2) / (ab * 2) - x1,
                          xb = (b3 * c2 - b2 * c3) / ab,
                          ya = (a3 * d2 - a2 * d3) / (ab * 2) - y1,
                          yb = (a2 * c3 - a3 * c2) / ab,
                          A = xb * xb + yb * yb - 1,
                          B = 2 * (r1 + xa * xb + ya * yb),
                          C = xa * xa + ya * ya - r1 * r1,
                          r = -(A ? (B + Math.sqrt(B * B - 4 * A * C)) / (2 * A) : C / B);
                  return {
                      x: x1 + xa + xb * r,
                      y: y1 + ya + yb * r,
                      r: r
                  };
              }
  
              function place(b, a, c) {
                  var dx = b.x - a.x, x, a2,
                          dy = b.y - a.y, y, b2,
                          d2 = dx * dx + dy * dy;
                  if (d2) {
                      a2 = a.r + c.r, a2 *= a2;
                      b2 = b.r + c.r, b2 *= b2;
                      if (a2 > b2) {
                          x = (d2 + b2 - a2) / (2 * d2);
                          y = Math.sqrt(Math.max(0, b2 / d2 - x * x));
                          c.x = b.x - x * dx - y * dy;
                          c.y = b.y - x * dy + y * dx;
                      } else {
                          x = (d2 + a2 - b2) / (2 * d2);
                          y = Math.sqrt(Math.max(0, a2 / d2 - x * x));
                          c.x = a.x + x * dx - y * dy;
                          c.y = a.y + x * dy + y * dx;
                      }
                  } else {
                      c.x = a.x + c.r;
                      c.y = a.y;
                  }
              }
  
              function intersects(a, b) {
                  var dr = a.r + b.r - 1e-6, dx = b.x - a.x, dy = b.y - a.y;
                  return dr > 0 && dr * dr > dx * dx + dy * dy;
              }
  
              function score(node) {
                  var a = node._,
                          b = node.next._,
                          ab = a.r + b.r,
                          dx = (a.x * b.r + b.x * a.r) / ab,
                          dy = (a.y * b.r + b.y * a.r) / ab;
                  return dx * dx + dy * dy;
              }
  
              function Node$1(circle) {
                  this._ = circle;
                  this.next = null;
                  this.previous = null;
              }
  
              function packEnclose(circles) {
                  if (!(n = circles.length))
                      return 0;
  
                  var a, b, c, n, aa, ca, i, j, k, sj, sk;
  
                  // Place the first circle.
                  a = circles[0], a.x = 0, a.y = 0;
                  if (!(n > 1))
                      return a.r;
  
                  // Place the second circle.
                  b = circles[1], a.x = -b.r, b.x = a.r, b.y = 0;
                  if (!(n > 2))
                      return a.r + b.r;
  
                  // Place the third circle.
                  place(b, a, c = circles[2]);
  
                  // Initialize the front-chain using the first three circles a, b and c.
                  a = new Node$1(a), b = new Node$1(b), c = new Node$1(c);
                  a.next = c.previous = b;
                  b.next = a.previous = c;
                  c.next = b.previous = a;
  
                  // Attempt to place each remaining circle…
                  pack: for (i = 3; i < n; ++i) {
                      place(a._, b._, c = circles[i]), c = new Node$1(c);
  
                      // Find the closest intersecting circle on the front-chain, if any.
                      // “Closeness” is determined by linear distance along the front-chain.
                      // “Ahead” or “behind” is likewise determined by linear distance.
                      j = b.next, k = a.previous, sj = b._.r, sk = a._.r;
                      do {
                          if (sj <= sk) {
                              if (intersects(j._, c._)) {
                                  b = j, a.next = b, b.previous = a, --i;
                                  continue pack;
                              }
                              sj += j._.r, j = j.next;
                          } else {
                              if (intersects(k._, c._)) {
                                  a = k, a.next = b, b.previous = a, --i;
                                  continue pack;
                              }
                              sk += k._.r, k = k.previous;
                          }
                      } while (j !== k.next);
  
                      // Success! Insert the new circle c between a and b.
                      c.previous = a, c.next = b, a.next = b.previous = b = c;
  
                      // Compute the new closest circle pair to the centroid.
                      aa = score(a);
                      while ((c = c.next) !== b) {
                          if ((ca = score(c)) < aa) {
                              a = c, aa = ca;
                          }
                      }
                      b = a.next;
                  }
  
                  // Compute the enclosing circle of the front chain.
                  a = [b._], c = b;
                  while ((c = c.next) !== b)
                      a.push(c._);
                  c = enclose(a);
  
                  // Translate the circles to put the enclosing circle around the origin.
                  for (i = 0; i < n; ++i)
                      a = circles[i], a.x -= c.x, a.y -= c.y;
  
                  return c.r;
              }
  
              function siblings(circles) {
                  packEnclose(circles);
                  return circles;
              }
  
              function optional(f) {
                  return f == null ? null : required(f);
              }
  
              function required(f) {
                  if (typeof f !== "function")
                      throw new Error;
                  return f;
              }
  
              function constantZero() {
                  return 0;
              }
  
              function constant$9(x) {
                  return function () {
                      return x;
                  };
              }
  
              function defaultRadius$1(d) {
                  return Math.sqrt(d.value);
              }
  
              function index$2() {
                  var radius = null,
                          dx = 1,
                          dy = 1,
                          padding = constantZero;
  
                  function pack(root) {
                      root.x = dx / 2, root.y = dy / 2;
                      if (radius) {
                          root.eachBefore(radiusLeaf(radius))
                                  .eachAfter(packChildren(padding, 0.5))
                                  .eachBefore(translateChild(1));
                      } else {
                          root.eachBefore(radiusLeaf(defaultRadius$1))
                                  .eachAfter(packChildren(constantZero, 1))
                                  .eachAfter(packChildren(padding, root.r / Math.min(dx, dy)))
                                  .eachBefore(translateChild(Math.min(dx, dy) / (2 * root.r)));
                      }
                      return root;
                  }
  
                  pack.radius = function (x) {
                      return arguments.length ? (radius = optional(x), pack) : radius;
                  };
  
                  pack.size = function (x) {
                      return arguments.length ? (dx = +x[0], dy = +x[1], pack) : [dx, dy];
                  };
  
                  pack.padding = function (x) {
                      return arguments.length ? (padding = typeof x === "function" ? x : constant$9(+x), pack) : padding;
                  };
  
                  return pack;
              }
  
              function radiusLeaf(radius) {
                  return function (node) {
                      if (!node.children) {
                          node.r = Math.max(0, +radius(node) || 0);
                      }
                  };
              }
  
              function packChildren(padding, k) {
                  return function (node) {
                      if (children = node.children) {
                          var children,
                                  i,
                                  n = children.length,
                                  r = padding(node) * k || 0,
                                  e;
  
                          if (r)
                              for (i = 0; i < n; ++i)
                                  children[i].r += r;
                          e = packEnclose(children);
                          if (r)
                              for (i = 0; i < n; ++i)
                                  children[i].r -= r;
                          node.r = e + r;
                      }
                  };
              }
  
              function translateChild(k) {
                  return function (node) {
                      var parent = node.parent;
                      node.r *= k;
                      if (parent) {
                          node.x = parent.x + k * node.x;
                          node.y = parent.y + k * node.y;
                      }
                  };
              }
  
              function roundNode(node) {
                  node.x0 = Math.round(node.x0);
                  node.y0 = Math.round(node.y0);
                  node.x1 = Math.round(node.x1);
                  node.y1 = Math.round(node.y1);
              }
  
              function treemapDice(parent, x0, y0, x1, y1) {
                  var nodes = parent.children,
                          node,
                          i = -1,
                          n = nodes.length,
                          k = parent.value && (x1 - x0) / parent.value;
  
                  while (++i < n) {
                      node = nodes[i], node.y0 = y0, node.y1 = y1;
                      node.x0 = x0, node.x1 = x0 += node.value * k;
                  }
              }
  
              function partition() {
                  var dx = 1,
                          dy = 1,
                          padding = 0,
                          round = false;
  
                  function partition(root) {
                      var n = root.height + 1;
                      root.x0 =
                              root.y0 = padding;
                      root.x1 = dx;
                      root.y1 = dy / n;
                      root.eachBefore(positionNode(dy, n));
                      if (round)
                          root.eachBefore(roundNode);
                      return root;
                  }
  
                  function positionNode(dy, n) {
                      return function (node) {
                          if (node.children) {
                              treemapDice(node, node.x0, dy * (node.depth + 1) / n, node.x1, dy * (node.depth + 2) / n);
                          }
                          var x0 = node.x0,
                                  y0 = node.y0,
                                  x1 = node.x1 - padding,
                                  y1 = node.y1 - padding;
                          if (x1 < x0)
                              x0 = x1 = (x0 + x1) / 2;
                          if (y1 < y0)
                              y0 = y1 = (y0 + y1) / 2;
                          node.x0 = x0;
                          node.y0 = y0;
                          node.x1 = x1;
                          node.y1 = y1;
                      };
                  }
  
                  partition.round = function (x) {
                      return arguments.length ? (round = !!x, partition) : round;
                  };
  
                  partition.size = function (x) {
                      return arguments.length ? (dx = +x[0], dy = +x[1], partition) : [dx, dy];
                  };
  
                  partition.padding = function (x) {
                      return arguments.length ? (padding = +x, partition) : padding;
                  };
  
                  return partition;
              }
  
              var keyPrefix$1 = "$", // Protect against keys like “__proto__”.
                      preroot = {depth: -1},
                      ambiguous = {};
  
              function defaultId(d) {
                  return d.id;
              }
  
              function defaultParentId(d) {
                  return d.parentId;
              }
  
              function stratify() {
                  var id = defaultId,
                          parentId = defaultParentId;
  
                  function stratify(data) {
                      var d,
                              i,
                              n = data.length,
                              root,
                              parent,
                              node,
                              nodes = new Array(n),
                              nodeId,
                              nodeKey,
                              nodeByKey = {};
  
                      for (i = 0; i < n; ++i) {
                          d = data[i], node = nodes[i] = new Node(d);
                          if ((nodeId = id(d, i, data)) != null && (nodeId += "")) {
                              nodeKey = keyPrefix$1 + (node.id = nodeId);
                              nodeByKey[nodeKey] = nodeKey in nodeByKey ? ambiguous : node;
                          }
                      }
  
                      for (i = 0; i < n; ++i) {
                          node = nodes[i], nodeId = parentId(data[i], i, data);
                          if (nodeId == null || !(nodeId += "")) {
                              if (root)
                                  throw new Error("multiple roots");
                              root = node;
                          } else {
                              parent = nodeByKey[keyPrefix$1 + nodeId];
                              if (!parent)
                                  throw new Error("missing: " + nodeId);
                              if (parent === ambiguous)
                                  throw new Error("ambiguous: " + nodeId);
                              if (parent.children)
                                  parent.children.push(node);
                              else
                                  parent.children = [node];
                              node.parent = parent;
                          }
                      }
  
                      if (!root)
                          throw new Error("no root");
                      root.parent = preroot;
                      root.eachBefore(function (node) {
                          node.depth = node.parent.depth + 1;
                          --n;
                      }).eachBefore(computeHeight);
                      root.parent = null;
                      if (n > 0)
                          throw new Error("cycle");
  
                      return root;
                  }
  
                  stratify.id = function (x) {
                      return arguments.length ? (id = required(x), stratify) : id;
                  };
  
                  stratify.parentId = function (x) {
                      return arguments.length ? (parentId = required(x), stratify) : parentId;
                  };
  
                  return stratify;
              }
  
              function defaultSeparation$1(a, b) {
                  return a.parent === b.parent ? 1 : 2;
              }
  
  // function radialSeparation(a, b) {
  //   return (a.parent === b.parent ? 1 : 2) / a.depth;
  // }
  
  // This function is used to traverse the left contour of a subtree (or
  // subforest). It returns the successor of v on this contour. This successor is
  // either given by the leftmost child of v or by the thread of v. The function
  // returns null if and only if v is on the highest level of its subtree.
              function nextLeft(v) {
                  var children = v.children;
                  return children ? children[0] : v.t;
              }
  
  // This function works analogously to nextLeft.
              function nextRight(v) {
                  var children = v.children;
                  return children ? children[children.length - 1] : v.t;
              }
  
  // Shifts the current subtree rooted at w+. This is done by increasing
  // prelim(w+) and mod(w+) by shift.
              function moveSubtree(wm, wp, shift) {
                  var change = shift / (wp.i - wm.i);
                  wp.c -= change;
                  wp.s += shift;
                  wm.c += change;
                  wp.z += shift;
                  wp.m += shift;
              }
  
  // All other shifts, applied to the smaller subtrees between w- and w+, are
  // performed by this function. To prepare the shifts, we have to adjust
  // change(w+), shift(w+), and change(w-).
              function executeShifts(v) {
                  var shift = 0,
                          change = 0,
                          children = v.children,
                          i = children.length,
                          w;
                  while (--i >= 0) {
                      w = children[i];
                      w.z += shift;
                      w.m += shift;
                      shift += w.s + (change += w.c);
                  }
              }
  
  // If vi-’s ancestor is a sibling of v, returns vi-’s ancestor. Otherwise,
  // returns the specified (default) ancestor.
              function nextAncestor(vim, v, ancestor) {
                  return vim.a.parent === v.parent ? vim.a : ancestor;
              }
  
              function TreeNode(node, i) {
                  this._ = node;
                  this.parent = null;
                  this.children = null;
                  this.A = null; // default ancestor
                  this.a = this; // ancestor
                  this.z = 0; // prelim
                  this.m = 0; // mod
                  this.c = 0; // change
                  this.s = 0; // shift
                  this.t = null; // thread
                  this.i = i; // number
              }
  
              TreeNode.prototype = Object.create(Node.prototype);
  
              function treeRoot(root) {
                  var tree = new TreeNode(root, 0),
                          node,
                          nodes = [tree],
                          child,
                          children,
                          i,
                          n;
  
                  while (node = nodes.pop()) {
                      if (children = node._.children) {
                          node.children = new Array(n = children.length);
                          for (i = n - 1; i >= 0; --i) {
                              nodes.push(child = node.children[i] = new TreeNode(children[i], i));
                              child.parent = node;
                          }
                      }
                  }
  
                  (tree.parent = new TreeNode(null, 0)).children = [tree];
                  return tree;
              }
  
  // Node-link tree diagram using the Reingold-Tilford "tidy" algorithm
              function tree() {
                  var separation = defaultSeparation$1,
                          dx = 1,
                          dy = 1,
                          nodeSize = null;
  
                  function tree(root) {
                      var t = treeRoot(root);
  
                      // Compute the layout using Buchheim et al.’s algorithm.
                      t.eachAfter(firstWalk), t.parent.m = -t.z;
                      t.eachBefore(secondWalk);
  
                      // If a fixed node size is specified, scale x and y.
                      if (nodeSize)
                          root.eachBefore(sizeNode);
  
                      // If a fixed tree size is specified, scale x and y based on the extent.
                      // Compute the left-most, right-most, and depth-most nodes for extents.
                      else {
                          var left = root,
                                  right = root,
                                  bottom = root;
                          root.eachBefore(function (node) {
                              if (node.x < left.x)
                                  left = node;
                              if (node.x > right.x)
                                  right = node;
                              if (node.depth > bottom.depth)
                                  bottom = node;
                          });
                          var s = left === right ? 1 : separation(left, right) / 2,
                                  tx = s - left.x,
                                  kx = dx / (right.x + s + tx),
                                  ky = dy / (bottom.depth || 1);
                          root.eachBefore(function (node) {
                              node.x = (node.x + tx) * kx;
                              node.y = node.depth * ky;
                          });
                      }
  
                      return root;
                  }
  
                  // Computes a preliminary x-coordinate for v. Before that, FIRST WALK is
                  // applied recursively to the children of v, as well as the function
                  // APPORTION. After spacing out the children by calling EXECUTE SHIFTS, the
                  // node v is placed to the midpoint of its outermost children.
                  function firstWalk(v) {
                      var children = v.children,
                              siblings = v.parent.children,
                              w = v.i ? siblings[v.i - 1] : null;
                      if (children) {
                          executeShifts(v);
                          var midpoint = (children[0].z + children[children.length - 1].z) / 2;
                          if (w) {
                              v.z = w.z + separation(v._, w._);
                              v.m = v.z - midpoint;
                          } else {
                              v.z = midpoint;
                          }
                      } else if (w) {
                          v.z = w.z + separation(v._, w._);
                      }
                      v.parent.A = apportion(v, w, v.parent.A || siblings[0]);
                  }
  
                  // Computes all real x-coordinates by summing up the modifiers recursively.
                  function secondWalk(v) {
                      v._.x = v.z + v.parent.m;
                      v.m += v.parent.m;
                  }
  
                  // The core of the algorithm. Here, a new subtree is combined with the
                  // previous subtrees. Threads are used to traverse the inside and outside
                  // contours of the left and right subtree up to the highest common level. The
                  // vertices used for the traversals are vi+, vi-, vo-, and vo+, where the
                  // superscript o means outside and i means inside, the subscript - means left
                  // subtree and + means right subtree. For summing up the modifiers along the
                  // contour, we use respective variables si+, si-, so-, and so+. Whenever two
                  // nodes of the inside contours conflict, we compute the left one of the
                  // greatest uncommon ancestors using the function ANCESTOR and call MOVE
                  // SUBTREE to shift the subtree and prepare the shifts of smaller subtrees.
                  // Finally, we add a new thread (if necessary).
                  function apportion(v, w, ancestor) {
                      if (w) {
                          var vip = v,
                                  vop = v,
                                  vim = w,
                                  vom = vip.parent.children[0],
                                  sip = vip.m,
                                  sop = vop.m,
                                  sim = vim.m,
                                  som = vom.m,
                                  shift;
                          while (vim = nextRight(vim), vip = nextLeft(vip), vim && vip) {
                              vom = nextLeft(vom);
                              vop = nextRight(vop);
                              vop.a = v;
                              shift = vim.z + sim - vip.z - sip + separation(vim._, vip._);
                              if (shift > 0) {
                                  moveSubtree(nextAncestor(vim, v, ancestor), v, shift);
                                  sip += shift;
                                  sop += shift;
                              }
                              sim += vim.m;
                              sip += vip.m;
                              som += vom.m;
                              sop += vop.m;
                          }
                          if (vim && !nextRight(vop)) {
                              vop.t = vim;
                              vop.m += sim - sop;
                          }
                          if (vip && !nextLeft(vom)) {
                              vom.t = vip;
                              vom.m += sip - som;
                              ancestor = v;
                          }
                      }
                      return ancestor;
                  }
  
                  function sizeNode(node) {
                      node.x *= dx;
                      node.y = node.depth * dy;
                  }
  
                  tree.separation = function (x) {
                      return arguments.length ? (separation = x, tree) : separation;
                  };
  
                  tree.size = function (x) {
                      return arguments.length ? (nodeSize = false, dx = +x[0], dy = +x[1], tree) : (nodeSize ? null : [dx, dy]);
                  };
  
                  tree.nodeSize = function (x) {
                      return arguments.length ? (nodeSize = true, dx = +x[0], dy = +x[1], tree) : (nodeSize ? [dx, dy] : null);
                  };
  
                  return tree;
              }
  
              function treemapSlice(parent, x0, y0, x1, y1) {
                  var nodes = parent.children,
                          node,
                          i = -1,
                          n = nodes.length,
                          k = parent.value && (y1 - y0) / parent.value;
  
                  while (++i < n) {
                      node = nodes[i], node.x0 = x0, node.x1 = x1;
                      node.y0 = y0, node.y1 = y0 += node.value * k;
                  }
              }
  
              var phi = (1 + Math.sqrt(5)) / 2;
  
              function squarifyRatio(ratio, parent, x0, y0, x1, y1) {
                  var rows = [],
                          nodes = parent.children,
                          row,
                          nodeValue,
                          i0 = 0,
                          i1 = 0,
                          n = nodes.length,
                          dx, dy,
                          value = parent.value,
                          sumValue,
                          minValue,
                          maxValue,
                          newRatio,
                          minRatio,
                          alpha,
                          beta;
  
                  while (i0 < n) {
                      dx = x1 - x0, dy = y1 - y0;
  
                      // Find the next non-empty node.
                      do
                          sumValue = nodes[i1++].value;
                      while (!sumValue && i1 < n);
                      minValue = maxValue = sumValue;
                      alpha = Math.max(dy / dx, dx / dy) / (value * ratio);
                      beta = sumValue * sumValue * alpha;
                      minRatio = Math.max(maxValue / beta, beta / minValue);
  
                      // Keep adding nodes while the aspect ratio maintains or improves.
                      for (; i1 < n; ++i1) {
                          sumValue += nodeValue = nodes[i1].value;
                          if (nodeValue < minValue)
                              minValue = nodeValue;
                          if (nodeValue > maxValue)
                              maxValue = nodeValue;
                          beta = sumValue * sumValue * alpha;
                          newRatio = Math.max(maxValue / beta, beta / minValue);
                          if (newRatio > minRatio) {
                              sumValue -= nodeValue;
                              break;
                          }
                          minRatio = newRatio;
                      }
  
                      // Position and record the row orientation.
                      rows.push(row = {value: sumValue, dice: dx < dy, children: nodes.slice(i0, i1)});
                      if (row.dice)
                          treemapDice(row, x0, y0, x1, value ? y0 += dy * sumValue / value : y1);
                      else
                          treemapSlice(row, x0, y0, value ? x0 += dx * sumValue / value : x1, y1);
                      value -= sumValue, i0 = i1;
                  }
  
                  return rows;
              }
  
              var squarify = (function custom(ratio) {
  
                  function squarify(parent, x0, y0, x1, y1) {
                      squarifyRatio(ratio, parent, x0, y0, x1, y1);
                  }
  
                  squarify.ratio = function (x) {
                      return custom((x = +x) > 1 ? x : 1);
                  };
  
                  return squarify;
              })(phi);
  
              function index$3() {
                  var tile = squarify,
                          round = false,
                          dx = 1,
                          dy = 1,
                          paddingStack = [0],
                          paddingInner = constantZero,
                          paddingTop = constantZero,
                          paddingRight = constantZero,
                          paddingBottom = constantZero,
                          paddingLeft = constantZero;
  
                  function treemap(root) {
                      root.x0 =
                              root.y0 = 0;
                      root.x1 = dx;
                      root.y1 = dy;
                      root.eachBefore(positionNode);
                      paddingStack = [0];
                      if (round)
                          root.eachBefore(roundNode);
                      return root;
                  }
  
                  function positionNode(node) {
                      var p = paddingStack[node.depth],
                              x0 = node.x0 + p,
                              y0 = node.y0 + p,
                              x1 = node.x1 - p,
                              y1 = node.y1 - p;
                      if (x1 < x0)
                          x0 = x1 = (x0 + x1) / 2;
                      if (y1 < y0)
                          y0 = y1 = (y0 + y1) / 2;
                      node.x0 = x0;
                      node.y0 = y0;
                      node.x1 = x1;
                      node.y1 = y1;
                      if (node.children) {
                          p = paddingStack[node.depth + 1] = paddingInner(node) / 2;
                          x0 += paddingLeft(node) - p;
                          y0 += paddingTop(node) - p;
                          x1 -= paddingRight(node) - p;
                          y1 -= paddingBottom(node) - p;
                          if (x1 < x0)
                              x0 = x1 = (x0 + x1) / 2;
                          if (y1 < y0)
                              y0 = y1 = (y0 + y1) / 2;
                          tile(node, x0, y0, x1, y1);
                      }
                  }
  
                  treemap.round = function (x) {
                      return arguments.length ? (round = !!x, treemap) : round;
                  };
  
                  treemap.size = function (x) {
                      return arguments.length ? (dx = +x[0], dy = +x[1], treemap) : [dx, dy];
                  };
  
                  treemap.tile = function (x) {
                      return arguments.length ? (tile = required(x), treemap) : tile;
                  };
  
                  treemap.padding = function (x) {
                      return arguments.length ? treemap.paddingInner(x).paddingOuter(x) : treemap.paddingInner();
                  };
  
                  treemap.paddingInner = function (x) {
                      return arguments.length ? (paddingInner = typeof x === "function" ? x : constant$9(+x), treemap) : paddingInner;
                  };
  
                  treemap.paddingOuter = function (x) {
                      return arguments.length ? treemap.paddingTop(x).paddingRight(x).paddingBottom(x).paddingLeft(x) : treemap.paddingTop();
                  };
  
                  treemap.paddingTop = function (x) {
                      return arguments.length ? (paddingTop = typeof x === "function" ? x : constant$9(+x), treemap) : paddingTop;
                  };
  
                  treemap.paddingRight = function (x) {
                      return arguments.length ? (paddingRight = typeof x === "function" ? x : constant$9(+x), treemap) : paddingRight;
                  };
  
                  treemap.paddingBottom = function (x) {
                      return arguments.length ? (paddingBottom = typeof x === "function" ? x : constant$9(+x), treemap) : paddingBottom;
                  };
  
                  treemap.paddingLeft = function (x) {
                      return arguments.length ? (paddingLeft = typeof x === "function" ? x : constant$9(+x), treemap) : paddingLeft;
                  };
  
                  return treemap;
              }
  
              function binary(parent, x0, y0, x1, y1) {
                  var nodes = parent.children,
                          i, n = nodes.length,
                          sum, sums = new Array(n + 1);
  
                  for (sums[0] = sum = i = 0; i < n; ++i) {
                      sums[i + 1] = sum += nodes[i].value;
                  }
  
                  partition(0, n, parent.value, x0, y0, x1, y1);
  
                  function partition(i, j, value, x0, y0, x1, y1) {
                      if (i >= j - 1) {
                          var node = nodes[i];
                          node.x0 = x0, node.y0 = y0;
                          node.x1 = x1, node.y1 = y1;
                          return;
                      }
  
                      var valueOffset = sums[i],
                              valueTarget = (value / 2) + valueOffset,
                              k = i + 1,
                              hi = j - 1;
  
                      while (k < hi) {
                          var mid = k + hi >>> 1;
                          if (sums[mid] < valueTarget)
                              k = mid + 1;
                          else
                              hi = mid;
                      }
  
                      if ((valueTarget - sums[k - 1]) < (sums[k] - valueTarget) && i + 1 < k)
                          --k;
  
                      var valueLeft = sums[k] - valueOffset,
                              valueRight = value - valueLeft;
  
                      if ((x1 - x0) > (y1 - y0)) {
                          var xk = (x0 * valueRight + x1 * valueLeft) / value;
                          partition(i, k, valueLeft, x0, y0, xk, y1);
                          partition(k, j, valueRight, xk, y0, x1, y1);
                      } else {
                          var yk = (y0 * valueRight + y1 * valueLeft) / value;
                          partition(i, k, valueLeft, x0, y0, x1, yk);
                          partition(k, j, valueRight, x0, yk, x1, y1);
                      }
                  }
              }
  
              function sliceDice(parent, x0, y0, x1, y1) {
                  (parent.depth & 1 ? treemapSlice : treemapDice)(parent, x0, y0, x1, y1);
              }
  
              var resquarify = (function custom(ratio) {
  
                  function resquarify(parent, x0, y0, x1, y1) {
                      if ((rows = parent._squarify) && (rows.ratio === ratio)) {
                          var rows,
                                  row,
                                  nodes,
                                  i,
                                  j = -1,
                                  n,
                                  m = rows.length,
                                  value = parent.value;
  
                          while (++j < m) {
                              row = rows[j], nodes = row.children;
                              for (i = row.value = 0, n = nodes.length; i < n; ++i)
                                  row.value += nodes[i].value;
                              if (row.dice)
                                  treemapDice(row, x0, y0, x1, y0 += (y1 - y0) * row.value / value);
                              else
                                  treemapSlice(row, x0, y0, x0 += (x1 - x0) * row.value / value, y1);
                              value -= row.value;
                          }
                      } else {
                          parent._squarify = rows = squarifyRatio(ratio, parent, x0, y0, x1, y1);
                          rows.ratio = ratio;
                      }
                  }
  
                  resquarify.ratio = function (x) {
                      return custom((x = +x) > 1 ? x : 1);
                  };
  
                  return resquarify;
              })(phi);
  
              function area$2(polygon) {
                  var i = -1,
                          n = polygon.length,
                          a,
                          b = polygon[n - 1],
                          area = 0;
  
                  while (++i < n) {
                      a = b;
                      b = polygon[i];
                      area += a[1] * b[0] - a[0] * b[1];
                  }
  
                  return area / 2;
              }
  
              function centroid$1(polygon) {
                  var i = -1,
                          n = polygon.length,
                          x = 0,
                          y = 0,
                          a,
                          b = polygon[n - 1],
                          c,
                          k = 0;
  
                  while (++i < n) {
                      a = b;
                      b = polygon[i];
                      k += c = a[0] * b[1] - b[0] * a[1];
                      x += (a[0] + b[0]) * c;
                      y += (a[1] + b[1]) * c;
                  }
  
                  return k *= 3, [x / k, y / k];
              }
  
  // Returns the 2D cross product of AB and AC vectors, i.e., the z-component of
  // the 3D cross product in a quadrant I Cartesian coordinate system (+x is
  // right, +y is up). Returns a positive value if ABC is counter-clockwise,
  // negative if clockwise, and zero if the points are collinear.
              function cross$1(a, b, c) {
                  return (b[0] - a[0]) * (c[1] - a[1]) - (b[1] - a[1]) * (c[0] - a[0]);
              }
  
              function lexicographicOrder(a, b) {
                  return a[0] - b[0] || a[1] - b[1];
              }
  
  // Computes the upper convex hull per the monotone chain algorithm.
  // Assumes points.length >= 3, is sorted by x, unique in y.
  // Returns an array of indices into points in left-to-right order.
              function computeUpperHullIndexes(points) {
                  var n = points.length,
                          indexes = [0, 1],
                          size = 2;
  
                  for (var i = 2; i < n; ++i) {
                      while (size > 1 && cross$1(points[indexes[size - 2]], points[indexes[size - 1]], points[i]) <= 0)
                          --size;
                      indexes[size++] = i;
                  }
  
                  return indexes.slice(0, size); // remove popped points
              }
  
              function hull(points) {
                  if ((n = points.length) < 3)
                      return null;
  
                  var i,
                          n,
                          sortedPoints = new Array(n),
                          flippedPoints = new Array(n);
  
                  for (i = 0; i < n; ++i)
                      sortedPoints[i] = [+points[i][0], +points[i][1], i];
                  sortedPoints.sort(lexicographicOrder);
                  for (i = 0; i < n; ++i)
                      flippedPoints[i] = [sortedPoints[i][0], -sortedPoints[i][1]];
  
                  var upperIndexes = computeUpperHullIndexes(sortedPoints),
                          lowerIndexes = computeUpperHullIndexes(flippedPoints);
  
                  // Construct the hull polygon, removing possible duplicate endpoints.
                  var skipLeft = lowerIndexes[0] === upperIndexes[0],
                          skipRight = lowerIndexes[lowerIndexes.length - 1] === upperIndexes[upperIndexes.length - 1],
                          hull = [];
  
                  // Add upper hull in right-to-l order.
                  // Then add lower hull in left-to-right order.
                  for (i = upperIndexes.length - 1; i >= 0; --i)
                      hull.push(points[sortedPoints[upperIndexes[i]][2]]);
                  for (i = + skipLeft; i < lowerIndexes.length - skipRight; ++i)
                      hull.push(points[sortedPoints[lowerIndexes[i]][2]]);
  
                  return hull;
              }
  
              function contains$2(polygon, point) {
                  var n = polygon.length,
                          p = polygon[n - 1],
                          x = point[0], y = point[1],
                          x0 = p[0], y0 = p[1],
                          x1, y1,
                          inside = false;
  
                  for (var i = 0; i < n; ++i) {
                      p = polygon[i], x1 = p[0], y1 = p[1];
                      if (((y1 > y) !== (y0 > y)) && (x < (x0 - x1) * (y - y1) / (y0 - y1) + x1))
                          inside = !inside;
                      x0 = x1, y0 = y1;
                  }
  
                  return inside;
              }
  
              function length$2(polygon) {
                  var i = -1,
                          n = polygon.length,
                          b = polygon[n - 1],
                          xa,
                          ya,
                          xb = b[0],
                          yb = b[1],
                          perimeter = 0;
  
                  while (++i < n) {
                      xa = xb;
                      ya = yb;
                      b = polygon[i];
                      xb = b[0];
                      yb = b[1];
                      xa -= xb;
                      ya -= yb;
                      perimeter += Math.sqrt(xa * xa + ya * ya);
                  }
  
                  return perimeter;
              }
  
              function defaultSource$1() {
                  return Math.random();
              }
  
              var uniform = (function sourceRandomUniform(source) {
                  function randomUniform(min, max) {
                      min = min == null ? 0 : +min;
                      max = max == null ? 1 : +max;
                      if (arguments.length === 1)
                          max = min, min = 0;
                      else
                          max -= min;
                      return function () {
                          return source() * max + min;
                      };
                  }
  
                  randomUniform.source = sourceRandomUniform;
  
                  return randomUniform;
              })(defaultSource$1);
  
              var normal = (function sourceRandomNormal(source) {
                  function randomNormal(mu, sigma) {
                      var x, r;
                      mu = mu == null ? 0 : +mu;
                      sigma = sigma == null ? 1 : +sigma;
                      return function () {
                          var y;
  
                          // If available, use the second previously-generated uniform random.
                          if (x != null)
                              y = x, x = null;
  
                          // Otherwise, generate a new x and y.
                          else
                              do {
                                  x = source() * 2 - 1;
                                  y = source() * 2 - 1;
                                  r = x * x + y * y;
                              } while (!r || r > 1);
  
                          return mu + sigma * y * Math.sqrt(-2 * Math.log(r) / r);
                      };
                  }
  
                  randomNormal.source = sourceRandomNormal;
  
                  return randomNormal;
              })(defaultSource$1);
  
              var logNormal = (function sourceRandomLogNormal(source) {
                  function randomLogNormal() {
                      var randomNormal = normal.source(source).apply(this, arguments);
                      return function () {
                          return Math.exp(randomNormal());
                      };
                  }
  
                  randomLogNormal.source = sourceRandomLogNormal;
  
                  return randomLogNormal;
              })(defaultSource$1);
  
              var irwinHall = (function sourceRandomIrwinHall(source) {
                  function randomIrwinHall(n) {
                      return function () {
                          for (var sum = 0, i = 0; i < n; ++i)
                              sum += source();
                          return sum;
                      };
                  }
  
                  randomIrwinHall.source = sourceRandomIrwinHall;
  
                  return randomIrwinHall;
              })(defaultSource$1);
  
              var bates = (function sourceRandomBates(source) {
                  function randomBates(n) {
                      var randomIrwinHall = irwinHall.source(source)(n);
                      return function () {
                          return randomIrwinHall() / n;
                      };
                  }
  
                  randomBates.source = sourceRandomBates;
  
                  return randomBates;
              })(defaultSource$1);
  
              var exponential$1 = (function sourceRandomExponential(source) {
                  function randomExponential(lambda) {
                      return function () {
                          return -Math.log(1 - source()) / lambda;
                      };
                  }
  
                  randomExponential.source = sourceRandomExponential;
  
                  return randomExponential;
              })(defaultSource$1);
  
              function initRange(domain, range) {
                  switch (arguments.length) {
                      case 0:
                          break;
                      case 1:
                          this.range(domain);
                          break;
                      default:
                          this.range(range).domain(domain);
                          break;
                  }
                  return this;
              }
  
              function initInterpolator(domain, interpolator) {
                  switch (arguments.length) {
                      case 0:
                          break;
                      case 1:
                          this.interpolator(domain);
                          break;
                      default:
                          this.interpolator(interpolator).domain(domain);
                          break;
                  }
                  return this;
              }
  
              var array$3 = Array.prototype;
  
              var map$3 = array$3.map;
              var slice$5 = array$3.slice;
  
              var implicit = {name: "implicit"};
  
              function ordinal() {
                  var index = map$1(),
                          domain = [],
                          range = [],
                          unknown = implicit;
  
                  function scale(d) {
                      var key = d + "", i = index.get(key);
                      if (!i) {
                          if (unknown !== implicit)
                              return unknown;
                          index.set(key, i = domain.push(d));
                      }
                      return range[(i - 1) % range.length];
                  }
  
                  scale.domain = function (_) {
                      if (!arguments.length)
                          return domain.slice();
                      domain = [], index = map$1();
                      var i = -1, n = _.length, d, key;
                      while (++i < n)
                          if (!index.has(key = (d = _[i]) + ""))
                              index.set(key, domain.push(d));
                      return scale;
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (range = slice$5.call(_), scale) : range.slice();
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  scale.copy = function () {
                      return ordinal(domain, range).unknown(unknown);
                  };
  
                  initRange.apply(scale, arguments);
  
                  return scale;
              }
  
              function band() {
                  var scale = ordinal().unknown(undefined),
                          domain = scale.domain,
                          ordinalRange = scale.range,
                          range = [0, 1],
                          step,
                          bandwidth,
                          round = false,
                          paddingInner = 0,
                          paddingOuter = 0,
                          align = 0.5;
  
                  delete scale.unknown;
  
                  function rescale() {
                      var n = domain().length,
                              reverse = range[1] < range[0],
                              start = range[reverse - 0],
                              stop = range[1 - reverse];
                      step = (stop - start) / Math.max(1, n - paddingInner + paddingOuter * 2);
                      if (round)
                          step = Math.floor(step);
                      start += (stop - start - step * (n - paddingInner)) * align;
                      bandwidth = step * (1 - paddingInner);
                      if (round)
                          start = Math.round(start), bandwidth = Math.round(bandwidth);
                      var values = sequence(n).map(function (i) {
                          return start + step * i;
                      });
                      return ordinalRange(reverse ? values.reverse() : values);
                  }
  
                  scale.domain = function (_) {
                      return arguments.length ? (domain(_), rescale()) : domain();
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (range = [+_[0], +_[1]], rescale()) : range.slice();
                  };
  
                  scale.rangeRound = function (_) {
                      return range = [+_[0], +_[1]], round = true, rescale();
                  };
  
                  scale.bandwidth = function () {
                      return bandwidth;
                  };
  
                  scale.step = function () {
                      return step;
                  };
  
                  scale.round = function (_) {
                      return arguments.length ? (round = !!_, rescale()) : round;
                  };
  
                  scale.padding = function (_) {
                      return arguments.length ? (paddingInner = Math.min(1, paddingOuter = +_), rescale()) : paddingInner;
                  };
  
                  scale.paddingInner = function (_) {
                      return arguments.length ? (paddingInner = Math.min(1, _), rescale()) : paddingInner;
                  };
  
                  scale.paddingOuter = function (_) {
                      return arguments.length ? (paddingOuter = +_, rescale()) : paddingOuter;
                  };
  
                  scale.align = function (_) {
                      return arguments.length ? (align = Math.max(0, Math.min(1, _)), rescale()) : align;
                  };
  
                  scale.copy = function () {
                      return band(domain(), range)
                              .round(round)
                              .paddingInner(paddingInner)
                              .paddingOuter(paddingOuter)
                              .align(align);
                  };
  
                  return initRange.apply(rescale(), arguments);
              }
  
              function pointish(scale) {
                  var copy = scale.copy;
  
                  scale.padding = scale.paddingOuter;
                  delete scale.paddingInner;
                  delete scale.paddingOuter;
  
                  scale.copy = function () {
                      return pointish(copy());
                  };
  
                  return scale;
              }
  
              function point$1() {
                  return pointish(band.apply(null, arguments).paddingInner(1));
              }
  
              function constant$a(x) {
                  return function () {
                      return x;
                  };
              }
  
              function number$2(x) {
                  return +x;
              }
  
              var unit = [0, 1];
  
              function identity$6(x) {
                  return x;
              }
  
              function normalize(a, b) {
                  return (b -= (a = +a))
                          ? function (x) {
                              return (x - a) / b;
                          }
                  : constant$a(isNaN(b) ? NaN : 0.5);
              }
  
              function clamper(domain) {
                  var a = domain[0], b = domain[domain.length - 1], t;
                  if (a > b)
                      t = a, a = b, b = t;
                  return function (x) {
                      return Math.max(a, Math.min(b, x));
                  };
              }
  
  // normalize(a, b)(x) takes a domain value x in [a,b] and returns the corresponding parameter t in [0,1].
  // interpolate(a, b)(t) takes a parameter t in [0,1] and returns the corresponding range value x in [a,b].
              function bimap(domain, range, interpolate) {
                  var d0 = domain[0], d1 = domain[1], r0 = range[0], r1 = range[1];
                  if (d1 < d0)
                      d0 = normalize(d1, d0), r0 = interpolate(r1, r0);
                  else
                      d0 = normalize(d0, d1), r0 = interpolate(r0, r1);
                  return function (x) {
                      return r0(d0(x));
                  };
              }
  
              function polymap(domain, range, interpolate) {
                  var j = Math.min(domain.length, range.length) - 1,
                          d = new Array(j),
                          r = new Array(j),
                          i = -1;
  
                  // Reverse descending domains.
                  if (domain[j] < domain[0]) {
                      domain = domain.slice().reverse();
                      range = range.slice().reverse();
                  }
  
                  while (++i < j) {
                      d[i] = normalize(domain[i], domain[i + 1]);
                      r[i] = interpolate(range[i], range[i + 1]);
                  }
  
                  return function (x) {
                      var i = bisectRight(domain, x, 1, j) - 1;
                      return r[i](d[i](x));
                  };
              }
  
              function copy(source, target) {
                  return target
                          .domain(source.domain())
                          .range(source.range())
                          .interpolate(source.interpolate())
                          .clamp(source.clamp())
                          .unknown(source.unknown());
              }
  
              function transformer$1() {
                  var domain = unit,
                          range = unit,
                          interpolate = interpolateValue,
                          transform,
                          untransform,
                          unknown,
                          clamp = identity$6,
                          piecewise,
                          output,
                          input;
  
                  function rescale() {
                      piecewise = Math.min(domain.length, range.length) > 2 ? polymap : bimap;
                      output = input = null;
                      return scale;
                  }
  
                  function scale(x) {
                      return isNaN(x = +x) ? unknown : (output || (output = piecewise(domain.map(transform), range, interpolate)))(transform(clamp(x)));
                  }
  
                  scale.invert = function (y) {
                      return clamp(untransform((input || (input = piecewise(range, domain.map(transform), interpolateNumber)))(y)));
                  };
  
                  scale.domain = function (_) {
                      return arguments.length ? (domain = map$3.call(_, number$2), clamp === identity$6 || (clamp = clamper(domain)), rescale()) : domain.slice();
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (range = slice$5.call(_), rescale()) : range.slice();
                  };
  
                  scale.rangeRound = function (_) {
                      return range = slice$5.call(_), interpolate = interpolateRound, rescale();
                  };
  
                  scale.clamp = function (_) {
                      return arguments.length ? (clamp = _ ? clamper(domain) : identity$6, scale) : clamp !== identity$6;
                  };
  
                  scale.interpolate = function (_) {
                      return arguments.length ? (interpolate = _, rescale()) : interpolate;
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  return function (t, u) {
                      transform = t, untransform = u;
                      return rescale();
                  };
              }
  
              function continuous(transform, untransform) {
                  return transformer$1()(transform, untransform);
              }
  
              function tickFormat(start, stop, count, specifier) {
                  var step = tickStep(start, stop, count),
                          precision;
                  specifier = formatSpecifier(specifier == null ? ",f" : specifier);
                  switch (specifier.type) {
                      case "s":
                      {
                          var value = Math.max(Math.abs(start), Math.abs(stop));
                          if (specifier.precision == null && !isNaN(precision = precisionPrefix(step, value)))
                              specifier.precision = precision;
                          return exports.formatPrefix(specifier, value);
                      }
                      case "":
                      case "e":
                      case "g":
                      case "p":
                      case "r":
                      {
                          if (specifier.precision == null && !isNaN(precision = precisionRound(step, Math.max(Math.abs(start), Math.abs(stop)))))
                              specifier.precision = precision - (specifier.type === "e");
                          break;
                      }
                      case "f":
                      case "%":
                      {
                          if (specifier.precision == null && !isNaN(precision = precisionFixed(step)))
                              specifier.precision = precision - (specifier.type === "%") * 2;
                          break;
                      }
                  }
                  return exports.format(specifier);
              }
  
              function linearish(scale) {
                  var domain = scale.domain;
  
                  scale.ticks = function (count) {
                      var d = domain();
                      return ticks(d[0], d[d.length - 1], count == null ? 10 : count);
                  };
  
                  scale.tickFormat = function (count, specifier) {
                      var d = domain();
                      return tickFormat(d[0], d[d.length - 1], count == null ? 10 : count, specifier);
                  };
  
                  scale.nice = function (count) {
                      if (count == null)
                          count = 10;
  
                      var d = domain(),
                              i0 = 0,
                              i1 = d.length - 1,
                              start = d[i0],
                              stop = d[i1],
                              step;
  
                      if (stop < start) {
                          step = start, start = stop, stop = step;
                          step = i0, i0 = i1, i1 = step;
                      }
  
                      step = tickIncrement(start, stop, count);
  
                      if (step > 0) {
                          start = Math.floor(start / step) * step;
                          stop = Math.ceil(stop / step) * step;
                          step = tickIncrement(start, stop, count);
                      } else if (step < 0) {
                          start = Math.ceil(start * step) / step;
                          stop = Math.floor(stop * step) / step;
                          step = tickIncrement(start, stop, count);
                      }
  
                      if (step > 0) {
                          d[i0] = Math.floor(start / step) * step;
                          d[i1] = Math.ceil(stop / step) * step;
                          domain(d);
                      } else if (step < 0) {
                          d[i0] = Math.ceil(start * step) / step;
                          d[i1] = Math.floor(stop * step) / step;
                          domain(d);
                      }
  
                      return scale;
                  };
  
                  return scale;
              }
  
              function linear$2() {
                  var scale = continuous(identity$6, identity$6);
  
                  scale.copy = function () {
                      return copy(scale, linear$2());
                  };
  
                  initRange.apply(scale, arguments);
  
                  return linearish(scale);
              }
  
              function identity$7(domain) {
                  var unknown;
  
                  function scale(x) {
                      return isNaN(x = +x) ? unknown : x;
                  }
  
                  scale.invert = scale;
  
                  scale.domain = scale.range = function (_) {
                      return arguments.length ? (domain = map$3.call(_, number$2), scale) : domain.slice();
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  scale.copy = function () {
                      return identity$7(domain).unknown(unknown);
                  };
  
                  domain = arguments.length ? map$3.call(domain, number$2) : [0, 1];
  
                  return linearish(scale);
              }
  
              function nice(domain, interval) {
                  domain = domain.slice();
  
                  var i0 = 0,
                          i1 = domain.length - 1,
                          x0 = domain[i0],
                          x1 = domain[i1],
                          t;
  
                  if (x1 < x0) {
                      t = i0, i0 = i1, i1 = t;
                      t = x0, x0 = x1, x1 = t;
                  }
  
                  domain[i0] = interval.floor(x0);
                  domain[i1] = interval.ceil(x1);
                  return domain;
              }
  
              function transformLog(x) {
                  return Math.log(x);
              }
  
              function transformExp(x) {
                  return Math.exp(x);
              }
  
              function transformLogn(x) {
                  return -Math.log(-x);
              }
  
              function transformExpn(x) {
                  return -Math.exp(-x);
              }
  
              function pow10(x) {
                  return isFinite(x) ? +("1e" + x) : x < 0 ? 0 : x;
              }
  
              function powp(base) {
                  return base === 10 ? pow10
                          : base === Math.E ? Math.exp
                          : function (x) {
                              return Math.pow(base, x);
                          };
              }
  
              function logp(base) {
                  return base === Math.E ? Math.log
                          : base === 10 && Math.log10
                          || base === 2 && Math.log2
                          || (base = Math.log(base), function (x) {
                              return Math.log(x) / base;
                          });
              }
  
              function reflect(f) {
                  return function (x) {
                      return -f(-x);
                  };
              }
  
              function loggish(transform) {
                  var scale = transform(transformLog, transformExp),
                          domain = scale.domain,
                          base = 10,
                          logs,
                          pows;
  
                  function rescale() {
                      logs = logp(base), pows = powp(base);
                      if (domain()[0] < 0) {
                          logs = reflect(logs), pows = reflect(pows);
                          transform(transformLogn, transformExpn);
                      } else {
                          transform(transformLog, transformExp);
                      }
                      return scale;
                  }
  
                  scale.base = function (_) {
                      return arguments.length ? (base = +_, rescale()) : base;
                  };
  
                  scale.domain = function (_) {
                      return arguments.length ? (domain(_), rescale()) : domain();
                  };
  
                  scale.ticks = function (count) {
                      var d = domain(),
                              u = d[0],
                              v = d[d.length - 1],
                              r;
  
                      if (r = v < u)
                          i = u, u = v, v = i;
  
                      var i = logs(u),
                              j = logs(v),
                              p,
                              k,
                              t,
                              n = count == null ? 10 : +count,
                              z = [];
  
                      if (!(base % 1) && j - i < n) {
                          i = Math.round(i) - 1, j = Math.round(j) + 1;
                          if (u > 0)
                              for (; i < j; ++i) {
                                  for (k = 1, p = pows(i); k < base; ++k) {
                                      t = p * k;
                                      if (t < u)
                                          continue;
                                      if (t > v)
                                          break;
                                      z.push(t);
                                  }
                              }
                          else
                              for (; i < j; ++i) {
                                  for (k = base - 1, p = pows(i); k >= 1; --k) {
                                      t = p * k;
                                      if (t < u)
                                          continue;
                                      if (t > v)
                                          break;
                                      z.push(t);
                                  }
                              }
                      } else {
                          z = ticks(i, j, Math.min(j - i, n)).map(pows);
                      }
  
                      return r ? z.reverse() : z;
                  };
  
                  scale.tickFormat = function (count, specifier) {
                      if (specifier == null)
                          specifier = base === 10 ? ".0e" : ",";
                      if (typeof specifier !== "function")
                          specifier = exports.format(specifier);
                      if (count === Infinity)
                          return specifier;
                      if (count == null)
                          count = 10;
                      var k = Math.max(1, base * count / scale.ticks().length); // TODO fast estimate?
                      return function (d) {
                          var i = d / pows(Math.round(logs(d)));
                          if (i * base < base - 0.5)
                              i *= base;
                          return i <= k ? specifier(d) : "";
                      };
                  };
  
                  scale.nice = function () {
                      return domain(nice(domain(), {
                          floor: function (x) {
                              return pows(Math.floor(logs(x)));
                          },
                          ceil: function (x) {
                              return pows(Math.ceil(logs(x)));
                          }
                      }));
                  };
  
                  return scale;
              }
  
              function log$1() {
                  var scale = loggish(transformer$1()).domain([1, 10]);
  
                  scale.copy = function () {
                      return copy(scale, log$1()).base(scale.base());
                  };
  
                  initRange.apply(scale, arguments);
  
                  return scale;
              }
  
              function transformSymlog(c) {
                  return function (x) {
                      return Math.sign(x) * Math.log1p(Math.abs(x / c));
                  };
              }
  
              function transformSymexp(c) {
                  return function (x) {
                      return Math.sign(x) * Math.expm1(Math.abs(x)) * c;
                  };
              }
  
              function symlogish(transform) {
                  var c = 1, scale = transform(transformSymlog(c), transformSymexp(c));
  
                  scale.constant = function (_) {
                      return arguments.length ? transform(transformSymlog(c = +_), transformSymexp(c)) : c;
                  };
  
                  return linearish(scale);
              }
  
              function symlog() {
                  var scale = symlogish(transformer$1());
  
                  scale.copy = function () {
                      return copy(scale, symlog()).constant(scale.constant());
                  };
  
                  return initRange.apply(scale, arguments);
              }
  
              function transformPow(exponent) {
                  return function (x) {
                      return x < 0 ? -Math.pow(-x, exponent) : Math.pow(x, exponent);
                  };
              }
  
              function transformSqrt(x) {
                  return x < 0 ? -Math.sqrt(-x) : Math.sqrt(x);
              }
  
              function transformSquare(x) {
                  return x < 0 ? -x * x : x * x;
              }
  
              function powish(transform) {
                  var scale = transform(identity$6, identity$6),
                          exponent = 1;
  
                  function rescale() {
                      return exponent === 1 ? transform(identity$6, identity$6)
                              : exponent === 0.5 ? transform(transformSqrt, transformSquare)
                              : transform(transformPow(exponent), transformPow(1 / exponent));
                  }
  
                  scale.exponent = function (_) {
                      return arguments.length ? (exponent = +_, rescale()) : exponent;
                  };
  
                  return linearish(scale);
              }
  
              function pow$1() {
                  var scale = powish(transformer$1());
  
                  scale.copy = function () {
                      return copy(scale, pow$1()).exponent(scale.exponent());
                  };
  
                  initRange.apply(scale, arguments);
  
                  return scale;
              }
  
              function sqrt$1() {
                  return pow$1.apply(null, arguments).exponent(0.5);
              }
  
              function quantile() {
                  var domain = [],
                          range = [],
                          thresholds = [],
                          unknown;
  
                  function rescale() {
                      var i = 0, n = Math.max(1, range.length);
                      thresholds = new Array(n - 1);
                      while (++i < n)
                          thresholds[i - 1] = threshold(domain, i / n);
                      return scale;
                  }
  
                  function scale(x) {
                      return isNaN(x = +x) ? unknown : range[bisectRight(thresholds, x)];
                  }
  
                  scale.invertExtent = function (y) {
                      var i = range.indexOf(y);
                      return i < 0 ? [NaN, NaN] : [
                          i > 0 ? thresholds[i - 1] : domain[0],
                          i < thresholds.length ? thresholds[i] : domain[domain.length - 1]
                      ];
                  };
  
                  scale.domain = function (_) {
                      if (!arguments.length)
                          return domain.slice();
                      domain = [];
                      for (var i = 0, n = _.length, d; i < n; ++i)
                          if (d = _[i], d != null && !isNaN(d = +d))
                              domain.push(d);
                      domain.sort(ascending);
                      return rescale();
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (range = slice$5.call(_), rescale()) : range.slice();
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  scale.quantiles = function () {
                      return thresholds.slice();
                  };
  
                  scale.copy = function () {
                      return quantile()
                              .domain(domain)
                              .range(range)
                              .unknown(unknown);
                  };
  
                  return initRange.apply(scale, arguments);
              }
  
              function quantize$1() {
                  var x0 = 0,
                          x1 = 1,
                          n = 1,
                          domain = [0.5],
                          range = [0, 1],
                          unknown;
  
                  function scale(x) {
                      return x <= x ? range[bisectRight(domain, x, 0, n)] : unknown;
                  }
  
                  function rescale() {
                      var i = -1;
                      domain = new Array(n);
                      while (++i < n)
                          domain[i] = ((i + 1) * x1 - (i - n) * x0) / (n + 1);
                      return scale;
                  }
  
                  scale.domain = function (_) {
                      return arguments.length ? (x0 = +_[0], x1 = +_[1], rescale()) : [x0, x1];
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (n = (range = slice$5.call(_)).length - 1, rescale()) : range.slice();
                  };
  
                  scale.invertExtent = function (y) {
                      var i = range.indexOf(y);
                      return i < 0 ? [NaN, NaN]
                              : i < 1 ? [x0, domain[0]]
                              : i >= n ? [domain[n - 1], x1]
                              : [domain[i - 1], domain[i]];
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : scale;
                  };
  
                  scale.thresholds = function () {
                      return domain.slice();
                  };
  
                  scale.copy = function () {
                      return quantize$1()
                              .domain([x0, x1])
                              .range(range)
                              .unknown(unknown);
                  };
  
                  return initRange.apply(linearish(scale), arguments);
              }
  
              function threshold$1() {
                  var domain = [0.5],
                          range = [0, 1],
                          unknown,
                          n = 1;
  
                  function scale(x) {
                      return x <= x ? range[bisectRight(domain, x, 0, n)] : unknown;
                  }
  
                  scale.domain = function (_) {
                      return arguments.length ? (domain = slice$5.call(_), n = Math.min(domain.length, range.length - 1), scale) : domain.slice();
                  };
  
                  scale.range = function (_) {
                      return arguments.length ? (range = slice$5.call(_), n = Math.min(domain.length, range.length - 1), scale) : range.slice();
                  };
  
                  scale.invertExtent = function (y) {
                      var i = range.indexOf(y);
                      return [domain[i - 1], domain[i]];
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  scale.copy = function () {
                      return threshold$1()
                              .domain(domain)
                              .range(range)
                              .unknown(unknown);
                  };
  
                  return initRange.apply(scale, arguments);
              }
  
              var t0$1 = new Date,
                      t1$1 = new Date;
  
              function newInterval(floori, offseti, count, field) {
  
                  function interval(date) {
                      return floori(date = arguments.length === 0 ? new Date : new Date(+date)), date;
                  }
  
                  interval.floor = function (date) {
                      return floori(date = new Date(+date)), date;
                  };
  
                  interval.ceil = function (date) {
                      return floori(date = new Date(date - 1)), offseti(date, 1), floori(date), date;
                  };
  
                  interval.round = function (date) {
                      var d0 = interval(date),
                              d1 = interval.ceil(date);
                      return date - d0 < d1 - date ? d0 : d1;
                  };
  
                  interval.offset = function (date, step) {
                      return offseti(date = new Date(+date), step == null ? 1 : Math.floor(step)), date;
                  };
  
                  interval.range = function (start, stop, step) {
                      var range = [], previous;
                      start = interval.ceil(start);
                      step = step == null ? 1 : Math.floor(step);
                      if (!(start < stop) || !(step > 0))
                          return range; // also handles Invalid Date
                      do
                          range.push(previous = new Date(+start)), offseti(start, step), floori(start);
                      while (previous < start && start < stop);
                      return range;
                  };
  
                  interval.filter = function (test) {
                      return newInterval(function (date) {
                          if (date >= date)
                              while (floori(date), !test(date))
                                  date.setTime(date - 1);
                      }, function (date, step) {
                          if (date >= date) {
                              if (step < 0)
                                  while (++step <= 0) {
                                      while (offseti(date, -1), !test(date)) {
                                      } // eslint-disable-line no-empty
                                  }
                              else
                                  while (--step >= 0) {
                                      while (offseti(date, +1), !test(date)) {
                                      } // eslint-disable-line no-empty
                                  }
                          }
                      });
                  };
  
                  if (count) {
                      interval.count = function (start, end) {
                          t0$1.setTime(+start), t1$1.setTime(+end);
                          floori(t0$1), floori(t1$1);
                          return Math.floor(count(t0$1, t1$1));
                      };
  
                      interval.every = function (step) {
                          step = Math.floor(step);
                          return !isFinite(step) || !(step > 0) ? null
                                  : !(step > 1) ? interval
                                  : interval.filter(field
                                          ? function (d) {
                                              return field(d) % step === 0;
                                          }
                                  : function (d) {
                                      return interval.count(0, d) % step === 0;
                                  });
                      };
                  }
  
                  return interval;
              }
  
              var millisecond = newInterval(function () {
                  // noop
              }, function (date, step) {
                  date.setTime(+date + step);
              }, function (start, end) {
                  return end - start;
              });
  
  // An optimized implementation for this simple case.
              millisecond.every = function (k) {
                  k = Math.floor(k);
                  if (!isFinite(k) || !(k > 0))
                      return null;
                  if (!(k > 1))
                      return millisecond;
                  return newInterval(function (date) {
                      date.setTime(Math.floor(date / k) * k);
                  }, function (date, step) {
                      date.setTime(+date + step * k);
                  }, function (start, end) {
                      return (end - start) / k;
                  });
              };
              var milliseconds = millisecond.range;
  
              var durationSecond = 1e3;
              var durationMinute = 6e4;
              var durationHour = 36e5;
              var durationDay = 864e5;
              var durationWeek = 6048e5;
  
              var second = newInterval(function (date) {
                  date.setTime(date - date.getMilliseconds());
              }, function (date, step) {
                  date.setTime(+date + step * durationSecond);
              }, function (start, end) {
                  return (end - start) / durationSecond;
              }, function (date) {
                  return date.getUTCSeconds();
              });
              var seconds = second.range;
  
              var minute = newInterval(function (date) {
                  date.setTime(date - date.getMilliseconds() - date.getSeconds() * durationSecond);
              }, function (date, step) {
                  date.setTime(+date + step * durationMinute);
              }, function (start, end) {
                  return (end - start) / durationMinute;
              }, function (date) {
                  return date.getMinutes();
              });
              var minutes = minute.range;
  
              var hour = newInterval(function (date) {
                  date.setTime(date - date.getMilliseconds() - date.getSeconds() * durationSecond - date.getMinutes() * durationMinute);
              }, function (date, step) {
                  date.setTime(+date + step * durationHour);
              }, function (start, end) {
                  return (end - start) / durationHour;
              }, function (date) {
                  return date.getHours();
              });
              var hours = hour.range;
  
              var day = newInterval(function (date) {
                  date.setHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setDate(date.getDate() + step);
              }, function (start, end) {
                  return (end - start - (end.getTimezoneOffset() - start.getTimezoneOffset()) * durationMinute) / durationDay;
              }, function (date) {
                  return date.getDate() - 1;
              });
              var days = day.range;
  
              function weekday(i) {
                  return newInterval(function (date) {
                      date.setDate(date.getDate() - (date.getDay() + 7 - i) % 7);
                      date.setHours(0, 0, 0, 0);
                  }, function (date, step) {
                      date.setDate(date.getDate() + step * 7);
                  }, function (start, end) {
                      return (end - start - (end.getTimezoneOffset() - start.getTimezoneOffset()) * durationMinute) / durationWeek;
                  });
              }
  
              var sunday = weekday(0);
              var monday = weekday(1);
              var tuesday = weekday(2);
              var wednesday = weekday(3);
              var thursday = weekday(4);
              var friday = weekday(5);
              var saturday = weekday(6);
  
              var sundays = sunday.range;
              var mondays = monday.range;
              var tuesdays = tuesday.range;
              var wednesdays = wednesday.range;
              var thursdays = thursday.range;
              var fridays = friday.range;
              var saturdays = saturday.range;
  
              var month = newInterval(function (date) {
                  date.setDate(1);
                  date.setHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setMonth(date.getMonth() + step);
              }, function (start, end) {
                  return end.getMonth() - start.getMonth() + (end.getFullYear() - start.getFullYear()) * 12;
              }, function (date) {
                  return date.getMonth();
              });
              var months = month.range;
  
              var year = newInterval(function (date) {
                  date.setMonth(0, 1);
                  date.setHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setFullYear(date.getFullYear() + step);
              }, function (start, end) {
                  return end.getFullYear() - start.getFullYear();
              }, function (date) {
                  return date.getFullYear();
              });
  
  // An optimized implementation for this simple case.
              year.every = function (k) {
                  return !isFinite(k = Math.floor(k)) || !(k > 0) ? null : newInterval(function (date) {
                      date.setFullYear(Math.floor(date.getFullYear() / k) * k);
                      date.setMonth(0, 1);
                      date.setHours(0, 0, 0, 0);
                  }, function (date, step) {
                      date.setFullYear(date.getFullYear() + step * k);
                  });
              };
              var years = year.range;
  
              var utcMinute = newInterval(function (date) {
                  date.setUTCSeconds(0, 0);
              }, function (date, step) {
                  date.setTime(+date + step * durationMinute);
              }, function (start, end) {
                  return (end - start) / durationMinute;
              }, function (date) {
                  return date.getUTCMinutes();
              });
              var utcMinutes = utcMinute.range;
  
              var utcHour = newInterval(function (date) {
                  date.setUTCMinutes(0, 0, 0);
              }, function (date, step) {
                  date.setTime(+date + step * durationHour);
              }, function (start, end) {
                  return (end - start) / durationHour;
              }, function (date) {
                  return date.getUTCHours();
              });
              var utcHours = utcHour.range;
  
              var utcDay = newInterval(function (date) {
                  date.setUTCHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setUTCDate(date.getUTCDate() + step);
              }, function (start, end) {
                  return (end - start) / durationDay;
              }, function (date) {
                  return date.getUTCDate() - 1;
              });
              var utcDays = utcDay.range;
  
              function utcWeekday(i) {
                  return newInterval(function (date) {
                      date.setUTCDate(date.getUTCDate() - (date.getUTCDay() + 7 - i) % 7);
                      date.setUTCHours(0, 0, 0, 0);
                  }, function (date, step) {
                      date.setUTCDate(date.getUTCDate() + step * 7);
                  }, function (start, end) {
                      return (end - start) / durationWeek;
                  });
              }
  
              var utcSunday = utcWeekday(0);
              var utcMonday = utcWeekday(1);
              var utcTuesday = utcWeekday(2);
              var utcWednesday = utcWeekday(3);
              var utcThursday = utcWeekday(4);
              var utcFriday = utcWeekday(5);
              var utcSaturday = utcWeekday(6);
  
              var utcSundays = utcSunday.range;
              var utcMondays = utcMonday.range;
              var utcTuesdays = utcTuesday.range;
              var utcWednesdays = utcWednesday.range;
              var utcThursdays = utcThursday.range;
              var utcFridays = utcFriday.range;
              var utcSaturdays = utcSaturday.range;
  
              var utcMonth = newInterval(function (date) {
                  date.setUTCDate(1);
                  date.setUTCHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setUTCMonth(date.getUTCMonth() + step);
              }, function (start, end) {
                  return end.getUTCMonth() - start.getUTCMonth() + (end.getUTCFullYear() - start.getUTCFullYear()) * 12;
              }, function (date) {
                  return date.getUTCMonth();
              });
              var utcMonths = utcMonth.range;
  
              var utcYear = newInterval(function (date) {
                  date.setUTCMonth(0, 1);
                  date.setUTCHours(0, 0, 0, 0);
              }, function (date, step) {
                  date.setUTCFullYear(date.getUTCFullYear() + step);
              }, function (start, end) {
                  return end.getUTCFullYear() - start.getUTCFullYear();
              }, function (date) {
                  return date.getUTCFullYear();
              });
  
  // An optimized implementation for this simple case.
              utcYear.every = function (k) {
                  return !isFinite(k = Math.floor(k)) || !(k > 0) ? null : newInterval(function (date) {
                      date.setUTCFullYear(Math.floor(date.getUTCFullYear() / k) * k);
                      date.setUTCMonth(0, 1);
                      date.setUTCHours(0, 0, 0, 0);
                  }, function (date, step) {
                      date.setUTCFullYear(date.getUTCFullYear() + step * k);
                  });
              };
              var utcYears = utcYear.range;
  
              function localDate(d) {
                  if (0 <= d.y && d.y < 100) {
                      var date = new Date(-1, d.m, d.d, d.H, d.M, d.S, d.L);
                      date.setFullYear(d.y);
                      return date;
                  }
                  return new Date(d.y, d.m, d.d, d.H, d.M, d.S, d.L);
              }
  
              function utcDate(d) {
                  if (0 <= d.y && d.y < 100) {
                      var date = new Date(Date.UTC(-1, d.m, d.d, d.H, d.M, d.S, d.L));
                      date.setUTCFullYear(d.y);
                      return date;
                  }
                  return new Date(Date.UTC(d.y, d.m, d.d, d.H, d.M, d.S, d.L));
              }
  
              function newDate(y, m, d) {
                  return {y: y, m: m, d: d, H: 0, M: 0, S: 0, L: 0};
              }
  
              function formatLocale$1(locale) {
                  var locale_dateTime = locale.dateTime,
                          locale_date = locale.date,
                          locale_time = locale.time,
                          locale_periods = locale.periods,
                          locale_weekdays = locale.days,
                          locale_shortWeekdays = locale.shortDays,
                          locale_months = locale.months,
                          locale_shortMonths = locale.shortMonths;
  
                  var periodRe = formatRe(locale_periods),
                          periodLookup = formatLookup(locale_periods),
                          weekdayRe = formatRe(locale_weekdays),
                          weekdayLookup = formatLookup(locale_weekdays),
                          shortWeekdayRe = formatRe(locale_shortWeekdays),
                          shortWeekdayLookup = formatLookup(locale_shortWeekdays),
                          monthRe = formatRe(locale_months),
                          monthLookup = formatLookup(locale_months),
                          shortMonthRe = formatRe(locale_shortMonths),
                          shortMonthLookup = formatLookup(locale_shortMonths);
  
                  var formats = {
                      "a": formatShortWeekday,
                      "A": formatWeekday,
                      "b": formatShortMonth,
                      "B": formatMonth,
                      "c": null,
                      "d": formatDayOfMonth,
                      "e": formatDayOfMonth,
                      "f": formatMicroseconds,
                      "H": formatHour24,
                      "I": formatHour12,
                      "j": formatDayOfYear,
                      "L": formatMilliseconds,
                      "m": formatMonthNumber,
                      "M": formatMinutes,
                      "p": formatPeriod,
                      "q": formatQuarter,
                      "Q": formatUnixTimestamp,
                      "s": formatUnixTimestampSeconds,
                      "S": formatSeconds,
                      "u": formatWeekdayNumberMonday,
                      "U": formatWeekNumberSunday,
                      "V": formatWeekNumberISO,
                      "w": formatWeekdayNumberSunday,
                      "W": formatWeekNumberMonday,
                      "x": null,
                      "X": null,
                      "y": formatYear$1,
                      "Y": formatFullYear,
                      "Z": formatZone,
                      "%": formatLiteralPercent
                  };
  
                  var utcFormats = {
                      "a": formatUTCShortWeekday,
                      "A": formatUTCWeekday,
                      "b": formatUTCShortMonth,
                      "B": formatUTCMonth,
                      "c": null,
                      "d": formatUTCDayOfMonth,
                      "e": formatUTCDayOfMonth,
                      "f": formatUTCMicroseconds,
                      "H": formatUTCHour24,
                      "I": formatUTCHour12,
                      "j": formatUTCDayOfYear,
                      "L": formatUTCMilliseconds,
                      "m": formatUTCMonthNumber,
                      "M": formatUTCMinutes,
                      "p": formatUTCPeriod,
                      "q": formatUTCQuarter,
                      "Q": formatUnixTimestamp,
                      "s": formatUnixTimestampSeconds,
                      "S": formatUTCSeconds,
                      "u": formatUTCWeekdayNumberMonday,
                      "U": formatUTCWeekNumberSunday,
                      "V": formatUTCWeekNumberISO,
                      "w": formatUTCWeekdayNumberSunday,
                      "W": formatUTCWeekNumberMonday,
                      "x": null,
                      "X": null,
                      "y": formatUTCYear,
                      "Y": formatUTCFullYear,
                      "Z": formatUTCZone,
                      "%": formatLiteralPercent
                  };
  
                  var parses = {
                      "a": parseShortWeekday,
                      "A": parseWeekday,
                      "b": parseShortMonth,
                      "B": parseMonth,
                      "c": parseLocaleDateTime,
                      "d": parseDayOfMonth,
                      "e": parseDayOfMonth,
                      "f": parseMicroseconds,
                      "H": parseHour24,
                      "I": parseHour24,
                      "j": parseDayOfYear,
                      "L": parseMilliseconds,
                      "m": parseMonthNumber,
                      "M": parseMinutes,
                      "p": parsePeriod,
                      "q": parseQuarter,
                      "Q": parseUnixTimestamp,
                      "s": parseUnixTimestampSeconds,
                      "S": parseSeconds,
                      "u": parseWeekdayNumberMonday,
                      "U": parseWeekNumberSunday,
                      "V": parseWeekNumberISO,
                      "w": parseWeekdayNumberSunday,
                      "W": parseWeekNumberMonday,
                      "x": parseLocaleDate,
                      "X": parseLocaleTime,
                      "y": parseYear,
                      "Y": parseFullYear,
                      "Z": parseZone,
                      "%": parseLiteralPercent
                  };
  
                  // These recursive directive definitions must be deferred.
                  formats.x = newFormat(locale_date, formats);
                  formats.X = newFormat(locale_time, formats);
                  formats.c = newFormat(locale_dateTime, formats);
                  utcFormats.x = newFormat(locale_date, utcFormats);
                  utcFormats.X = newFormat(locale_time, utcFormats);
                  utcFormats.c = newFormat(locale_dateTime, utcFormats);
  
                  function newFormat(specifier, formats) {
                      return function (date) {
                          var string = [],
                                  i = -1,
                                  j = 0,
                                  n = specifier.length,
                                  c,
                                  pad,
                                  format;
  
                          if (!(date instanceof Date))
                              date = new Date(+date);
  
                          while (++i < n) {
                              if (specifier.charCodeAt(i) === 37) {
                                  string.push(specifier.slice(j, i));
                                  if ((pad = pads[c = specifier.charAt(++i)]) != null)
                                      c = specifier.charAt(++i);
                                  else
                                      pad = c === "e" ? " " : "0";
                                  if (format = formats[c])
                                      c = format(date, pad);
                                  string.push(c);
                                  j = i + 1;
                              }
                          }
  
                          string.push(specifier.slice(j, i));
                          return string.join("");
                      };
                  }
  
                  function newParse(specifier, Z) {
                      return function (string) {
                          var d = newDate(1900, undefined, 1),
                                  i = parseSpecifier(d, specifier, string += "", 0),
                                  week, day$1;
                          if (i != string.length)
                              return null;
  
                          // If a UNIX timestamp is specified, return it.
                          if ("Q" in d)
                              return new Date(d.Q);
                          if ("s" in d)
                              return new Date(d.s * 1000 + ("L" in d ? d.L : 0));
  
                          // If this is utcParse, never use the local timezone.
                          if (Z && !("Z" in d))
                              d.Z = 0;
  
                          // The am-pm flag is 0 for AM, and 1 for PM.
                          if ("p" in d)
                              d.H = d.H % 12 + d.p * 12;
  
                          // If the month was not specified, inherit from the quarter.
                          if (d.m === undefined)
                              d.m = "q" in d ? d.q : 0;
  
                          // Convert day-of-week and week-of-year to day-of-year.
                          if ("V" in d) {
                              if (d.V < 1 || d.V > 53)
                                  return null;
                              if (!("w" in d))
                                  d.w = 1;
                              if ("Z" in d) {
                                  week = utcDate(newDate(d.y, 0, 1)), day$1 = week.getUTCDay();
                                  week = day$1 > 4 || day$1 === 0 ? utcMonday.ceil(week) : utcMonday(week);
                                  week = utcDay.offset(week, (d.V - 1) * 7);
                                  d.y = week.getUTCFullYear();
                                  d.m = week.getUTCMonth();
                                  d.d = week.getUTCDate() + (d.w + 6) % 7;
                              } else {
                                  week = localDate(newDate(d.y, 0, 1)), day$1 = week.getDay();
                                  week = day$1 > 4 || day$1 === 0 ? monday.ceil(week) : monday(week);
                                  week = day.offset(week, (d.V - 1) * 7);
                                  d.y = week.getFullYear();
                                  d.m = week.getMonth();
                                  d.d = week.getDate() + (d.w + 6) % 7;
                              }
                          } else if ("W" in d || "U" in d) {
                              if (!("w" in d))
                                  d.w = "u" in d ? d.u % 7 : "W" in d ? 1 : 0;
                              day$1 = "Z" in d ? utcDate(newDate(d.y, 0, 1)).getUTCDay() : localDate(newDate(d.y, 0, 1)).getDay();
                              d.m = 0;
                              d.d = "W" in d ? (d.w + 6) % 7 + d.W * 7 - (day$1 + 5) % 7 : d.w + d.U * 7 - (day$1 + 6) % 7;
                          }
  
                          // If a time zone is specified, all fields are interpreted as UTC and then
                          // offset according to the specified time zone.
                          if ("Z" in d) {
                              d.H += d.Z / 100 | 0;
                              d.M += d.Z % 100;
                              return utcDate(d);
                          }
  
                          // Otherwise, all fields are in local time.
                          return localDate(d);
                      };
                  }
  
                  function parseSpecifier(d, specifier, string, j) {
                      var i = 0,
                              n = specifier.length,
                              m = string.length,
                              c,
                              parse;
  
                      while (i < n) {
                          if (j >= m)
                              return -1;
                          c = specifier.charCodeAt(i++);
                          if (c === 37) {
                              c = specifier.charAt(i++);
                              parse = parses[c in pads ? specifier.charAt(i++) : c];
                              if (!parse || ((j = parse(d, string, j)) < 0))
                                  return -1;
                          } else if (c != string.charCodeAt(j++)) {
                              return -1;
                          }
                      }
  
                      return j;
                  }
  
                  function parsePeriod(d, string, i) {
                      var n = periodRe.exec(string.slice(i));
                      return n ? (d.p = periodLookup[n[0].toLowerCase()], i + n[0].length) : -1;
                  }
  
                  function parseShortWeekday(d, string, i) {
                      var n = shortWeekdayRe.exec(string.slice(i));
                      return n ? (d.w = shortWeekdayLookup[n[0].toLowerCase()], i + n[0].length) : -1;
                  }
  
                  function parseWeekday(d, string, i) {
                      var n = weekdayRe.exec(string.slice(i));
                      return n ? (d.w = weekdayLookup[n[0].toLowerCase()], i + n[0].length) : -1;
                  }
  
                  function parseShortMonth(d, string, i) {
                      var n = shortMonthRe.exec(string.slice(i));
                      return n ? (d.m = shortMonthLookup[n[0].toLowerCase()], i + n[0].length) : -1;
                  }
  
                  function parseMonth(d, string, i) {
                      var n = monthRe.exec(string.slice(i));
                      return n ? (d.m = monthLookup[n[0].toLowerCase()], i + n[0].length) : -1;
                  }
  
                  function parseLocaleDateTime(d, string, i) {
                      return parseSpecifier(d, locale_dateTime, string, i);
                  }
  
                  function parseLocaleDate(d, string, i) {
                      return parseSpecifier(d, locale_date, string, i);
                  }
  
                  function parseLocaleTime(d, string, i) {
                      return parseSpecifier(d, locale_time, string, i);
                  }
  
                  function formatShortWeekday(d) {
                      return locale_shortWeekdays[d.getDay()];
                  }
  
                  function formatWeekday(d) {
                      return locale_weekdays[d.getDay()];
                  }
  
                  function formatShortMonth(d) {
                      return locale_shortMonths[d.getMonth()];
                  }
  
                  function formatMonth(d) {
                      return locale_months[d.getMonth()];
                  }
  
                  function formatPeriod(d) {
                      return locale_periods[+(d.getHours() >= 12)];
                  }
  
                  function formatQuarter(d) {
                      return 1 + ~~(d.getMonth() / 3);
                  }
  
                  function formatUTCShortWeekday(d) {
                      return locale_shortWeekdays[d.getUTCDay()];
                  }
  
                  function formatUTCWeekday(d) {
                      return locale_weekdays[d.getUTCDay()];
                  }
  
                  function formatUTCShortMonth(d) {
                      return locale_shortMonths[d.getUTCMonth()];
                  }
  
                  function formatUTCMonth(d) {
                      return locale_months[d.getUTCMonth()];
                  }
  
                  function formatUTCPeriod(d) {
                      return locale_periods[+(d.getUTCHours() >= 12)];
                  }
  
                  function formatUTCQuarter(d) {
                      return 1 + ~~(d.getUTCMonth() / 3);
                  }
  
                  return {
                      format: function (specifier) {
                          var f = newFormat(specifier += "", formats);
                          f.toString = function () {
                              return specifier;
                          };
                          return f;
                      },
                      parse: function (specifier) {
                          var p = newParse(specifier += "", false);
                          p.toString = function () {
                              return specifier;
                          };
                          return p;
                      },
                      utcFormat: function (specifier) {
                          var f = newFormat(specifier += "", utcFormats);
                          f.toString = function () {
                              return specifier;
                          };
                          return f;
                      },
                      utcParse: function (specifier) {
                          var p = newParse(specifier += "", true);
                          p.toString = function () {
                              return specifier;
                          };
                          return p;
                      }
                  };
              }
  
              var pads = {"-": "", "_": " ", "0": "0"},
                      numberRe = /^\s*\d+/, // note: ignores next directive
                      percentRe = /^%/,
                      requoteRe = /[\\^$*+?|[\]().{}]/g;
  
              function pad$1(value, fill, width) {
                  var sign = value < 0 ? "-" : "",
                          string = (sign ? -value : value) + "",
                          length = string.length;
                  return sign + (length < width ? new Array(width - length + 1).join(fill) + string : string);
              }
  
              function requote(s) {
                  return s.replace(requoteRe, "\\$&");
              }
  
              function formatRe(names) {
                  return new RegExp("^(?:" + names.map(requote).join("|") + ")", "i");
              }
  
              function formatLookup(names) {
                  var map = {}, i = -1, n = names.length;
                  while (++i < n)
                      map[names[i].toLowerCase()] = i;
                  return map;
              }
  
              function parseWeekdayNumberSunday(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 1));
                  return n ? (d.w = +n[0], i + n[0].length) : -1;
              }
  
              function parseWeekdayNumberMonday(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 1));
                  return n ? (d.u = +n[0], i + n[0].length) : -1;
              }
  
              function parseWeekNumberSunday(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.U = +n[0], i + n[0].length) : -1;
              }
  
              function parseWeekNumberISO(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.V = +n[0], i + n[0].length) : -1;
              }
  
              function parseWeekNumberMonday(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.W = +n[0], i + n[0].length) : -1;
              }
  
              function parseFullYear(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 4));
                  return n ? (d.y = +n[0], i + n[0].length) : -1;
              }
  
              function parseYear(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.y = +n[0] + (+n[0] > 68 ? 1900 : 2000), i + n[0].length) : -1;
              }
  
              function parseZone(d, string, i) {
                  var n = /^(Z)|([+-]\d\d)(?::?(\d\d))?/.exec(string.slice(i, i + 6));
                  return n ? (d.Z = n[1] ? 0 : -(n[2] + (n[3] || "00")), i + n[0].length) : -1;
              }
  
              function parseQuarter(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 1));
                  return n ? (d.q = n[0] * 3 - 3, i + n[0].length) : -1;
              }
  
              function parseMonthNumber(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.m = n[0] - 1, i + n[0].length) : -1;
              }
  
              function parseDayOfMonth(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.d = +n[0], i + n[0].length) : -1;
              }
  
              function parseDayOfYear(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 3));
                  return n ? (d.m = 0, d.d = +n[0], i + n[0].length) : -1;
              }
  
              function parseHour24(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.H = +n[0], i + n[0].length) : -1;
              }
  
              function parseMinutes(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.M = +n[0], i + n[0].length) : -1;
              }
  
              function parseSeconds(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 2));
                  return n ? (d.S = +n[0], i + n[0].length) : -1;
              }
  
              function parseMilliseconds(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 3));
                  return n ? (d.L = +n[0], i + n[0].length) : -1;
              }
  
              function parseMicroseconds(d, string, i) {
                  var n = numberRe.exec(string.slice(i, i + 6));
                  return n ? (d.L = Math.floor(n[0] / 1000), i + n[0].length) : -1;
              }
  
              function parseLiteralPercent(d, string, i) {
                  var n = percentRe.exec(string.slice(i, i + 1));
                  return n ? i + n[0].length : -1;
              }
  
              function parseUnixTimestamp(d, string, i) {
                  var n = numberRe.exec(string.slice(i));
                  return n ? (d.Q = +n[0], i + n[0].length) : -1;
              }
  
              function parseUnixTimestampSeconds(d, string, i) {
                  var n = numberRe.exec(string.slice(i));
                  return n ? (d.s = +n[0], i + n[0].length) : -1;
              }
  
              function formatDayOfMonth(d, p) {
                  return pad$1(d.getDate(), p, 2);
              }
  
              function formatHour24(d, p) {
                  return pad$1(d.getHours(), p, 2);
              }
  
              function formatHour12(d, p) {
                  return pad$1(d.getHours() % 12 || 12, p, 2);
              }
  
              function formatDayOfYear(d, p) {
                  return pad$1(1 + day.count(year(d), d), p, 3);
              }
  
              function formatMilliseconds(d, p) {
                  return pad$1(d.getMilliseconds(), p, 3);
              }
  
              function formatMicroseconds(d, p) {
                  return formatMilliseconds(d, p) + "000";
              }
  
              function formatMonthNumber(d, p) {
                  return pad$1(d.getMonth() + 1, p, 2);
              }
  
              function formatMinutes(d, p) {
                  return pad$1(d.getMinutes(), p, 2);
              }
  
              function formatSeconds(d, p) {
                  return pad$1(d.getSeconds(), p, 2);
              }
  
              function formatWeekdayNumberMonday(d) {
                  var day = d.getDay();
                  return day === 0 ? 7 : day;
              }
  
              function formatWeekNumberSunday(d, p) {
                  return pad$1(sunday.count(year(d) - 1, d), p, 2);
              }
  
              function formatWeekNumberISO(d, p) {
                  var day = d.getDay();
                  d = (day >= 4 || day === 0) ? thursday(d) : thursday.ceil(d);
                  return pad$1(thursday.count(year(d), d) + (year(d).getDay() === 4), p, 2);
              }
  
              function formatWeekdayNumberSunday(d) {
                  return d.getDay();
              }
  
              function formatWeekNumberMonday(d, p) {
                  return pad$1(monday.count(year(d) - 1, d), p, 2);
              }
  
              function formatYear$1(d, p) {
                  return pad$1(d.getFullYear() % 100, p, 2);
              }
  
              function formatFullYear(d, p) {
                  return pad$1(d.getFullYear() % 10000, p, 4);
              }
  
              function formatZone(d) {
                  var z = d.getTimezoneOffset();
                  return (z > 0 ? "-" : (z *= -1, "+"))
                          + pad$1(z / 60 | 0, "0", 2)
                          + pad$1(z % 60, "0", 2);
              }
  
              function formatUTCDayOfMonth(d, p) {
                  return pad$1(d.getUTCDate(), p, 2);
              }
  
              function formatUTCHour24(d, p) {
                  return pad$1(d.getUTCHours(), p, 2);
              }
  
              function formatUTCHour12(d, p) {
                  return pad$1(d.getUTCHours() % 12 || 12, p, 2);
              }
  
              function formatUTCDayOfYear(d, p) {
                  return pad$1(1 + utcDay.count(utcYear(d), d), p, 3);
              }
  
              function formatUTCMilliseconds(d, p) {
                  return pad$1(d.getUTCMilliseconds(), p, 3);
              }
  
              function formatUTCMicroseconds(d, p) {
                  return formatUTCMilliseconds(d, p) + "000";
              }
  
              function formatUTCMonthNumber(d, p) {
                  return pad$1(d.getUTCMonth() + 1, p, 2);
              }
  
              function formatUTCMinutes(d, p) {
                  return pad$1(d.getUTCMinutes(), p, 2);
              }
  
              function formatUTCSeconds(d, p) {
                  return pad$1(d.getUTCSeconds(), p, 2);
              }
  
              function formatUTCWeekdayNumberMonday(d) {
                  var dow = d.getUTCDay();
                  return dow === 0 ? 7 : dow;
              }
  
              function formatUTCWeekNumberSunday(d, p) {
                  return pad$1(utcSunday.count(utcYear(d) - 1, d), p, 2);
              }
  
              function formatUTCWeekNumberISO(d, p) {
                  var day = d.getUTCDay();
                  d = (day >= 4 || day === 0) ? utcThursday(d) : utcThursday.ceil(d);
                  return pad$1(utcThursday.count(utcYear(d), d) + (utcYear(d).getUTCDay() === 4), p, 2);
              }
  
              function formatUTCWeekdayNumberSunday(d) {
                  return d.getUTCDay();
              }
  
              function formatUTCWeekNumberMonday(d, p) {
                  return pad$1(utcMonday.count(utcYear(d) - 1, d), p, 2);
              }
  
              function formatUTCYear(d, p) {
                  return pad$1(d.getUTCFullYear() % 100, p, 2);
              }
  
              function formatUTCFullYear(d, p) {
                  return pad$1(d.getUTCFullYear() % 10000, p, 4);
              }
  
              function formatUTCZone() {
                  return "+0000";
              }
  
              function formatLiteralPercent() {
                  return "%";
              }
  
              function formatUnixTimestamp(d) {
                  return +d;
              }
  
              function formatUnixTimestampSeconds(d) {
                  return Math.floor(+d / 1000);
              }
  
              var locale$1;
  
              defaultLocale$1({
                  dateTime: "%x, %X",
                  date: "%-m/%-d/%Y",
                  time: "%-I:%M:%S %p",
                  periods: ["AM", "PM"],
                  days: ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"],
                  shortDays: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
                  months: ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"],
                  shortMonths: ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
              });
  
              function defaultLocale$1(definition) {
                  locale$1 = formatLocale$1(definition);
                  exports.timeFormat = locale$1.format;
                  exports.timeParse = locale$1.parse;
                  exports.utcFormat = locale$1.utcFormat;
                  exports.utcParse = locale$1.utcParse;
                  return locale$1;
              }
  
              var isoSpecifier = "%Y-%m-%dT%H:%M:%S.%LZ";
  
              function formatIsoNative(date) {
                  return date.toISOString();
              }
  
              var formatIso = Date.prototype.toISOString
                      ? formatIsoNative
                      : exports.utcFormat(isoSpecifier);
  
              function parseIsoNative(string) {
                  var date = new Date(string);
                  return isNaN(date) ? null : date;
              }
  
              var parseIso = +new Date("2000-01-01T00:00:00.000Z")
                      ? parseIsoNative
                      : exports.utcParse(isoSpecifier);
  
              var durationSecond$1 = 1000,
                      durationMinute$1 = durationSecond$1 * 60,
                      durationHour$1 = durationMinute$1 * 60,
                      durationDay$1 = durationHour$1 * 24,
                      durationWeek$1 = durationDay$1 * 7,
                      durationMonth = durationDay$1 * 30,
                      durationYear = durationDay$1 * 365;
  
              function date$1(t) {
                  return new Date(t);
              }
  
              function number$3(t) {
                  return t instanceof Date ? +t : +new Date(+t);
              }
  
              function calendar(year, month, week, day, hour, minute, second, millisecond, format) {
                  var scale = continuous(identity$6, identity$6),
                          invert = scale.invert,
                          domain = scale.domain;
  
                  var formatMillisecond = format(".%L"),
                          formatSecond = format(":%S"),
                          formatMinute = format("%I:%M"),
                          formatHour = format("%I %p"),
                          formatDay = format("%a %d"),
                          formatWeek = format("%b %d"),
                          formatMonth = format("%B"),
                          formatYear = format("%Y");
  
                  var tickIntervals = [
                      [second, 1, durationSecond$1],
                      [second, 5, 5 * durationSecond$1],
                      [second, 15, 15 * durationSecond$1],
                      [second, 30, 30 * durationSecond$1],
                      [minute, 1, durationMinute$1],
                      [minute, 5, 5 * durationMinute$1],
                      [minute, 15, 15 * durationMinute$1],
                      [minute, 30, 30 * durationMinute$1],
                      [hour, 1, durationHour$1],
                      [hour, 3, 3 * durationHour$1],
                      [hour, 6, 6 * durationHour$1],
                      [hour, 12, 12 * durationHour$1],
                      [day, 1, durationDay$1],
                      [day, 2, 2 * durationDay$1],
                      [week, 1, durationWeek$1],
                      [month, 1, durationMonth],
                      [month, 3, 3 * durationMonth],
                      [year, 1, durationYear]
                  ];
  
                  function tickFormat(date) {
                      return (second(date) < date ? formatMillisecond
                              : minute(date) < date ? formatSecond
                              : hour(date) < date ? formatMinute
                              : day(date) < date ? formatHour
                              : month(date) < date ? (week(date) < date ? formatDay : formatWeek)
                              : year(date) < date ? formatMonth
                              : formatYear)(date);
                  }
  
                  function tickInterval(interval, start, stop, step) {
                      if (interval == null)
                          interval = 10;
  
                      // If a desired tick count is specified, pick a reasonable tick interval
                      // based on the extent of the domain and a rough estimate of tick size.
                      // Otherwise, assume interval is already a time interval and use it.
                      if (typeof interval === "number") {
                          var target = Math.abs(stop - start) / interval,
                                  i = bisector(function (i) {
                                      return i[2];
                                  }).right(tickIntervals, target);
                          if (i === tickIntervals.length) {
                              step = tickStep(start / durationYear, stop / durationYear, interval);
                              interval = year;
                          } else if (i) {
                              i = tickIntervals[target / tickIntervals[i - 1][2] < tickIntervals[i][2] / target ? i - 1 : i];
                              step = i[1];
                              interval = i[0];
                          } else {
                              step = Math.max(tickStep(start, stop, interval), 1);
                              interval = millisecond;
                          }
                      }
  
                      return step == null ? interval : interval.every(step);
                  }
  
                  scale.invert = function (y) {
                      return new Date(invert(y));
                  };
  
                  scale.domain = function (_) {
                      return arguments.length ? domain(map$3.call(_, number$3)) : domain().map(date$1);
                  };
  
                  scale.ticks = function (interval, step) {
                      var d = domain(),
                              t0 = d[0],
                              t1 = d[d.length - 1],
                              r = t1 < t0,
                              t;
                      if (r)
                          t = t0, t0 = t1, t1 = t;
                      t = tickInterval(interval, t0, t1, step);
                      t = t ? t.range(t0, t1 + 1) : []; // inclusive stop
                      return r ? t.reverse() : t;
                  };
  
                  scale.tickFormat = function (count, specifier) {
                      return specifier == null ? tickFormat : format(specifier);
                  };
  
                  scale.nice = function (interval, step) {
                      var d = domain();
                      return (interval = tickInterval(interval, d[0], d[d.length - 1], step))
                              ? domain(nice(d, interval))
                              : scale;
                  };
  
                  scale.copy = function () {
                      return copy(scale, calendar(year, month, week, day, hour, minute, second, millisecond, format));
                  };
  
                  return scale;
              }
  
              function time() {
                  return initRange.apply(calendar(year, month, sunday, day, hour, minute, second, millisecond, exports.timeFormat).domain([new Date(2000, 0, 1), new Date(2000, 0, 2)]), arguments);
              }
  
              function utcTime() {
                  return initRange.apply(calendar(utcYear, utcMonth, utcSunday, utcDay, utcHour, utcMinute, second, millisecond, exports.utcFormat).domain([Date.UTC(2000, 0, 1), Date.UTC(2000, 0, 2)]), arguments);
              }
  
              function transformer$2() {
                  var x0 = 0,
                          x1 = 1,
                          t0,
                          t1,
                          k10,
                          transform,
                          interpolator = identity$6,
                          clamp = false,
                          unknown;
  
                  function scale(x) {
                      return isNaN(x = +x) ? unknown : interpolator(k10 === 0 ? 0.5 : (x = (transform(x) - t0) * k10, clamp ? Math.max(0, Math.min(1, x)) : x));
                  }
  
                  scale.domain = function (_) {
                      return arguments.length ? (t0 = transform(x0 = +_[0]), t1 = transform(x1 = +_[1]), k10 = t0 === t1 ? 0 : 1 / (t1 - t0), scale) : [x0, x1];
                  };
  
                  scale.clamp = function (_) {
                      return arguments.length ? (clamp = !!_, scale) : clamp;
                  };
  
                  scale.interpolator = function (_) {
                      return arguments.length ? (interpolator = _, scale) : interpolator;
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  return function (t) {
                      transform = t, t0 = t(x0), t1 = t(x1), k10 = t0 === t1 ? 0 : 1 / (t1 - t0);
                      return scale;
                  };
              }
  
              function copy$1(source, target) {
                  return target
                          .domain(source.domain())
                          .interpolator(source.interpolator())
                          .clamp(source.clamp())
                          .unknown(source.unknown());
              }
  
              function sequential() {
                  var scale = linearish(transformer$2()(identity$6));
  
                  scale.copy = function () {
                      return copy$1(scale, sequential());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function sequentialLog() {
                  var scale = loggish(transformer$2()).domain([1, 10]);
  
                  scale.copy = function () {
                      return copy$1(scale, sequentialLog()).base(scale.base());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function sequentialSymlog() {
                  var scale = symlogish(transformer$2());
  
                  scale.copy = function () {
                      return copy$1(scale, sequentialSymlog()).constant(scale.constant());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function sequentialPow() {
                  var scale = powish(transformer$2());
  
                  scale.copy = function () {
                      return copy$1(scale, sequentialPow()).exponent(scale.exponent());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function sequentialSqrt() {
                  return sequentialPow.apply(null, arguments).exponent(0.5);
              }
  
              function sequentialQuantile() {
                  var domain = [],
                          interpolator = identity$6;
  
                  function scale(x) {
                      if (!isNaN(x = +x))
                          return interpolator((bisectRight(domain, x) - 1) / (domain.length - 1));
                  }
  
                  scale.domain = function (_) {
                      if (!arguments.length)
                          return domain.slice();
                      domain = [];
                      for (var i = 0, n = _.length, d; i < n; ++i)
                          if (d = _[i], d != null && !isNaN(d = +d))
                              domain.push(d);
                      domain.sort(ascending);
                      return scale;
                  };
  
                  scale.interpolator = function (_) {
                      return arguments.length ? (interpolator = _, scale) : interpolator;
                  };
  
                  scale.copy = function () {
                      return sequentialQuantile(interpolator).domain(domain);
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function transformer$3() {
                  var x0 = 0,
                          x1 = 0.5,
                          x2 = 1,
                          t0,
                          t1,
                          t2,
                          k10,
                          k21,
                          interpolator = identity$6,
                          transform,
                          clamp = false,
                          unknown;
  
                  function scale(x) {
                      return isNaN(x = +x) ? unknown : (x = 0.5 + ((x = +transform(x)) - t1) * (x < t1 ? k10 : k21), interpolator(clamp ? Math.max(0, Math.min(1, x)) : x));
                  }
  
                  scale.domain = function (_) {
                      return arguments.length ? (t0 = transform(x0 = +_[0]), t1 = transform(x1 = +_[1]), t2 = transform(x2 = +_[2]), k10 = t0 === t1 ? 0 : 0.5 / (t1 - t0), k21 = t1 === t2 ? 0 : 0.5 / (t2 - t1), scale) : [x0, x1, x2];
                  };
  
                  scale.clamp = function (_) {
                      return arguments.length ? (clamp = !!_, scale) : clamp;
                  };
  
                  scale.interpolator = function (_) {
                      return arguments.length ? (interpolator = _, scale) : interpolator;
                  };
  
                  scale.unknown = function (_) {
                      return arguments.length ? (unknown = _, scale) : unknown;
                  };
  
                  return function (t) {
                      transform = t, t0 = t(x0), t1 = t(x1), t2 = t(x2), k10 = t0 === t1 ? 0 : 0.5 / (t1 - t0), k21 = t1 === t2 ? 0 : 0.5 / (t2 - t1);
                      return scale;
                  };
              }
  
              function diverging() {
                  var scale = linearish(transformer$3()(identity$6));
  
                  scale.copy = function () {
                      return copy$1(scale, diverging());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function divergingLog() {
                  var scale = loggish(transformer$3()).domain([0.1, 1, 10]);
  
                  scale.copy = function () {
                      return copy$1(scale, divergingLog()).base(scale.base());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function divergingSymlog() {
                  var scale = symlogish(transformer$3());
  
                  scale.copy = function () {
                      return copy$1(scale, divergingSymlog()).constant(scale.constant());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function divergingPow() {
                  var scale = powish(transformer$3());
  
                  scale.copy = function () {
                      return copy$1(scale, divergingPow()).exponent(scale.exponent());
                  };
  
                  return initInterpolator.apply(scale, arguments);
              }
  
              function divergingSqrt() {
                  return divergingPow.apply(null, arguments).exponent(0.5);
              }
  
              function colors(specifier) {
                  var n = specifier.length / 6 | 0, colors = new Array(n), i = 0;
                  while (i < n)
                      colors[i] = "#" + specifier.slice(i * 6, ++i * 6);
                  return colors;
              }
  
              var category10 = colors("1f77b4ff7f0e2ca02cd627289467bd8c564be377c27f7f7fbcbd2217becf");
  
              var Accent = colors("7fc97fbeaed4fdc086ffff99386cb0f0027fbf5b17666666");
  
              var Dark2 = colors("1b9e77d95f027570b3e7298a66a61ee6ab02a6761d666666");
  
              var Paired = colors("a6cee31f78b4b2df8a33a02cfb9a99e31a1cfdbf6fff7f00cab2d66a3d9affff99b15928");
  
              var Pastel1 = colors("fbb4aeb3cde3ccebc5decbe4fed9a6ffffcce5d8bdfddaecf2f2f2");
  
              var Pastel2 = colors("b3e2cdfdcdaccbd5e8f4cae4e6f5c9fff2aef1e2cccccccc");
  
              var Set1 = colors("e41a1c377eb84daf4a984ea3ff7f00ffff33a65628f781bf999999");
  
              var Set2 = colors("66c2a5fc8d628da0cbe78ac3a6d854ffd92fe5c494b3b3b3");
  
              var Set3 = colors("8dd3c7ffffb3bebadafb807280b1d3fdb462b3de69fccde5d9d9d9bc80bdccebc5ffed6f");
  
              var Tableau10 = colors("4e79a7f28e2ce1575976b7b259a14fedc949af7aa1ff9da79c755fbab0ab");
  
              function ramp(scheme) {
                  return rgbBasis(scheme[scheme.length - 1]);
              }
  
              var scheme = new Array(3).concat(
                      "d8b365f5f5f55ab4ac",
                      "a6611adfc27d80cdc1018571",
                      "a6611adfc27df5f5f580cdc1018571",
                      "8c510ad8b365f6e8c3c7eae55ab4ac01665e",
                      "8c510ad8b365f6e8c3f5f5f5c7eae55ab4ac01665e",
                      "8c510abf812ddfc27df6e8c3c7eae580cdc135978f01665e",
                      "8c510abf812ddfc27df6e8c3f5f5f5c7eae580cdc135978f01665e",
                      "5430058c510abf812ddfc27df6e8c3c7eae580cdc135978f01665e003c30",
                      "5430058c510abf812ddfc27df6e8c3f5f5f5c7eae580cdc135978f01665e003c30"
                      ).map(colors);
  
              var BrBG = ramp(scheme);
  
              var scheme$1 = new Array(3).concat(
                      "af8dc3f7f7f77fbf7b",
                      "7b3294c2a5cfa6dba0008837",
                      "7b3294c2a5cff7f7f7a6dba0008837",
                      "762a83af8dc3e7d4e8d9f0d37fbf7b1b7837",
                      "762a83af8dc3e7d4e8f7f7f7d9f0d37fbf7b1b7837",
                      "762a839970abc2a5cfe7d4e8d9f0d3a6dba05aae611b7837",
                      "762a839970abc2a5cfe7d4e8f7f7f7d9f0d3a6dba05aae611b7837",
                      "40004b762a839970abc2a5cfe7d4e8d9f0d3a6dba05aae611b783700441b",
                      "40004b762a839970abc2a5cfe7d4e8f7f7f7d9f0d3a6dba05aae611b783700441b"
                      ).map(colors);
  
              var PRGn = ramp(scheme$1);
  
              var scheme$2 = new Array(3).concat(
                      "e9a3c9f7f7f7a1d76a",
                      "d01c8bf1b6dab8e1864dac26",
                      "d01c8bf1b6daf7f7f7b8e1864dac26",
                      "c51b7de9a3c9fde0efe6f5d0a1d76a4d9221",
                      "c51b7de9a3c9fde0eff7f7f7e6f5d0a1d76a4d9221",
                      "c51b7dde77aef1b6dafde0efe6f5d0b8e1867fbc414d9221",
                      "c51b7dde77aef1b6dafde0eff7f7f7e6f5d0b8e1867fbc414d9221",
                      "8e0152c51b7dde77aef1b6dafde0efe6f5d0b8e1867fbc414d9221276419",
                      "8e0152c51b7dde77aef1b6dafde0eff7f7f7e6f5d0b8e1867fbc414d9221276419"
                      ).map(colors);
  
              var PiYG = ramp(scheme$2);
  
              var scheme$3 = new Array(3).concat(
                      "998ec3f7f7f7f1a340",
                      "5e3c99b2abd2fdb863e66101",
                      "5e3c99b2abd2f7f7f7fdb863e66101",
                      "542788998ec3d8daebfee0b6f1a340b35806",
                      "542788998ec3d8daebf7f7f7fee0b6f1a340b35806",
                      "5427888073acb2abd2d8daebfee0b6fdb863e08214b35806",
                      "5427888073acb2abd2d8daebf7f7f7fee0b6fdb863e08214b35806",
                      "2d004b5427888073acb2abd2d8daebfee0b6fdb863e08214b358067f3b08",
                      "2d004b5427888073acb2abd2d8daebf7f7f7fee0b6fdb863e08214b358067f3b08"
                      ).map(colors);
  
              var PuOr = ramp(scheme$3);
  
              var scheme$4 = new Array(3).concat(
                      "ef8a62f7f7f767a9cf",
                      "ca0020f4a58292c5de0571b0",
                      "ca0020f4a582f7f7f792c5de0571b0",
                      "b2182bef8a62fddbc7d1e5f067a9cf2166ac",
                      "b2182bef8a62fddbc7f7f7f7d1e5f067a9cf2166ac",
                      "b2182bd6604df4a582fddbc7d1e5f092c5de4393c32166ac",
                      "b2182bd6604df4a582fddbc7f7f7f7d1e5f092c5de4393c32166ac",
                      "67001fb2182bd6604df4a582fddbc7d1e5f092c5de4393c32166ac053061",
                      "67001fb2182bd6604df4a582fddbc7f7f7f7d1e5f092c5de4393c32166ac053061"
                      ).map(colors);
  
              var RdBu = ramp(scheme$4);
  
              var scheme$5 = new Array(3).concat(
                      "ef8a62ffffff999999",
                      "ca0020f4a582bababa404040",
                      "ca0020f4a582ffffffbababa404040",
                      "b2182bef8a62fddbc7e0e0e09999994d4d4d",
                      "b2182bef8a62fddbc7ffffffe0e0e09999994d4d4d",
                      "b2182bd6604df4a582fddbc7e0e0e0bababa8787874d4d4d",
                      "b2182bd6604df4a582fddbc7ffffffe0e0e0bababa8787874d4d4d",
                      "67001fb2182bd6604df4a582fddbc7e0e0e0bababa8787874d4d4d1a1a1a",
                      "67001fb2182bd6604df4a582fddbc7ffffffe0e0e0bababa8787874d4d4d1a1a1a"
                      ).map(colors);
  
              var RdGy = ramp(scheme$5);
  
              var scheme$6 = new Array(3).concat(
                      "fc8d59ffffbf91bfdb",
                      "d7191cfdae61abd9e92c7bb6",
                      "d7191cfdae61ffffbfabd9e92c7bb6",
                      "d73027fc8d59fee090e0f3f891bfdb4575b4",
                      "d73027fc8d59fee090ffffbfe0f3f891bfdb4575b4",
                      "d73027f46d43fdae61fee090e0f3f8abd9e974add14575b4",
                      "d73027f46d43fdae61fee090ffffbfe0f3f8abd9e974add14575b4",
                      "a50026d73027f46d43fdae61fee090e0f3f8abd9e974add14575b4313695",
                      "a50026d73027f46d43fdae61fee090ffffbfe0f3f8abd9e974add14575b4313695"
                      ).map(colors);
  
              var RdYlBu = ramp(scheme$6);
  
              var scheme$7 = new Array(3).concat(
                      "fc8d59ffffbf91cf60",
                      "d7191cfdae61a6d96a1a9641",
                      "d7191cfdae61ffffbfa6d96a1a9641",
                      "d73027fc8d59fee08bd9ef8b91cf601a9850",
                      "d73027fc8d59fee08bffffbfd9ef8b91cf601a9850",
                      "d73027f46d43fdae61fee08bd9ef8ba6d96a66bd631a9850",
                      "d73027f46d43fdae61fee08bffffbfd9ef8ba6d96a66bd631a9850",
                      "a50026d73027f46d43fdae61fee08bd9ef8ba6d96a66bd631a9850006837",
                      "a50026d73027f46d43fdae61fee08bffffbfd9ef8ba6d96a66bd631a9850006837"
                      ).map(colors);
  
              var RdYlGn = ramp(scheme$7);
  
              var scheme$8 = new Array(3).concat(
                      "fc8d59ffffbf99d594",
                      "d7191cfdae61abdda42b83ba",
                      "d7191cfdae61ffffbfabdda42b83ba",
                      "d53e4ffc8d59fee08be6f59899d5943288bd",
                      "d53e4ffc8d59fee08bffffbfe6f59899d5943288bd",
                      "d53e4ff46d43fdae61fee08be6f598abdda466c2a53288bd",
                      "d53e4ff46d43fdae61fee08bffffbfe6f598abdda466c2a53288bd",
                      "9e0142d53e4ff46d43fdae61fee08be6f598abdda466c2a53288bd5e4fa2",
                      "9e0142d53e4ff46d43fdae61fee08bffffbfe6f598abdda466c2a53288bd5e4fa2"
                      ).map(colors);
  
              var Spectral = ramp(scheme$8);
  
              var scheme$9 = new Array(3).concat(
                      "e5f5f999d8c92ca25f",
                      "edf8fbb2e2e266c2a4238b45",
                      "edf8fbb2e2e266c2a42ca25f006d2c",
                      "edf8fbccece699d8c966c2a42ca25f006d2c",
                      "edf8fbccece699d8c966c2a441ae76238b45005824",
                      "f7fcfde5f5f9ccece699d8c966c2a441ae76238b45005824",
                      "f7fcfde5f5f9ccece699d8c966c2a441ae76238b45006d2c00441b"
                      ).map(colors);
  
              var BuGn = ramp(scheme$9);
  
              var scheme$a = new Array(3).concat(
                      "e0ecf49ebcda8856a7",
                      "edf8fbb3cde38c96c688419d",
                      "edf8fbb3cde38c96c68856a7810f7c",
                      "edf8fbbfd3e69ebcda8c96c68856a7810f7c",
                      "edf8fbbfd3e69ebcda8c96c68c6bb188419d6e016b",
                      "f7fcfde0ecf4bfd3e69ebcda8c96c68c6bb188419d6e016b",
                      "f7fcfde0ecf4bfd3e69ebcda8c96c68c6bb188419d810f7c4d004b"
                      ).map(colors);
  
              var BuPu = ramp(scheme$a);
  
              var scheme$b = new Array(3).concat(
                      "e0f3dba8ddb543a2ca",
                      "f0f9e8bae4bc7bccc42b8cbe",
                      "f0f9e8bae4bc7bccc443a2ca0868ac",
                      "f0f9e8ccebc5a8ddb57bccc443a2ca0868ac",
                      "f0f9e8ccebc5a8ddb57bccc44eb3d32b8cbe08589e",
                      "f7fcf0e0f3dbccebc5a8ddb57bccc44eb3d32b8cbe08589e",
                      "f7fcf0e0f3dbccebc5a8ddb57bccc44eb3d32b8cbe0868ac084081"
                      ).map(colors);
  
              var GnBu = ramp(scheme$b);
  
              var scheme$c = new Array(3).concat(
                      "fee8c8fdbb84e34a33",
                      "fef0d9fdcc8afc8d59d7301f",
                      "fef0d9fdcc8afc8d59e34a33b30000",
                      "fef0d9fdd49efdbb84fc8d59e34a33b30000",
                      "fef0d9fdd49efdbb84fc8d59ef6548d7301f990000",
                      "fff7ecfee8c8fdd49efdbb84fc8d59ef6548d7301f990000",
                      "fff7ecfee8c8fdd49efdbb84fc8d59ef6548d7301fb300007f0000"
                      ).map(colors);
  
              var OrRd = ramp(scheme$c);
  
              var scheme$d = new Array(3).concat(
                      "ece2f0a6bddb1c9099",
                      "f6eff7bdc9e167a9cf02818a",
                      "f6eff7bdc9e167a9cf1c9099016c59",
                      "f6eff7d0d1e6a6bddb67a9cf1c9099016c59",
                      "f6eff7d0d1e6a6bddb67a9cf3690c002818a016450",
                      "fff7fbece2f0d0d1e6a6bddb67a9cf3690c002818a016450",
                      "fff7fbece2f0d0d1e6a6bddb67a9cf3690c002818a016c59014636"
                      ).map(colors);
  
              var PuBuGn = ramp(scheme$d);
  
              var scheme$e = new Array(3).concat(
                      "ece7f2a6bddb2b8cbe",
                      "f1eef6bdc9e174a9cf0570b0",
                      "f1eef6bdc9e174a9cf2b8cbe045a8d",
                      "f1eef6d0d1e6a6bddb74a9cf2b8cbe045a8d",
                      "f1eef6d0d1e6a6bddb74a9cf3690c00570b0034e7b",
                      "fff7fbece7f2d0d1e6a6bddb74a9cf3690c00570b0034e7b",
                      "fff7fbece7f2d0d1e6a6bddb74a9cf3690c00570b0045a8d023858"
                      ).map(colors);
  
              var PuBu = ramp(scheme$e);
  
              var scheme$f = new Array(3).concat(
                      "e7e1efc994c7dd1c77",
                      "f1eef6d7b5d8df65b0ce1256",
                      "f1eef6d7b5d8df65b0dd1c77980043",
                      "f1eef6d4b9dac994c7df65b0dd1c77980043",
                      "f1eef6d4b9dac994c7df65b0e7298ace125691003f",
                      "f7f4f9e7e1efd4b9dac994c7df65b0e7298ace125691003f",
                      "f7f4f9e7e1efd4b9dac994c7df65b0e7298ace125698004367001f"
                      ).map(colors);
  
              var PuRd = ramp(scheme$f);
  
              var scheme$g = new Array(3).concat(
                      "fde0ddfa9fb5c51b8a",
                      "feebe2fbb4b9f768a1ae017e",
                      "feebe2fbb4b9f768a1c51b8a7a0177",
                      "feebe2fcc5c0fa9fb5f768a1c51b8a7a0177",
                      "feebe2fcc5c0fa9fb5f768a1dd3497ae017e7a0177",
                      "fff7f3fde0ddfcc5c0fa9fb5f768a1dd3497ae017e7a0177",
                      "fff7f3fde0ddfcc5c0fa9fb5f768a1dd3497ae017e7a017749006a"
                      ).map(colors);
  
              var RdPu = ramp(scheme$g);
  
              var scheme$h = new Array(3).concat(
                      "edf8b17fcdbb2c7fb8",
                      "ffffcca1dab441b6c4225ea8",
                      "ffffcca1dab441b6c42c7fb8253494",
                      "ffffccc7e9b47fcdbb41b6c42c7fb8253494",
                      "ffffccc7e9b47fcdbb41b6c41d91c0225ea80c2c84",
                      "ffffd9edf8b1c7e9b47fcdbb41b6c41d91c0225ea80c2c84",
                      "ffffd9edf8b1c7e9b47fcdbb41b6c41d91c0225ea8253494081d58"
                      ).map(colors);
  
              var YlGnBu = ramp(scheme$h);
  
              var scheme$i = new Array(3).concat(
                      "f7fcb9addd8e31a354",
                      "ffffccc2e69978c679238443",
                      "ffffccc2e69978c67931a354006837",
                      "ffffccd9f0a3addd8e78c67931a354006837",
                      "ffffccd9f0a3addd8e78c67941ab5d238443005a32",
                      "ffffe5f7fcb9d9f0a3addd8e78c67941ab5d238443005a32",
                      "ffffe5f7fcb9d9f0a3addd8e78c67941ab5d238443006837004529"
                      ).map(colors);
  
              var YlGn = ramp(scheme$i);
  
              var scheme$j = new Array(3).concat(
                      "fff7bcfec44fd95f0e",
                      "ffffd4fed98efe9929cc4c02",
                      "ffffd4fed98efe9929d95f0e993404",
                      "ffffd4fee391fec44ffe9929d95f0e993404",
                      "ffffd4fee391fec44ffe9929ec7014cc4c028c2d04",
                      "ffffe5fff7bcfee391fec44ffe9929ec7014cc4c028c2d04",
                      "ffffe5fff7bcfee391fec44ffe9929ec7014cc4c02993404662506"
                      ).map(colors);
  
              var YlOrBr = ramp(scheme$j);
  
              var scheme$k = new Array(3).concat(
                      "ffeda0feb24cf03b20",
                      "ffffb2fecc5cfd8d3ce31a1c",
                      "ffffb2fecc5cfd8d3cf03b20bd0026",
                      "ffffb2fed976feb24cfd8d3cf03b20bd0026",
                      "ffffb2fed976feb24cfd8d3cfc4e2ae31a1cb10026",
                      "ffffccffeda0fed976feb24cfd8d3cfc4e2ae31a1cb10026",
                      "ffffccffeda0fed976feb24cfd8d3cfc4e2ae31a1cbd0026800026"
                      ).map(colors);
  
              var YlOrRd = ramp(scheme$k);
  
              var scheme$l = new Array(3).concat(
                      "deebf79ecae13182bd",
                      "eff3ffbdd7e76baed62171b5",
                      "eff3ffbdd7e76baed63182bd08519c",
                      "eff3ffc6dbef9ecae16baed63182bd08519c",
                      "eff3ffc6dbef9ecae16baed64292c62171b5084594",
                      "f7fbffdeebf7c6dbef9ecae16baed64292c62171b5084594",
                      "f7fbffdeebf7c6dbef9ecae16baed64292c62171b508519c08306b"
                      ).map(colors);
  
              var Blues = ramp(scheme$l);
  
              var scheme$m = new Array(3).concat(
                      "e5f5e0a1d99b31a354",
                      "edf8e9bae4b374c476238b45",
                      "edf8e9bae4b374c47631a354006d2c",
                      "edf8e9c7e9c0a1d99b74c47631a354006d2c",
                      "edf8e9c7e9c0a1d99b74c47641ab5d238b45005a32",
                      "f7fcf5e5f5e0c7e9c0a1d99b74c47641ab5d238b45005a32",
                      "f7fcf5e5f5e0c7e9c0a1d99b74c47641ab5d238b45006d2c00441b"
                      ).map(colors);
  
              var Greens = ramp(scheme$m);
  
              var scheme$n = new Array(3).concat(
                      "f0f0f0bdbdbd636363",
                      "f7f7f7cccccc969696525252",
                      "f7f7f7cccccc969696636363252525",
                      "f7f7f7d9d9d9bdbdbd969696636363252525",
                      "f7f7f7d9d9d9bdbdbd969696737373525252252525",
                      "fffffff0f0f0d9d9d9bdbdbd969696737373525252252525",
                      "fffffff0f0f0d9d9d9bdbdbd969696737373525252252525000000"
                      ).map(colors);
  
              var Greys = ramp(scheme$n);
  
              var scheme$o = new Array(3).concat(
                      "efedf5bcbddc756bb1",
                      "f2f0f7cbc9e29e9ac86a51a3",
                      "f2f0f7cbc9e29e9ac8756bb154278f",
                      "f2f0f7dadaebbcbddc9e9ac8756bb154278f",
                      "f2f0f7dadaebbcbddc9e9ac8807dba6a51a34a1486",
                      "fcfbfdefedf5dadaebbcbddc9e9ac8807dba6a51a34a1486",
                      "fcfbfdefedf5dadaebbcbddc9e9ac8807dba6a51a354278f3f007d"
                      ).map(colors);
  
              var Purples = ramp(scheme$o);
  
              var scheme$p = new Array(3).concat(
                      "fee0d2fc9272de2d26",
                      "fee5d9fcae91fb6a4acb181d",
                      "fee5d9fcae91fb6a4ade2d26a50f15",
                      "fee5d9fcbba1fc9272fb6a4ade2d26a50f15",
                      "fee5d9fcbba1fc9272fb6a4aef3b2ccb181d99000d",
                      "fff5f0fee0d2fcbba1fc9272fb6a4aef3b2ccb181d99000d",
                      "fff5f0fee0d2fcbba1fc9272fb6a4aef3b2ccb181da50f1567000d"
                      ).map(colors);
  
              var Reds = ramp(scheme$p);
  
              var scheme$q = new Array(3).concat(
                      "fee6cefdae6be6550d",
                      "feeddefdbe85fd8d3cd94701",
                      "feeddefdbe85fd8d3ce6550da63603",
                      "feeddefdd0a2fdae6bfd8d3ce6550da63603",
                      "feeddefdd0a2fdae6bfd8d3cf16913d948018c2d04",
                      "fff5ebfee6cefdd0a2fdae6bfd8d3cf16913d948018c2d04",
                      "fff5ebfee6cefdd0a2fdae6bfd8d3cf16913d94801a636037f2704"
                      ).map(colors);
  
              var Oranges = ramp(scheme$q);
  
              function cividis(t) {
                  t = Math.max(0, Math.min(1, t));
                  return "rgb("
                          + Math.max(0, Math.min(255, Math.round(-4.54 - t * (35.34 - t * (2381.73 - t * (6402.7 - t * (7024.72 - t * 2710.57))))))) + ", "
                          + Math.max(0, Math.min(255, Math.round(32.49 + t * (170.73 + t * (52.82 - t * (131.46 - t * (176.58 - t * 67.37))))))) + ", "
                          + Math.max(0, Math.min(255, Math.round(81.24 + t * (442.36 - t * (2482.43 - t * (6167.24 - t * (6614.94 - t * 2475.67)))))))
                          + ")";
              }
  
              var cubehelix$3 = cubehelixLong(cubehelix(300, 0.5, 0.0), cubehelix(-240, 0.5, 1.0));
  
              var warm = cubehelixLong(cubehelix(-100, 0.75, 0.35), cubehelix(80, 1.50, 0.8));
  
              var cool = cubehelixLong(cubehelix(260, 0.75, 0.35), cubehelix(80, 1.50, 0.8));
  
              var c = cubehelix();
  
              function rainbow(t) {
                  if (t < 0 || t > 1)
                      t -= Math.floor(t);
                  var ts = Math.abs(t - 0.5);
                  c.h = 360 * t - 100;
                  c.s = 1.5 - 1.5 * ts;
                  c.l = 0.8 - 0.9 * ts;
                  return c + "";
              }
  
              var c$1 = rgb(),
                      pi_1_3 = Math.PI / 3,
                      pi_2_3 = Math.PI * 2 / 3;
  
              function sinebow(t) {
                  var x;
                  t = (0.5 - t) * Math.PI;
                  c$1.r = 255 * (x = Math.sin(t)) * x;
                  c$1.g = 255 * (x = Math.sin(t + pi_1_3)) * x;
                  c$1.b = 255 * (x = Math.sin(t + pi_2_3)) * x;
                  return c$1 + "";
              }
  
              function turbo(t) {
                  t = Math.max(0, Math.min(1, t));
                  return "rgb("
                          + Math.max(0, Math.min(255, Math.round(34.61 + t * (1172.33 - t * (10793.56 - t * (33300.12 - t * (38394.49 - t * 14825.05))))))) + ", "
                          + Math.max(0, Math.min(255, Math.round(23.31 + t * (557.33 + t * (1225.33 - t * (3574.96 - t * (1073.77 + t * 707.56))))))) + ", "
                          + Math.max(0, Math.min(255, Math.round(27.2 + t * (3211.1 - t * (15327.97 - t * (27814 - t * (22569.18 - t * 6838.66)))))))
                          + ")";
              }
  
              function ramp$1(range) {
                  var n = range.length;
                  return function (t) {
                      return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
                  };
              }
  
              var viridis = ramp$1(colors("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"));
  
              var magma = ramp$1(colors("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"));
  
              var inferno = ramp$1(colors("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"));
  
              var plasma = ramp$1(colors("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"));
  
              function constant$b(x) {
                  return function constant() {
                      return x;
                  };
              }
  
              var abs$1 = Math.abs;
              var atan2$1 = Math.atan2;
              var cos$2 = Math.cos;
              var max$2 = Math.max;
              var min$1 = Math.min;
              var sin$2 = Math.sin;
              var sqrt$2 = Math.sqrt;
  
              var epsilon$3 = 1e-12;
              var pi$4 = Math.PI;
              var halfPi$3 = pi$4 / 2;
              var tau$4 = 2 * pi$4;
  
              function acos$1(x) {
                  return x > 1 ? 0 : x < -1 ? pi$4 : Math.acos(x);
              }
  
              function asin$1(x) {
                  return x >= 1 ? halfPi$3 : x <= -1 ? -halfPi$3 : Math.asin(x);
              }
  
              function arcInnerRadius(d) {
                  return d.innerRadius;
              }
  
              function arcOuterRadius(d) {
                  return d.outerRadius;
              }
  
              function arcStartAngle(d) {
                  return d.startAngle;
              }
  
              function arcEndAngle(d) {
                  return d.endAngle;
              }
  
              function arcPadAngle(d) {
                  return d && d.padAngle; // Note: optional!
              }
  
              function intersect(x0, y0, x1, y1, x2, y2, x3, y3) {
                  var x10 = x1 - x0, y10 = y1 - y0,
                          x32 = x3 - x2, y32 = y3 - y2,
                          t = y32 * x10 - x32 * y10;
                  if (t * t < epsilon$3)
                      return;
                  t = (x32 * (y0 - y2) - y32 * (x0 - x2)) / t;
                  return [x0 + t * x10, y0 + t * y10];
              }
  
  // Compute perpendicular offset line of length rc.
  // http://mathworld.wolfram.com/Circle-LineIntersection.html
              function cornerTangents(x0, y0, x1, y1, r1, rc, cw) {
                  var x01 = x0 - x1,
                          y01 = y0 - y1,
                          lo = (cw ? rc : -rc) / sqrt$2(x01 * x01 + y01 * y01),
                          ox = lo * y01,
                          oy = -lo * x01,
                          x11 = x0 + ox,
                          y11 = y0 + oy,
                          x10 = x1 + ox,
                          y10 = y1 + oy,
                          x00 = (x11 + x10) / 2,
                          y00 = (y11 + y10) / 2,
                          dx = x10 - x11,
                          dy = y10 - y11,
                          d2 = dx * dx + dy * dy,
                          r = r1 - rc,
                          D = x11 * y10 - x10 * y11,
                          d = (dy < 0 ? -1 : 1) * sqrt$2(max$2(0, r * r * d2 - D * D)),
                          cx0 = (D * dy - dx * d) / d2,
                          cy0 = (-D * dx - dy * d) / d2,
                          cx1 = (D * dy + dx * d) / d2,
                          cy1 = (-D * dx + dy * d) / d2,
                          dx0 = cx0 - x00,
                          dy0 = cy0 - y00,
                          dx1 = cx1 - x00,
                          dy1 = cy1 - y00;
  
                  // Pick the closer of the two intersection points.
                  // TODO Is there a faster way to determine which intersection to use?
                  if (dx0 * dx0 + dy0 * dy0 > dx1 * dx1 + dy1 * dy1)
                      cx0 = cx1, cy0 = cy1;
  
                  return {
                      cx: cx0,
                      cy: cy0,
                      x01: -ox,
                      y01: -oy,
                      x11: cx0 * (r1 / r - 1),
                      y11: cy0 * (r1 / r - 1)
                  };
              }
  
              function arc() {
                  var innerRadius = arcInnerRadius,
                          outerRadius = arcOuterRadius,
                          cornerRadius = constant$b(0),
                          padRadius = null,
                          startAngle = arcStartAngle,
                          endAngle = arcEndAngle,
                          padAngle = arcPadAngle,
                          context = null;
  
                  function arc() {
                      var buffer,
                              r,
                              r0 = +innerRadius.apply(this, arguments),
                              r1 = +outerRadius.apply(this, arguments),
                              a0 = startAngle.apply(this, arguments) - halfPi$3,
                              a1 = endAngle.apply(this, arguments) - halfPi$3,
                              da = abs$1(a1 - a0),
                              cw = a1 > a0;
  
                      if (!context)
                          context = buffer = path();
  
                      // Ensure that the outer radius is always larger than the inner radius.
                      if (r1 < r0)
                          r = r1, r1 = r0, r0 = r;
  
                      // Is it a point?
                      if (!(r1 > epsilon$3))
                          context.moveTo(0, 0);
  
                      // Or is it a circle or annulus?
                      else if (da > tau$4 - epsilon$3) {
                          context.moveTo(r1 * cos$2(a0), r1 * sin$2(a0));
                          context.arc(0, 0, r1, a0, a1, !cw);
                          if (r0 > epsilon$3) {
                              context.moveTo(r0 * cos$2(a1), r0 * sin$2(a1));
                              context.arc(0, 0, r0, a1, a0, cw);
                          }
                      }
  
                      // Or is it a circular or annular sector?
                      else {
                          var a01 = a0,
                                  a11 = a1,
                                  a00 = a0,
                                  a10 = a1,
                                  da0 = da,
                                  da1 = da,
                                  ap = padAngle.apply(this, arguments) / 2,
                                  rp = (ap > epsilon$3) && (padRadius ? +padRadius.apply(this, arguments) : sqrt$2(r0 * r0 + r1 * r1)),
                                  rc = min$1(abs$1(r1 - r0) / 2, +cornerRadius.apply(this, arguments)),
                                  rc0 = rc,
                                  rc1 = rc,
                                  t0,
                                  t1;
  
                          // Apply padding? Note that since r1 ≥ r0, da1 ≥ da0.
                          if (rp > epsilon$3) {
                              var p0 = asin$1(rp / r0 * sin$2(ap)),
                                      p1 = asin$1(rp / r1 * sin$2(ap));
                              if ((da0 -= p0 * 2) > epsilon$3)
                                  p0 *= (cw ? 1 : -1), a00 += p0, a10 -= p0;
                              else
                                  da0 = 0, a00 = a10 = (a0 + a1) / 2;
                              if ((da1 -= p1 * 2) > epsilon$3)
                                  p1 *= (cw ? 1 : -1), a01 += p1, a11 -= p1;
                              else
                                  da1 = 0, a01 = a11 = (a0 + a1) / 2;
                          }
  
                          var x01 = r1 * cos$2(a01),
                                  y01 = r1 * sin$2(a01),
                                  x10 = r0 * cos$2(a10),
                                  y10 = r0 * sin$2(a10);
  
                          // Apply rounded corners?
                          if (rc > epsilon$3) {
                              var x11 = r1 * cos$2(a11),
                                      y11 = r1 * sin$2(a11),
                                      x00 = r0 * cos$2(a00),
                                      y00 = r0 * sin$2(a00),
                                      oc;
  
                              // Restrict the corner radius according to the sector angle.
                              if (da < pi$4 && (oc = intersect(x01, y01, x00, y00, x11, y11, x10, y10))) {
                                  var ax = x01 - oc[0],
                                          ay = y01 - oc[1],
                                          bx = x11 - oc[0],
                                          by = y11 - oc[1],
                                          kc = 1 / sin$2(acos$1((ax * bx + ay * by) / (sqrt$2(ax * ax + ay * ay) * sqrt$2(bx * bx + by * by))) / 2),
                                          lc = sqrt$2(oc[0] * oc[0] + oc[1] * oc[1]);
                                  rc0 = min$1(rc, (r0 - lc) / (kc - 1));
                                  rc1 = min$1(rc, (r1 - lc) / (kc + 1));
                              }
                          }
  
                          // Is the sector collapsed to a line?
                          if (!(da1 > epsilon$3))
                              context.moveTo(x01, y01);
  
                          // Does the sector’s outer ring have rounded corners?
                          else if (rc1 > epsilon$3) {
                              t0 = cornerTangents(x00, y00, x01, y01, r1, rc1, cw);
                              t1 = cornerTangents(x11, y11, x10, y10, r1, rc1, cw);
  
                              context.moveTo(t0.cx + t0.x01, t0.cy + t0.y01);
  
                              // Have the corners merged?
                              if (rc1 < rc)
                                  context.arc(t0.cx, t0.cy, rc1, atan2$1(t0.y01, t0.x01), atan2$1(t1.y01, t1.x01), !cw);
  
                              // Otherwise, draw the two corners and the ring.
                              else {
                                  context.arc(t0.cx, t0.cy, rc1, atan2$1(t0.y01, t0.x01), atan2$1(t0.y11, t0.x11), !cw);
                                  context.arc(0, 0, r1, atan2$1(t0.cy + t0.y11, t0.cx + t0.x11), atan2$1(t1.cy + t1.y11, t1.cx + t1.x11), !cw);
                                  context.arc(t1.cx, t1.cy, rc1, atan2$1(t1.y11, t1.x11), atan2$1(t1.y01, t1.x01), !cw);
                              }
                          }
  
                          // Or is the outer ring just a circular arc?
                          else
                              context.moveTo(x01, y01), context.arc(0, 0, r1, a01, a11, !cw);
  
                          // Is there no inner ring, and it’s a circular sector?
                          // Or perhaps it’s an annular sector collapsed due to padding?
                          if (!(r0 > epsilon$3) || !(da0 > epsilon$3))
                              context.lineTo(x10, y10);
  
                          // Does the sector’s inner ring (or point) have rounded corners?
                          else if (rc0 > epsilon$3) {
                              t0 = cornerTangents(x10, y10, x11, y11, r0, -rc0, cw);
                              t1 = cornerTangents(x01, y01, x00, y00, r0, -rc0, cw);
  
                              context.lineTo(t0.cx + t0.x01, t0.cy + t0.y01);
  
                              // Have the corners merged?
                              if (rc0 < rc)
                                  context.arc(t0.cx, t0.cy, rc0, atan2$1(t0.y01, t0.x01), atan2$1(t1.y01, t1.x01), !cw);
  
                              // Otherwise, draw the two corners and the ring.
                              else {
                                  context.arc(t0.cx, t0.cy, rc0, atan2$1(t0.y01, t0.x01), atan2$1(t0.y11, t0.x11), !cw);
                                  context.arc(0, 0, r0, atan2$1(t0.cy + t0.y11, t0.cx + t0.x11), atan2$1(t1.cy + t1.y11, t1.cx + t1.x11), cw);
                                  context.arc(t1.cx, t1.cy, rc0, atan2$1(t1.y11, t1.x11), atan2$1(t1.y01, t1.x01), !cw);
                              }
                          }
  
                          // Or is the inner ring just a circular arc?
                          else
                              context.arc(0, 0, r0, a10, a00, cw);
                      }
  
                      context.closePath();
  
                      if (buffer)
                          return context = null, buffer + "" || null;
                  }
  
                  arc.centroid = function () {
                      var r = (+innerRadius.apply(this, arguments) + +outerRadius.apply(this, arguments)) / 2,
                              a = (+startAngle.apply(this, arguments) + +endAngle.apply(this, arguments)) / 2 - pi$4 / 2;
                      return [cos$2(a) * r, sin$2(a) * r];
                  };
  
                  arc.innerRadius = function (_) {
                      return arguments.length ? (innerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : innerRadius;
                  };
  
                  arc.outerRadius = function (_) {
                      return arguments.length ? (outerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : outerRadius;
                  };
  
                  arc.cornerRadius = function (_) {
                      return arguments.length ? (cornerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : cornerRadius;
                  };
  
                  arc.padRadius = function (_) {
                      return arguments.length ? (padRadius = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), arc) : padRadius;
                  };
  
                  arc.startAngle = function (_) {
                      return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : startAngle;
                  };
  
                  arc.endAngle = function (_) {
                      return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : endAngle;
                  };
  
                  arc.padAngle = function (_) {
                      return arguments.length ? (padAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : padAngle;
                  };
  
                  arc.context = function (_) {
                      return arguments.length ? ((context = _ == null ? null : _), arc) : context;
                  };
  
                  return arc;
              }
  
              function Linear(context) {
                  this._context = context;
              }
  
              Linear.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2; // proceed
                          default:
                              this._context.lineTo(x, y);
                              break;
                      }
                  }
              };
  
              function curveLinear(context) {
                  return new Linear(context);
              }
  
              function x$3(p) {
                  return p[0];
              }
  
              function y$3(p) {
                  return p[1];
              }
  
              function line() {
                  var x = x$3,
                          y = y$3,
                          defined = constant$b(true),
                          context = null,
                          curve = curveLinear,
                          output = null;
  
                  function line(data) {
                      var i,
                              n = data.length,
                              d,
                              defined0 = false,
                              buffer;
  
                      if (context == null)
                          output = curve(buffer = path());
  
                      for (i = 0; i <= n; ++i) {
                          if (!(i < n && defined(d = data[i], i, data)) === defined0) {
                              if (defined0 = !defined0)
                                  output.lineStart();
                              else
                                  output.lineEnd();
                          }
                          if (defined0)
                              output.point(+x(d, i, data), +y(d, i, data));
                      }
  
                      if (buffer)
                          return output = null, buffer + "" || null;
                  }
  
                  line.x = function (_) {
                      return arguments.length ? (x = typeof _ === "function" ? _ : constant$b(+_), line) : x;
                  };
  
                  line.y = function (_) {
                      return arguments.length ? (y = typeof _ === "function" ? _ : constant$b(+_), line) : y;
                  };
  
                  line.defined = function (_) {
                      return arguments.length ? (defined = typeof _ === "function" ? _ : constant$b(!!_), line) : defined;
                  };
  
                  line.curve = function (_) {
                      return arguments.length ? (curve = _, context != null && (output = curve(context)), line) : curve;
                  };
  
                  line.context = function (_) {
                      return arguments.length ? (_ == null ? context = output = null : output = curve(context = _), line) : context;
                  };
  
                  return line;
              }
  
              function area$3() {
                  var x0 = x$3,
                          x1 = null,
                          y0 = constant$b(0),
                          y1 = y$3,
                          defined = constant$b(true),
                          context = null,
                          curve = curveLinear,
                          output = null;
  
                  function area(data) {
                      var i,
                              j,
                              k,
                              n = data.length,
                              d,
                              defined0 = false,
                              buffer,
                              x0z = new Array(n),
                              y0z = new Array(n);
  
                      if (context == null)
                          output = curve(buffer = path());
  
                      for (i = 0; i <= n; ++i) {
                          if (!(i < n && defined(d = data[i], i, data)) === defined0) {
                              if (defined0 = !defined0) {
                                  j = i;
                                  output.areaStart();
                                  output.lineStart();
                              } else {
                                  output.lineEnd();
                                  output.lineStart();
                                  for (k = i - 1; k >= j; --k) {
                                      output.point(x0z[k], y0z[k]);
                                  }
                                  output.lineEnd();
                                  output.areaEnd();
                              }
                          }
                          if (defined0) {
                              x0z[i] = +x0(d, i, data), y0z[i] = +y0(d, i, data);
                              output.point(x1 ? +x1(d, i, data) : x0z[i], y1 ? +y1(d, i, data) : y0z[i]);
                          }
                      }
  
                      if (buffer)
                          return output = null, buffer + "" || null;
                  }
  
                  function arealine() {
                      return line().defined(defined).curve(curve).context(context);
                  }
  
                  area.x = function (_) {
                      return arguments.length ? (x0 = typeof _ === "function" ? _ : constant$b(+_), x1 = null, area) : x0;
                  };
  
                  area.x0 = function (_) {
                      return arguments.length ? (x0 = typeof _ === "function" ? _ : constant$b(+_), area) : x0;
                  };
  
                  area.x1 = function (_) {
                      return arguments.length ? (x1 = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), area) : x1;
                  };
  
                  area.y = function (_) {
                      return arguments.length ? (y0 = typeof _ === "function" ? _ : constant$b(+_), y1 = null, area) : y0;
                  };
  
                  area.y0 = function (_) {
                      return arguments.length ? (y0 = typeof _ === "function" ? _ : constant$b(+_), area) : y0;
                  };
  
                  area.y1 = function (_) {
                      return arguments.length ? (y1 = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), area) : y1;
                  };
  
                  area.lineX0 =
                          area.lineY0 = function () {
                              return arealine().x(x0).y(y0);
                          };
  
                  area.lineY1 = function () {
                      return arealine().x(x0).y(y1);
                  };
  
                  area.lineX1 = function () {
                      return arealine().x(x1).y(y0);
                  };
  
                  area.defined = function (_) {
                      return arguments.length ? (defined = typeof _ === "function" ? _ : constant$b(!!_), area) : defined;
                  };
  
                  area.curve = function (_) {
                      return arguments.length ? (curve = _, context != null && (output = curve(context)), area) : curve;
                  };
  
                  area.context = function (_) {
                      return arguments.length ? (_ == null ? context = output = null : output = curve(context = _), area) : context;
                  };
  
                  return area;
              }
  
              function descending$1(a, b) {
                  return b < a ? -1 : b > a ? 1 : b >= a ? 0 : NaN;
              }
  
              function identity$8(d) {
                  return d;
              }
  
              function pie() {
                  var value = identity$8,
                          sortValues = descending$1,
                          sort = null,
                          startAngle = constant$b(0),
                          endAngle = constant$b(tau$4),
                          padAngle = constant$b(0);
  
                  function pie(data) {
                      var i,
                              n = data.length,
                              j,
                              k,
                              sum = 0,
                              index = new Array(n),
                              arcs = new Array(n),
                              a0 = +startAngle.apply(this, arguments),
                              da = Math.min(tau$4, Math.max(-tau$4, endAngle.apply(this, arguments) - a0)),
                              a1,
                              p = Math.min(Math.abs(da) / n, padAngle.apply(this, arguments)),
                              pa = p * (da < 0 ? -1 : 1),
                              v;
  
                      for (i = 0; i < n; ++i) {
                          if ((v = arcs[index[i] = i] = +value(data[i], i, data)) > 0) {
                              sum += v;
                          }
                      }
  
                      // Optionally sort the arcs by previously-computed values or by data.
                      if (sortValues != null)
                          index.sort(function (i, j) {
                              return sortValues(arcs[i], arcs[j]);
                          });
                      else if (sort != null)
                          index.sort(function (i, j) {
                              return sort(data[i], data[j]);
                          });
  
                      // Compute the arcs! They are stored in the original data's order.
                      for (i = 0, k = sum ? (da - n * pa) / sum : 0; i < n; ++i, a0 = a1) {
                          j = index[i], v = arcs[j], a1 = a0 + (v > 0 ? v * k : 0) + pa, arcs[j] = {
                              data: data[j],
                              index: i,
                              value: v,
                              startAngle: a0,
                              endAngle: a1,
                              padAngle: p
                          };
                      }
  
                      return arcs;
                  }
  
                  pie.value = function (_) {
                      return arguments.length ? (value = typeof _ === "function" ? _ : constant$b(+_), pie) : value;
                  };
  
                  pie.sortValues = function (_) {
                      return arguments.length ? (sortValues = _, sort = null, pie) : sortValues;
                  };
  
                  pie.sort = function (_) {
                      return arguments.length ? (sort = _, sortValues = null, pie) : sort;
                  };
  
                  pie.startAngle = function (_) {
                      return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : startAngle;
                  };
  
                  pie.endAngle = function (_) {
                      return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : endAngle;
                  };
  
                  pie.padAngle = function (_) {
                      return arguments.length ? (padAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : padAngle;
                  };
  
                  return pie;
              }
  
              var curveRadialLinear = curveRadial(curveLinear);
  
              function Radial(curve) {
                  this._curve = curve;
              }
  
              Radial.prototype = {
                  areaStart: function () {
                      this._curve.areaStart();
                  },
                  areaEnd: function () {
                      this._curve.areaEnd();
                  },
                  lineStart: function () {
                      this._curve.lineStart();
                  },
                  lineEnd: function () {
                      this._curve.lineEnd();
                  },
                  point: function (a, r) {
                      this._curve.point(r * Math.sin(a), r * -Math.cos(a));
                  }
              };
  
              function curveRadial(curve) {
  
                  function radial(context) {
                      return new Radial(curve(context));
                  }
  
                  radial._curve = curve;
  
                  return radial;
              }
  
              function lineRadial(l) {
                  var c = l.curve;
  
                  l.angle = l.x, delete l.x;
                  l.radius = l.y, delete l.y;
  
                  l.curve = function (_) {
                      return arguments.length ? c(curveRadial(_)) : c()._curve;
                  };
  
                  return l;
              }
  
              function lineRadial$1() {
                  return lineRadial(line().curve(curveRadialLinear));
              }
  
              function areaRadial() {
                  var a = area$3().curve(curveRadialLinear),
                          c = a.curve,
                          x0 = a.lineX0,
                          x1 = a.lineX1,
                          y0 = a.lineY0,
                          y1 = a.lineY1;
  
                  a.angle = a.x, delete a.x;
                  a.startAngle = a.x0, delete a.x0;
                  a.endAngle = a.x1, delete a.x1;
                  a.radius = a.y, delete a.y;
                  a.innerRadius = a.y0, delete a.y0;
                  a.outerRadius = a.y1, delete a.y1;
                  a.lineStartAngle = function () {
                      return lineRadial(x0());
                  }, delete a.lineX0;
                  a.lineEndAngle = function () {
                      return lineRadial(x1());
                  }, delete a.lineX1;
                  a.lineInnerRadius = function () {
                      return lineRadial(y0());
                  }, delete a.lineY0;
                  a.lineOuterRadius = function () {
                      return lineRadial(y1());
                  }, delete a.lineY1;
  
                  a.curve = function (_) {
                      return arguments.length ? c(curveRadial(_)) : c()._curve;
                  };
  
                  return a;
              }
  
              function pointRadial(x, y) {
                  return [(y = +y) * Math.cos(x -= Math.PI / 2), y * Math.sin(x)];
              }
  
              var slice$6 = Array.prototype.slice;
  
              function linkSource(d) {
                  return d.source;
              }
  
              function linkTarget(d) {
                  return d.target;
              }
  
              function link$2(curve) {
                  var source = linkSource,
                          target = linkTarget,
                          x = x$3,
                          y = y$3,
                          context = null;
  
                  function link() {
                      var buffer, argv = slice$6.call(arguments), s = source.apply(this, argv), t = target.apply(this, argv);
                      if (!context)
                          context = buffer = path();
                      curve(context, +x.apply(this, (argv[0] = s, argv)), +y.apply(this, argv), +x.apply(this, (argv[0] = t, argv)), +y.apply(this, argv));
                      if (buffer)
                          return context = null, buffer + "" || null;
                  }
  
                  link.source = function (_) {
                      return arguments.length ? (source = _, link) : source;
                  };
  
                  link.target = function (_) {
                      return arguments.length ? (target = _, link) : target;
                  };
  
                  link.x = function (_) {
                      return arguments.length ? (x = typeof _ === "function" ? _ : constant$b(+_), link) : x;
                  };
  
                  link.y = function (_) {
                      return arguments.length ? (y = typeof _ === "function" ? _ : constant$b(+_), link) : y;
                  };
  
                  link.context = function (_) {
                      return arguments.length ? ((context = _ == null ? null : _), link) : context;
                  };
  
                  return link;
              }
  
              function curveHorizontal(context, x0, y0, x1, y1) {
                  context.moveTo(x0, y0);
                  context.bezierCurveTo(x0 = (x0 + x1) / 2, y0, x0, y1, x1, y1);
              }
  
              function curveVertical(context, x0, y0, x1, y1) {
                  context.moveTo(x0, y0);
                  context.bezierCurveTo(x0, y0 = (y0 + y1) / 2, x1, y0, x1, y1);
              }
  
              function curveRadial$1(context, x0, y0, x1, y1) {
                  var p0 = pointRadial(x0, y0),
                          p1 = pointRadial(x0, y0 = (y0 + y1) / 2),
                          p2 = pointRadial(x1, y0),
                          p3 = pointRadial(x1, y1);
                  context.moveTo(p0[0], p0[1]);
                  context.bezierCurveTo(p1[0], p1[1], p2[0], p2[1], p3[0], p3[1]);
              }
  
              function linkHorizontal() {
                  return link$2(curveHorizontal);
              }
  
              function linkVertical() {
                  return link$2(curveVertical);
              }
  
              function linkRadial() {
                  var l = link$2(curveRadial$1);
                  l.angle = l.x, delete l.x;
                  l.radius = l.y, delete l.y;
                  return l;
              }
  
              var circle$2 = {
                  draw: function (context, size) {
                      var r = Math.sqrt(size / pi$4);
                      context.moveTo(r, 0);
                      context.arc(0, 0, r, 0, tau$4);
                  }
              };
  
              var cross$2 = {
                  draw: function (context, size) {
                      var r = Math.sqrt(size / 5) / 2;
                      context.moveTo(-3 * r, -r);
                      context.lineTo(-r, -r);
                      context.lineTo(-r, -3 * r);
                      context.lineTo(r, -3 * r);
                      context.lineTo(r, -r);
                      context.lineTo(3 * r, -r);
                      context.lineTo(3 * r, r);
                      context.lineTo(r, r);
                      context.lineTo(r, 3 * r);
                      context.lineTo(-r, 3 * r);
                      context.lineTo(-r, r);
                      context.lineTo(-3 * r, r);
                      context.closePath();
                  }
              };
  
              var tan30 = Math.sqrt(1 / 3),
                      tan30_2 = tan30 * 2;
  
              var diamond = {
                  draw: function (context, size) {
                      var y = Math.sqrt(size / tan30_2),
                              x = y * tan30;
                      context.moveTo(0, -y);
                      context.lineTo(x, 0);
                      context.lineTo(0, y);
                      context.lineTo(-x, 0);
                      context.closePath();
                  }
              };
  
              var ka = 0.89081309152928522810,
                      kr = Math.sin(pi$4 / 10) / Math.sin(7 * pi$4 / 10),
                      kx = Math.sin(tau$4 / 10) * kr,
                      ky = -Math.cos(tau$4 / 10) * kr;
  
              var star = {
                  draw: function (context, size) {
                      var r = Math.sqrt(size * ka),
                              x = kx * r,
                              y = ky * r;
                      context.moveTo(0, -r);
                      context.lineTo(x, y);
                      for (var i = 1; i < 5; ++i) {
                          var a = tau$4 * i / 5,
                                  c = Math.cos(a),
                                  s = Math.sin(a);
                          context.lineTo(s * r, -c * r);
                          context.lineTo(c * x - s * y, s * x + c * y);
                      }
                      context.closePath();
                  }
              };
  
              var square = {
                  draw: function (context, size) {
                      var w = Math.sqrt(size),
                              x = -w / 2;
                      context.rect(x, x, w, w);
                  }
              };
  
              var sqrt3 = Math.sqrt(3);
  
              var triangle = {
                  draw: function (context, size) {
                      var y = -Math.sqrt(size / (sqrt3 * 3));
                      context.moveTo(0, y * 2);
                      context.lineTo(-sqrt3 * y, -y);
                      context.lineTo(sqrt3 * y, -y);
                      context.closePath();
                  }
              };
  
              var c$2 = -0.5,
                      s = Math.sqrt(3) / 2,
                      k = 1 / Math.sqrt(12),
                      a = (k / 2 + 1) * 3;
  
              var wye = {
                  draw: function (context, size) {
                      var r = Math.sqrt(size / a),
                              x0 = r / 2,
                              y0 = r * k,
                              x1 = x0,
                              y1 = r * k + r,
                              x2 = -x1,
                              y2 = y1;
                      context.moveTo(x0, y0);
                      context.lineTo(x1, y1);
                      context.lineTo(x2, y2);
                      context.lineTo(c$2 * x0 - s * y0, s * x0 + c$2 * y0);
                      context.lineTo(c$2 * x1 - s * y1, s * x1 + c$2 * y1);
                      context.lineTo(c$2 * x2 - s * y2, s * x2 + c$2 * y2);
                      context.lineTo(c$2 * x0 + s * y0, c$2 * y0 - s * x0);
                      context.lineTo(c$2 * x1 + s * y1, c$2 * y1 - s * x1);
                      context.lineTo(c$2 * x2 + s * y2, c$2 * y2 - s * x2);
                      context.closePath();
                  }
              };
  
              var symbols = [
                  circle$2,
                  cross$2,
                  diamond,
                  square,
                  star,
                  triangle,
                  wye
              ];
  
              function symbol() {
                  var type = constant$b(circle$2),
                          size = constant$b(64),
                          context = null;
  
                  function symbol() {
                      var buffer;
                      if (!context)
                          context = buffer = path();
                      type.apply(this, arguments).draw(context, +size.apply(this, arguments));
                      if (buffer)
                          return context = null, buffer + "" || null;
                  }
  
                  symbol.type = function (_) {
                      return arguments.length ? (type = typeof _ === "function" ? _ : constant$b(_), symbol) : type;
                  };
  
                  symbol.size = function (_) {
                      return arguments.length ? (size = typeof _ === "function" ? _ : constant$b(+_), symbol) : size;
                  };
  
                  symbol.context = function (_) {
                      return arguments.length ? (context = _ == null ? null : _, symbol) : context;
                  };
  
                  return symbol;
              }
  
              function noop$3() {}
  
              function point$2(that, x, y) {
                  that._context.bezierCurveTo(
                          (2 * that._x0 + that._x1) / 3,
                          (2 * that._y0 + that._y1) / 3,
                          (that._x0 + 2 * that._x1) / 3,
                          (that._y0 + 2 * that._y1) / 3,
                          (that._x0 + 4 * that._x1 + x) / 6,
                          (that._y0 + 4 * that._y1 + y) / 6
                          );
              }
  
              function Basis(context) {
                  this._context = context;
              }
  
              Basis.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 =
                              this._y0 = this._y1 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 3:
                              point$2(this, this._x1, this._y1); // proceed
                          case 2:
                              this._context.lineTo(this._x1, this._y1);
                              break;
                      }
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3;
                              this._context.lineTo((5 * this._x0 + this._x1) / 6, (5 * this._y0 + this._y1) / 6); // proceed
                          default:
                              point$2(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = x;
                      this._y0 = this._y1, this._y1 = y;
                  }
              };
  
              function basis$2(context) {
                  return new Basis(context);
              }
  
              function BasisClosed(context) {
                  this._context = context;
              }
  
              BasisClosed.prototype = {
                  areaStart: noop$3,
                  areaEnd: noop$3,
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 =
                              this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 1:
                          {
                              this._context.moveTo(this._x2, this._y2);
                              this._context.closePath();
                              break;
                          }
                          case 2:
                          {
                              this._context.moveTo((this._x2 + 2 * this._x3) / 3, (this._y2 + 2 * this._y3) / 3);
                              this._context.lineTo((this._x3 + 2 * this._x2) / 3, (this._y3 + 2 * this._y2) / 3);
                              this._context.closePath();
                              break;
                          }
                          case 3:
                          {
                              this.point(this._x2, this._y2);
                              this.point(this._x3, this._y3);
                              this.point(this._x4, this._y4);
                              break;
                          }
                      }
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._x2 = x, this._y2 = y;
                              break;
                          case 1:
                              this._point = 2;
                              this._x3 = x, this._y3 = y;
                              break;
                          case 2:
                              this._point = 3;
                              this._x4 = x, this._y4 = y;
                              this._context.moveTo((this._x0 + 4 * this._x1 + x) / 6, (this._y0 + 4 * this._y1 + y) / 6);
                              break;
                          default:
                              point$2(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = x;
                      this._y0 = this._y1, this._y1 = y;
                  }
              };
  
              function basisClosed$1(context) {
                  return new BasisClosed(context);
              }
  
              function BasisOpen(context) {
                  this._context = context;
              }
  
              BasisOpen.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 =
                              this._y0 = this._y1 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line || (this._line !== 0 && this._point === 3))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3;
                              var x0 = (this._x0 + 4 * this._x1 + x) / 6, y0 = (this._y0 + 4 * this._y1 + y) / 6;
                              this._line ? this._context.lineTo(x0, y0) : this._context.moveTo(x0, y0);
                              break;
                          case 3:
                              this._point = 4; // proceed
                          default:
                              point$2(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = x;
                      this._y0 = this._y1, this._y1 = y;
                  }
              };
  
              function basisOpen(context) {
                  return new BasisOpen(context);
              }
  
              function Bundle(context, beta) {
                  this._basis = new Basis(context);
                  this._beta = beta;
              }
  
              Bundle.prototype = {
                  lineStart: function () {
                      this._x = [];
                      this._y = [];
                      this._basis.lineStart();
                  },
                  lineEnd: function () {
                      var x = this._x,
                              y = this._y,
                              j = x.length - 1;
  
                      if (j > 0) {
                          var x0 = x[0],
                                  y0 = y[0],
                                  dx = x[j] - x0,
                                  dy = y[j] - y0,
                                  i = -1,
                                  t;
  
                          while (++i <= j) {
                              t = i / j;
                              this._basis.point(
                                      this._beta * x[i] + (1 - this._beta) * (x0 + t * dx),
                                      this._beta * y[i] + (1 - this._beta) * (y0 + t * dy)
                                      );
                          }
                      }
  
                      this._x = this._y = null;
                      this._basis.lineEnd();
                  },
                  point: function (x, y) {
                      this._x.push(+x);
                      this._y.push(+y);
                  }
              };
  
              var bundle = (function custom(beta) {
  
                  function bundle(context) {
                      return beta === 1 ? new Basis(context) : new Bundle(context, beta);
                  }
  
                  bundle.beta = function (beta) {
                      return custom(+beta);
                  };
  
                  return bundle;
              })(0.85);
  
              function point$3(that, x, y) {
                  that._context.bezierCurveTo(
                          that._x1 + that._k * (that._x2 - that._x0),
                          that._y1 + that._k * (that._y2 - that._y0),
                          that._x2 + that._k * (that._x1 - x),
                          that._y2 + that._k * (that._y1 - y),
                          that._x2,
                          that._y2
                          );
              }
  
              function Cardinal(context, tension) {
                  this._context = context;
                  this._k = (1 - tension) / 6;
              }
  
              Cardinal.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 =
                              this._y0 = this._y1 = this._y2 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 2:
                              this._context.lineTo(this._x2, this._y2);
                              break;
                          case 3:
                              point$3(this, this._x1, this._y1);
                              break;
                      }
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2;
                              this._x1 = x, this._y1 = y;
                              break;
                          case 2:
                              this._point = 3; // proceed
                          default:
                              point$3(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var cardinal = (function custom(tension) {
  
                  function cardinal(context) {
                      return new Cardinal(context, tension);
                  }
  
                  cardinal.tension = function (tension) {
                      return custom(+tension);
                  };
  
                  return cardinal;
              })(0);
  
              function CardinalClosed(context, tension) {
                  this._context = context;
                  this._k = (1 - tension) / 6;
              }
  
              CardinalClosed.prototype = {
                  areaStart: noop$3,
                  areaEnd: noop$3,
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 = this._x5 =
                              this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = this._y5 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 1:
                          {
                              this._context.moveTo(this._x3, this._y3);
                              this._context.closePath();
                              break;
                          }
                          case 2:
                          {
                              this._context.lineTo(this._x3, this._y3);
                              this._context.closePath();
                              break;
                          }
                          case 3:
                          {
                              this.point(this._x3, this._y3);
                              this.point(this._x4, this._y4);
                              this.point(this._x5, this._y5);
                              break;
                          }
                      }
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._x3 = x, this._y3 = y;
                              break;
                          case 1:
                              this._point = 2;
                              this._context.moveTo(this._x4 = x, this._y4 = y);
                              break;
                          case 2:
                              this._point = 3;
                              this._x5 = x, this._y5 = y;
                              break;
                          default:
                              point$3(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var cardinalClosed = (function custom(tension) {
  
                  function cardinal(context) {
                      return new CardinalClosed(context, tension);
                  }
  
                  cardinal.tension = function (tension) {
                      return custom(+tension);
                  };
  
                  return cardinal;
              })(0);
  
              function CardinalOpen(context, tension) {
                  this._context = context;
                  this._k = (1 - tension) / 6;
              }
  
              CardinalOpen.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 =
                              this._y0 = this._y1 = this._y2 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line || (this._line !== 0 && this._point === 3))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3;
                              this._line ? this._context.lineTo(this._x2, this._y2) : this._context.moveTo(this._x2, this._y2);
                              break;
                          case 3:
                              this._point = 4; // proceed
                          default:
                              point$3(this, x, y);
                              break;
                      }
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var cardinalOpen = (function custom(tension) {
  
                  function cardinal(context) {
                      return new CardinalOpen(context, tension);
                  }
  
                  cardinal.tension = function (tension) {
                      return custom(+tension);
                  };
  
                  return cardinal;
              })(0);
  
              function point$4(that, x, y) {
                  var x1 = that._x1,
                          y1 = that._y1,
                          x2 = that._x2,
                          y2 = that._y2;
  
                  if (that._l01_a > epsilon$3) {
                      var a = 2 * that._l01_2a + 3 * that._l01_a * that._l12_a + that._l12_2a,
                              n = 3 * that._l01_a * (that._l01_a + that._l12_a);
                      x1 = (x1 * a - that._x0 * that._l12_2a + that._x2 * that._l01_2a) / n;
                      y1 = (y1 * a - that._y0 * that._l12_2a + that._y2 * that._l01_2a) / n;
                  }
  
                  if (that._l23_a > epsilon$3) {
                      var b = 2 * that._l23_2a + 3 * that._l23_a * that._l12_a + that._l12_2a,
                              m = 3 * that._l23_a * (that._l23_a + that._l12_a);
                      x2 = (x2 * b + that._x1 * that._l23_2a - x * that._l12_2a) / m;
                      y2 = (y2 * b + that._y1 * that._l23_2a - y * that._l12_2a) / m;
                  }
  
                  that._context.bezierCurveTo(x1, y1, x2, y2, that._x2, that._y2);
              }
  
              function CatmullRom(context, alpha) {
                  this._context = context;
                  this._alpha = alpha;
              }
  
              CatmullRom.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 =
                              this._y0 = this._y1 = this._y2 = NaN;
                      this._l01_a = this._l12_a = this._l23_a =
                              this._l01_2a = this._l12_2a = this._l23_2a =
                              this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 2:
                              this._context.lineTo(this._x2, this._y2);
                              break;
                          case 3:
                              this.point(this._x2, this._y2);
                              break;
                      }
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
  
                      if (this._point) {
                          var x23 = this._x2 - x,
                                  y23 = this._y2 - y;
                          this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
                      }
  
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3; // proceed
                          default:
                              point$4(this, x, y);
                              break;
                      }
  
                      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
                      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var catmullRom = (function custom(alpha) {
  
                  function catmullRom(context) {
                      return alpha ? new CatmullRom(context, alpha) : new Cardinal(context, 0);
                  }
  
                  catmullRom.alpha = function (alpha) {
                      return custom(+alpha);
                  };
  
                  return catmullRom;
              })(0.5);
  
              function CatmullRomClosed(context, alpha) {
                  this._context = context;
                  this._alpha = alpha;
              }
  
              CatmullRomClosed.prototype = {
                  areaStart: noop$3,
                  areaEnd: noop$3,
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 = this._x5 =
                              this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = this._y5 = NaN;
                      this._l01_a = this._l12_a = this._l23_a =
                              this._l01_2a = this._l12_2a = this._l23_2a =
                              this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 1:
                          {
                              this._context.moveTo(this._x3, this._y3);
                              this._context.closePath();
                              break;
                          }
                          case 2:
                          {
                              this._context.lineTo(this._x3, this._y3);
                              this._context.closePath();
                              break;
                          }
                          case 3:
                          {
                              this.point(this._x3, this._y3);
                              this.point(this._x4, this._y4);
                              this.point(this._x5, this._y5);
                              break;
                          }
                      }
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
  
                      if (this._point) {
                          var x23 = this._x2 - x,
                                  y23 = this._y2 - y;
                          this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
                      }
  
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._x3 = x, this._y3 = y;
                              break;
                          case 1:
                              this._point = 2;
                              this._context.moveTo(this._x4 = x, this._y4 = y);
                              break;
                          case 2:
                              this._point = 3;
                              this._x5 = x, this._y5 = y;
                              break;
                          default:
                              point$4(this, x, y);
                              break;
                      }
  
                      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
                      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var catmullRomClosed = (function custom(alpha) {
  
                  function catmullRom(context) {
                      return alpha ? new CatmullRomClosed(context, alpha) : new CardinalClosed(context, 0);
                  }
  
                  catmullRom.alpha = function (alpha) {
                      return custom(+alpha);
                  };
  
                  return catmullRom;
              })(0.5);
  
              function CatmullRomOpen(context, alpha) {
                  this._context = context;
                  this._alpha = alpha;
              }
  
              CatmullRomOpen.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 = this._x2 =
                              this._y0 = this._y1 = this._y2 = NaN;
                      this._l01_a = this._l12_a = this._l23_a =
                              this._l01_2a = this._l12_2a = this._l23_2a =
                              this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._line || (this._line !== 0 && this._point === 3))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
  
                      if (this._point) {
                          var x23 = this._x2 - x,
                                  y23 = this._y2 - y;
                          this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
                      }
  
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3;
                              this._line ? this._context.lineTo(this._x2, this._y2) : this._context.moveTo(this._x2, this._y2);
                              break;
                          case 3:
                              this._point = 4; // proceed
                          default:
                              point$4(this, x, y);
                              break;
                      }
  
                      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
                      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
                      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
                      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
                  }
              };
  
              var catmullRomOpen = (function custom(alpha) {
  
                  function catmullRom(context) {
                      return alpha ? new CatmullRomOpen(context, alpha) : new CardinalOpen(context, 0);
                  }
  
                  catmullRom.alpha = function (alpha) {
                      return custom(+alpha);
                  };
  
                  return catmullRom;
              })(0.5);
  
              function LinearClosed(context) {
                  this._context = context;
              }
  
              LinearClosed.prototype = {
                  areaStart: noop$3,
                  areaEnd: noop$3,
                  lineStart: function () {
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (this._point)
                          this._context.closePath();
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      if (this._point)
                          this._context.lineTo(x, y);
                      else
                          this._point = 1, this._context.moveTo(x, y);
                  }
              };
  
              function linearClosed(context) {
                  return new LinearClosed(context);
              }
  
              function sign$1(x) {
                  return x < 0 ? -1 : 1;
              }
  
  // Calculate the slopes of the tangents (Hermite-type interpolation) based on
  // the following paper: Steffen, M. 1990. A Simple Method for Monotonic
  // Interpolation in One Dimension. Astronomy and Astrophysics, Vol. 239, NO.
  // NOV(II), P. 443, 1990.
              function slope3(that, x2, y2) {
                  var h0 = that._x1 - that._x0,
                          h1 = x2 - that._x1,
                          s0 = (that._y1 - that._y0) / (h0 || h1 < 0 && -0),
                          s1 = (y2 - that._y1) / (h1 || h0 < 0 && -0),
                          p = (s0 * h1 + s1 * h0) / (h0 + h1);
                  return (sign$1(s0) + sign$1(s1)) * Math.min(Math.abs(s0), Math.abs(s1), 0.5 * Math.abs(p)) || 0;
              }
  
  // Calculate a one-sided slope.
              function slope2(that, t) {
                  var h = that._x1 - that._x0;
                  return h ? (3 * (that._y1 - that._y0) / h - t) / 2 : t;
              }
  
  // According to https://en.wikipedia.org/wiki/Cubic_Hermite_spline#Representations
  // "you can express cubic Hermite interpolation in terms of cubic Bézier curves
  // with respect to the four values p0, p0 + m0 / 3, p1 - m1 / 3, p1".
              function point$5(that, t0, t1) {
                  var x0 = that._x0,
                          y0 = that._y0,
                          x1 = that._x1,
                          y1 = that._y1,
                          dx = (x1 - x0) / 3;
                  that._context.bezierCurveTo(x0 + dx, y0 + dx * t0, x1 - dx, y1 - dx * t1, x1, y1);
              }
  
              function MonotoneX(context) {
                  this._context = context;
              }
  
              MonotoneX.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x0 = this._x1 =
                              this._y0 = this._y1 =
                              this._t0 = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      switch (this._point) {
                          case 2:
                              this._context.lineTo(this._x1, this._y1);
                              break;
                          case 3:
                              point$5(this, this._t0, slope2(this, this._t0));
                              break;
                      }
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      var t1 = NaN;
  
                      x = +x, y = +y;
                      if (x === this._x1 && y === this._y1)
                          return; // Ignore coincident points.
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2;
                              break;
                          case 2:
                              this._point = 3;
                              point$5(this, slope2(this, t1 = slope3(this, x, y)), t1);
                              break;
                          default:
                              point$5(this, this._t0, t1 = slope3(this, x, y));
                              break;
                      }
  
                      this._x0 = this._x1, this._x1 = x;
                      this._y0 = this._y1, this._y1 = y;
                      this._t0 = t1;
                  }
              };
  
              function MonotoneY(context) {
                  this._context = new ReflectContext(context);
              }
  
              (MonotoneY.prototype = Object.create(MonotoneX.prototype)).point = function (x, y) {
                  MonotoneX.prototype.point.call(this, y, x);
              };
  
              function ReflectContext(context) {
                  this._context = context;
              }
  
              ReflectContext.prototype = {
                  moveTo: function (x, y) {
                      this._context.moveTo(y, x);
                  },
                  closePath: function () {
                      this._context.closePath();
                  },
                  lineTo: function (x, y) {
                      this._context.lineTo(y, x);
                  },
                  bezierCurveTo: function (x1, y1, x2, y2, x, y) {
                      this._context.bezierCurveTo(y1, x1, y2, x2, y, x);
                  }
              };
  
              function monotoneX(context) {
                  return new MonotoneX(context);
              }
  
              function monotoneY(context) {
                  return new MonotoneY(context);
              }
  
              function Natural(context) {
                  this._context = context;
              }
  
              Natural.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x = [];
                      this._y = [];
                  },
                  lineEnd: function () {
                      var x = this._x,
                              y = this._y,
                              n = x.length;
  
                      if (n) {
                          this._line ? this._context.lineTo(x[0], y[0]) : this._context.moveTo(x[0], y[0]);
                          if (n === 2) {
                              this._context.lineTo(x[1], y[1]);
                          } else {
                              var px = controlPoints(x),
                                      py = controlPoints(y);
                              for (var i0 = 0, i1 = 1; i1 < n; ++i0, ++i1) {
                                  this._context.bezierCurveTo(px[0][i0], py[0][i0], px[1][i0], py[1][i0], x[i1], y[i1]);
                              }
                          }
                      }
  
                      if (this._line || (this._line !== 0 && n === 1))
                          this._context.closePath();
                      this._line = 1 - this._line;
                      this._x = this._y = null;
                  },
                  point: function (x, y) {
                      this._x.push(+x);
                      this._y.push(+y);
                  }
              };
  
  // See https://www.particleincell.com/2012/bezier-splines/ for derivation.
              function controlPoints(x) {
                  var i,
                          n = x.length - 1,
                          m,
                          a = new Array(n),
                          b = new Array(n),
                          r = new Array(n);
                  a[0] = 0, b[0] = 2, r[0] = x[0] + 2 * x[1];
                  for (i = 1; i < n - 1; ++i)
                      a[i] = 1, b[i] = 4, r[i] = 4 * x[i] + 2 * x[i + 1];
                  a[n - 1] = 2, b[n - 1] = 7, r[n - 1] = 8 * x[n - 1] + x[n];
                  for (i = 1; i < n; ++i)
                      m = a[i] / b[i - 1], b[i] -= m, r[i] -= m * r[i - 1];
                  a[n - 1] = r[n - 1] / b[n - 1];
                  for (i = n - 2; i >= 0; --i)
                      a[i] = (r[i] - a[i + 1]) / b[i];
                  b[n - 1] = (x[n] + a[n - 1]) / 2;
                  for (i = 0; i < n - 1; ++i)
                      b[i] = 2 * x[i + 1] - a[i + 1];
                  return [a, b];
              }
  
              function natural(context) {
                  return new Natural(context);
              }
  
              function Step(context, t) {
                  this._context = context;
                  this._t = t;
              }
  
              Step.prototype = {
                  areaStart: function () {
                      this._line = 0;
                  },
                  areaEnd: function () {
                      this._line = NaN;
                  },
                  lineStart: function () {
                      this._x = this._y = NaN;
                      this._point = 0;
                  },
                  lineEnd: function () {
                      if (0 < this._t && this._t < 1 && this._point === 2)
                          this._context.lineTo(this._x, this._y);
                      if (this._line || (this._line !== 0 && this._point === 1))
                          this._context.closePath();
                      if (this._line >= 0)
                          this._t = 1 - this._t, this._line = 1 - this._line;
                  },
                  point: function (x, y) {
                      x = +x, y = +y;
                      switch (this._point) {
                          case 0:
                              this._point = 1;
                              this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
                              break;
                          case 1:
                              this._point = 2; // proceed
                          default:
                          {
                              if (this._t <= 0) {
                                  this._context.lineTo(this._x, y);
                                  this._context.lineTo(x, y);
                              } else {
                                  var x1 = this._x * (1 - this._t) + x * this._t;
                                  this._context.lineTo(x1, this._y);
                                  this._context.lineTo(x1, y);
                              }
                              break;
                          }
                      }
                      this._x = x, this._y = y;
                  }
              };
  
              function step(context) {
                  return new Step(context, 0.5);
              }
  
              function stepBefore(context) {
                  return new Step(context, 0);
              }
  
              function stepAfter(context) {
                  return new Step(context, 1);
              }
  
              function none$1(series, order) {
                  if (!((n = series.length) > 1))
                      return;
                  for (var i = 1, j, s0, s1 = series[order[0]], n, m = s1.length; i < n; ++i) {
                      s0 = s1, s1 = series[order[i]];
                      for (j = 0; j < m; ++j) {
                          s1[j][1] += s1[j][0] = isNaN(s0[j][1]) ? s0[j][0] : s0[j][1];
                      }
                  }
              }
  
              function none$2(series) {
                  var n = series.length, o = new Array(n);
                  while (--n >= 0)
                      o[n] = n;
                  return o;
              }
  
              function stackValue(d, key) {
                  return d[key];
              }
  
              function stack() {
                  var keys = constant$b([]),
                          order = none$2,
                          offset = none$1,
                          value = stackValue;
  
                  function stack(data) {
                      var kz = keys.apply(this, arguments),
                              i,
                              m = data.length,
                              n = kz.length,
                              sz = new Array(n),
                              oz;
  
                      for (i = 0; i < n; ++i) {
                          for (var ki = kz[i], si = sz[i] = new Array(m), j = 0, sij; j < m; ++j) {
                              si[j] = sij = [0, +value(data[j], ki, j, data)];
                              sij.data = data[j];
                          }
                          si.key = ki;
                      }
  
                      for (i = 0, oz = order(sz); i < n; ++i) {
                          sz[oz[i]].index = i;
                      }
  
                      offset(sz, oz);
                      return sz;
                  }
  
                  stack.keys = function (_) {
                      return arguments.length ? (keys = typeof _ === "function" ? _ : constant$b(slice$6.call(_)), stack) : keys;
                  };
  
                  stack.value = function (_) {
                      return arguments.length ? (value = typeof _ === "function" ? _ : constant$b(+_), stack) : value;
                  };
  
                  stack.order = function (_) {
                      return arguments.length ? (order = _ == null ? none$2 : typeof _ === "function" ? _ : constant$b(slice$6.call(_)), stack) : order;
                  };
  
                  stack.offset = function (_) {
                      return arguments.length ? (offset = _ == null ? none$1 : _, stack) : offset;
                  };
  
                  return stack;
              }
  
              function expand(series, order) {
                  if (!((n = series.length) > 0))
                      return;
                  for (var i, n, j = 0, m = series[0].length, y; j < m; ++j) {
                      for (y = i = 0; i < n; ++i)
                          y += series[i][j][1] || 0;
                      if (y)
                          for (i = 0; i < n; ++i)
                              series[i][j][1] /= y;
                  }
                  none$1(series, order);
              }
  
              function diverging$1(series, order) {
                  if (!((n = series.length) > 0))
                      return;
                  for (var i, j = 0, d, dy, yp, yn, n, m = series[order[0]].length; j < m; ++j) {
                      for (yp = yn = 0, i = 0; i < n; ++i) {
                          if ((dy = (d = series[order[i]][j])[1] - d[0]) > 0) {
                              d[0] = yp, d[1] = yp += dy;
                          } else if (dy < 0) {
                              d[1] = yn, d[0] = yn += dy;
                          } else {
                              d[0] = 0, d[1] = dy;
                          }
                      }
                  }
              }
  
              function silhouette(series, order) {
                  if (!((n = series.length) > 0))
                      return;
                  for (var j = 0, s0 = series[order[0]], n, m = s0.length; j < m; ++j) {
                      for (var i = 0, y = 0; i < n; ++i)
                          y += series[i][j][1] || 0;
                      s0[j][1] += s0[j][0] = -y / 2;
                  }
                  none$1(series, order);
              }
  
              function wiggle(series, order) {
                  if (!((n = series.length) > 0) || !((m = (s0 = series[order[0]]).length) > 0))
                      return;
                  for (var y = 0, j = 1, s0, m, n; j < m; ++j) {
                      for (var i = 0, s1 = 0, s2 = 0; i < n; ++i) {
                          var si = series[order[i]],
                                  sij0 = si[j][1] || 0,
                                  sij1 = si[j - 1][1] || 0,
                                  s3 = (sij0 - sij1) / 2;
                          for (var k = 0; k < i; ++k) {
                              var sk = series[order[k]],
                                      skj0 = sk[j][1] || 0,
                                      skj1 = sk[j - 1][1] || 0;
                              s3 += skj0 - skj1;
                          }
                          s1 += sij0, s2 += s3 * sij0;
                      }
                      s0[j - 1][1] += s0[j - 1][0] = y;
                      if (s1)
                          y -= s2 / s1;
                  }
                  s0[j - 1][1] += s0[j - 1][0] = y;
                  none$1(series, order);
              }
  
              function appearance(series) {
                  var peaks = series.map(peak);
                  return none$2(series).sort(function (a, b) {
                      return peaks[a] - peaks[b];
                  });
              }
  
              function peak(series) {
                  var i = -1, j = 0, n = series.length, vi, vj = -Infinity;
                  while (++i < n)
                      if ((vi = +series[i][1]) > vj)
                          vj = vi, j = i;
                  return j;
              }
  
              function ascending$3(series) {
                  var sums = series.map(sum$2);
                  return none$2(series).sort(function (a, b) {
                      return sums[a] - sums[b];
                  });
              }
  
              function sum$2(series) {
                  var s = 0, i = -1, n = series.length, v;
                  while (++i < n)
                      if (v = +series[i][1])
                          s += v;
                  return s;
              }
  
              function descending$2(series) {
                  return ascending$3(series).reverse();
              }
  
              function insideOut(series) {
                  var n = series.length,
                          i,
                          j,
                          sums = series.map(sum$2),
                          order = appearance(series),
                          top = 0,
                          bottom = 0,
                          tops = [],
                          bottoms = [];
  
                  for (i = 0; i < n; ++i) {
                      j = order[i];
                      if (top < bottom) {
                          top += sums[j];
                          tops.push(j);
                      } else {
                          bottom += sums[j];
                          bottoms.push(j);
                      }
                  }
  
                  return bottoms.reverse().concat(tops);
              }
  
              function reverse(series) {
                  return none$2(series).reverse();
              }
  
              function constant$c(x) {
                  return function () {
                      return x;
                  };
              }
  
              function x$4(d) {
                  return d[0];
              }
  
              function y$4(d) {
                  return d[1];
              }
  
              function RedBlackTree() {
                  this._ = null; // root node
              }
  
              function RedBlackNode(node) {
                  node.U = // parent node
                          node.C = // color - true for red, false for black
                          node.L = // left node
                          node.R = // right node
                          node.P = // previous node
                          node.N = null; // next node
              }
  
              RedBlackTree.prototype = {
                  constructor: RedBlackTree,
  
                  insert: function (after, node) {
                      var parent, grandpa, uncle;
  
                      if (after) {
                          node.P = after;
                          node.N = after.N;
                          if (after.N)
                              after.N.P = node;
                          after.N = node;
                          if (after.R) {
                              after = after.R;
                              while (after.L)
                                  after = after.L;
                              after.L = node;
                          } else {
                              after.R = node;
                          }
                          parent = after;
                      } else if (this._) {
                          after = RedBlackFirst(this._);
                          node.P = null;
                          node.N = after;
                          after.P = after.L = node;
                          parent = after;
                      } else {
                          node.P = node.N = null;
                          this._ = node;
                          parent = null;
                      }
                      node.L = node.R = null;
                      node.U = parent;
                      node.C = true;
  
                      after = node;
                      while (parent && parent.C) {
                          grandpa = parent.U;
                          if (parent === grandpa.L) {
                              uncle = grandpa.R;
                              if (uncle && uncle.C) {
                                  parent.C = uncle.C = false;
                                  grandpa.C = true;
                                  after = grandpa;
                              } else {
                                  if (after === parent.R) {
                                      RedBlackRotateLeft(this, parent);
                                      after = parent;
                                      parent = after.U;
                                  }
                                  parent.C = false;
                                  grandpa.C = true;
                                  RedBlackRotateRight(this, grandpa);
                              }
                          } else {
                              uncle = grandpa.L;
                              if (uncle && uncle.C) {
                                  parent.C = uncle.C = false;
                                  grandpa.C = true;
                                  after = grandpa;
                              } else {
                                  if (after === parent.L) {
                                      RedBlackRotateRight(this, parent);
                                      after = parent;
                                      parent = after.U;
                                  }
                                  parent.C = false;
                                  grandpa.C = true;
                                  RedBlackRotateLeft(this, grandpa);
                              }
                          }
                          parent = after.U;
                      }
                      this._.C = false;
                  },
  
                  remove: function (node) {
                      if (node.N)
                          node.N.P = node.P;
                      if (node.P)
                          node.P.N = node.N;
                      node.N = node.P = null;
  
                      var parent = node.U,
                              sibling,
                              left = node.L,
                              right = node.R,
                              next,
                              red;
  
                      if (!left)
                          next = right;
                      else if (!right)
                          next = left;
                      else
                          next = RedBlackFirst(right);
  
                      if (parent) {
                          if (parent.L === node)
                              parent.L = next;
                          else
                              parent.R = next;
                      } else {
                          this._ = next;
                      }
  
                      if (left && right) {
                          red = next.C;
                          next.C = node.C;
                          next.L = left;
                          left.U = next;
                          if (next !== right) {
                              parent = next.U;
                              next.U = node.U;
                              node = next.R;
                              parent.L = node;
                              next.R = right;
                              right.U = next;
                          } else {
                              next.U = parent;
                              parent = next;
                              node = next.R;
                          }
                      } else {
                          red = node.C;
                          node = next;
                      }
  
                      if (node)
                          node.U = parent;
                      if (red)
                          return;
                      if (node && node.C) {
                          node.C = false;
                          return;
                      }
  
                      do {
                          if (node === this._)
                              break;
                          if (node === parent.L) {
                              sibling = parent.R;
                              if (sibling.C) {
                                  sibling.C = false;
                                  parent.C = true;
                                  RedBlackRotateLeft(this, parent);
                                  sibling = parent.R;
                              }
                              if ((sibling.L && sibling.L.C)
                                      || (sibling.R && sibling.R.C)) {
                                  if (!sibling.R || !sibling.R.C) {
                                      sibling.L.C = false;
                                      sibling.C = true;
                                      RedBlackRotateRight(this, sibling);
                                      sibling = parent.R;
                                  }
                                  sibling.C = parent.C;
                                  parent.C = sibling.R.C = false;
                                  RedBlackRotateLeft(this, parent);
                                  node = this._;
                                  break;
                              }
                          } else {
                              sibling = parent.L;
                              if (sibling.C) {
                                  sibling.C = false;
                                  parent.C = true;
                                  RedBlackRotateRight(this, parent);
                                  sibling = parent.L;
                              }
                              if ((sibling.L && sibling.L.C)
                                      || (sibling.R && sibling.R.C)) {
                                  if (!sibling.L || !sibling.L.C) {
                                      sibling.R.C = false;
                                      sibling.C = true;
                                      RedBlackRotateLeft(this, sibling);
                                      sibling = parent.L;
                                  }
                                  sibling.C = parent.C;
                                  parent.C = sibling.L.C = false;
                                  RedBlackRotateRight(this, parent);
                                  node = this._;
                                  break;
                              }
                          }
                          sibling.C = true;
                          node = parent;
                          parent = parent.U;
                      } while (!node.C);
  
                      if (node)
                          node.C = false;
                  }
              };
  
              function RedBlackRotateLeft(tree, node) {
                  var p = node,
                          q = node.R,
                          parent = p.U;
  
                  if (parent) {
                      if (parent.L === p)
                          parent.L = q;
                      else
                          parent.R = q;
                  } else {
                      tree._ = q;
                  }
  
                  q.U = parent;
                  p.U = q;
                  p.R = q.L;
                  if (p.R)
                      p.R.U = p;
                  q.L = p;
              }
  
              function RedBlackRotateRight(tree, node) {
                  var p = node,
                          q = node.L,
                          parent = p.U;
  
                  if (parent) {
                      if (parent.L === p)
                          parent.L = q;
                      else
                          parent.R = q;
                  } else {
                      tree._ = q;
                  }
  
                  q.U = parent;
                  p.U = q;
                  p.L = q.R;
                  if (p.L)
                      p.L.U = p;
                  q.R = p;
              }
  
              function RedBlackFirst(node) {
                  while (node.L)
                      node = node.L;
                  return node;
              }
  
              function createEdge(left, right, v0, v1) {
                  var edge = [null, null],
                          index = edges.push(edge) - 1;
                  edge.left = left;
                  edge.right = right;
                  if (v0)
                      setEdgeEnd(edge, left, right, v0);
                  if (v1)
                      setEdgeEnd(edge, right, left, v1);
                  cells[left.index].halfedges.push(index);
                  cells[right.index].halfedges.push(index);
                  return edge;
              }
  
              function createBorderEdge(left, v0, v1) {
                  var edge = [v0, v1];
                  edge.left = left;
                  return edge;
              }
  
              function setEdgeEnd(edge, left, right, vertex) {
                  if (!edge[0] && !edge[1]) {
                      edge[0] = vertex;
                      edge.left = left;
                      edge.right = right;
                  } else if (edge.left === right) {
                      edge[1] = vertex;
                  } else {
                      edge[0] = vertex;
                  }
              }
  
  // Liang–Barsky line clipping.
              function clipEdge(edge, x0, y0, x1, y1) {
                  var a = edge[0],
                          b = edge[1],
                          ax = a[0],
                          ay = a[1],
                          bx = b[0],
                          by = b[1],
                          t0 = 0,
                          t1 = 1,
                          dx = bx - ax,
                          dy = by - ay,
                          r;
  
                  r = x0 - ax;
                  if (!dx && r > 0)
                      return;
                  r /= dx;
                  if (dx < 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  } else if (dx > 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  }
  
                  r = x1 - ax;
                  if (!dx && r < 0)
                      return;
                  r /= dx;
                  if (dx < 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  } else if (dx > 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  }
  
                  r = y0 - ay;
                  if (!dy && r > 0)
                      return;
                  r /= dy;
                  if (dy < 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  } else if (dy > 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  }
  
                  r = y1 - ay;
                  if (!dy && r < 0)
                      return;
                  r /= dy;
                  if (dy < 0) {
                      if (r > t1)
                          return;
                      if (r > t0)
                          t0 = r;
                  } else if (dy > 0) {
                      if (r < t0)
                          return;
                      if (r < t1)
                          t1 = r;
                  }
  
                  if (!(t0 > 0) && !(t1 < 1))
                      return true; // TODO Better check?
  
                  if (t0 > 0)
                      edge[0] = [ax + t0 * dx, ay + t0 * dy];
                  if (t1 < 1)
                      edge[1] = [ax + t1 * dx, ay + t1 * dy];
                  return true;
              }
  
              function connectEdge(edge, x0, y0, x1, y1) {
                  var v1 = edge[1];
                  if (v1)
                      return true;
  
                  var v0 = edge[0],
                          left = edge.left,
                          right = edge.right,
                          lx = left[0],
                          ly = left[1],
                          rx = right[0],
                          ry = right[1],
                          fx = (lx + rx) / 2,
                          fy = (ly + ry) / 2,
                          fm,
                          fb;
  
                  if (ry === ly) {
                      if (fx < x0 || fx >= x1)
                          return;
                      if (lx > rx) {
                          if (!v0)
                              v0 = [fx, y0];
                          else if (v0[1] >= y1)
                              return;
                          v1 = [fx, y1];
                      } else {
                          if (!v0)
                              v0 = [fx, y1];
                          else if (v0[1] < y0)
                              return;
                          v1 = [fx, y0];
                      }
                  } else {
                      fm = (lx - rx) / (ry - ly);
                      fb = fy - fm * fx;
                      if (fm < -1 || fm > 1) {
                          if (lx > rx) {
                              if (!v0)
                                  v0 = [(y0 - fb) / fm, y0];
                              else if (v0[1] >= y1)
                                  return;
                              v1 = [(y1 - fb) / fm, y1];
                          } else {
                              if (!v0)
                                  v0 = [(y1 - fb) / fm, y1];
                              else if (v0[1] < y0)
                                  return;
                              v1 = [(y0 - fb) / fm, y0];
                          }
                      } else {
                          if (ly < ry) {
                              if (!v0)
                                  v0 = [x0, fm * x0 + fb];
                              else if (v0[0] >= x1)
                                  return;
                              v1 = [x1, fm * x1 + fb];
                          } else {
                              if (!v0)
                                  v0 = [x1, fm * x1 + fb];
                              else if (v0[0] < x0)
                                  return;
                              v1 = [x0, fm * x0 + fb];
                          }
                      }
                  }
  
                  edge[0] = v0;
                  edge[1] = v1;
                  return true;
              }
  
              function clipEdges(x0, y0, x1, y1) {
                  var i = edges.length,
                          edge;
  
                  while (i--) {
                      if (!connectEdge(edge = edges[i], x0, y0, x1, y1)
                              || !clipEdge(edge, x0, y0, x1, y1)
                              || !(Math.abs(edge[0][0] - edge[1][0]) > epsilon$4
                                      || Math.abs(edge[0][1] - edge[1][1]) > epsilon$4)) {
                          delete edges[i];
                      }
                  }
              }
  
              function createCell(site) {
                  return cells[site.index] = {
                      site: site,
                      halfedges: []
                  };
              }
  
              function cellHalfedgeAngle(cell, edge) {
                  var site = cell.site,
                          va = edge.left,
                          vb = edge.right;
                  if (site === vb)
                      vb = va, va = site;
                  if (vb)
                      return Math.atan2(vb[1] - va[1], vb[0] - va[0]);
                  if (site === va)
                      va = edge[1], vb = edge[0];
                  else
                      va = edge[0], vb = edge[1];
                  return Math.atan2(va[0] - vb[0], vb[1] - va[1]);
              }
  
              function cellHalfedgeStart(cell, edge) {
                  return edge[+(edge.left !== cell.site)];
              }
  
              function cellHalfedgeEnd(cell, edge) {
                  return edge[+(edge.left === cell.site)];
              }
  
              function sortCellHalfedges() {
                  for (var i = 0, n = cells.length, cell, halfedges, j, m; i < n; ++i) {
                      if ((cell = cells[i]) && (m = (halfedges = cell.halfedges).length)) {
                          var index = new Array(m),
                                  array = new Array(m);
                          for (j = 0; j < m; ++j)
                              index[j] = j, array[j] = cellHalfedgeAngle(cell, edges[halfedges[j]]);
                          index.sort(function (i, j) {
                              return array[j] - array[i];
                          });
                          for (j = 0; j < m; ++j)
                              array[j] = halfedges[index[j]];
                          for (j = 0; j < m; ++j)
                              halfedges[j] = array[j];
                      }
                  }
              }
  
              function clipCells(x0, y0, x1, y1) {
                  var nCells = cells.length,
                          iCell,
                          cell,
                          site,
                          iHalfedge,
                          halfedges,
                          nHalfedges,
                          start,
                          startX,
                          startY,
                          end,
                          endX,
                          endY,
                          cover = true;
  
                  for (iCell = 0; iCell < nCells; ++iCell) {
                      if (cell = cells[iCell]) {
                          site = cell.site;
                          halfedges = cell.halfedges;
                          iHalfedge = halfedges.length;
  
                          // Remove any dangling clipped edges.
                          while (iHalfedge--) {
                              if (!edges[halfedges[iHalfedge]]) {
                                  halfedges.splice(iHalfedge, 1);
                              }
                          }
  
                          // Insert any border edges as necessary.
                          iHalfedge = 0, nHalfedges = halfedges.length;
                          while (iHalfedge < nHalfedges) {
                              end = cellHalfedgeEnd(cell, edges[halfedges[iHalfedge]]), endX = end[0], endY = end[1];
                              start = cellHalfedgeStart(cell, edges[halfedges[++iHalfedge % nHalfedges]]), startX = start[0], startY = start[1];
                              if (Math.abs(endX - startX) > epsilon$4 || Math.abs(endY - startY) > epsilon$4) {
                                  halfedges.splice(iHalfedge, 0, edges.push(createBorderEdge(site, end,
                                          Math.abs(endX - x0) < epsilon$4 && y1 - endY > epsilon$4 ? [x0, Math.abs(startX - x0) < epsilon$4 ? startY : y1]
                                          : Math.abs(endY - y1) < epsilon$4 && x1 - endX > epsilon$4 ? [Math.abs(startY - y1) < epsilon$4 ? startX : x1, y1]
                                          : Math.abs(endX - x1) < epsilon$4 && endY - y0 > epsilon$4 ? [x1, Math.abs(startX - x1) < epsilon$4 ? startY : y0]
                                          : Math.abs(endY - y0) < epsilon$4 && endX - x0 > epsilon$4 ? [Math.abs(startY - y0) < epsilon$4 ? startX : x0, y0]
                                          : null)) - 1);
                                  ++nHalfedges;
                              }
                          }
  
                          if (nHalfedges)
                              cover = false;
                      }
                  }
  
                  // If there weren’t any edges, have the closest site cover the extent.
                  // It doesn’t matter which corner of the extent we measure!
                  if (cover) {
                      var dx, dy, d2, dc = Infinity;
  
                      for (iCell = 0, cover = null; iCell < nCells; ++iCell) {
                          if (cell = cells[iCell]) {
                              site = cell.site;
                              dx = site[0] - x0;
                              dy = site[1] - y0;
                              d2 = dx * dx + dy * dy;
                              if (d2 < dc)
                                  dc = d2, cover = cell;
                          }
                      }
  
                      if (cover) {
                          var v00 = [x0, y0], v01 = [x0, y1], v11 = [x1, y1], v10 = [x1, y0];
                          cover.halfedges.push(
                                  edges.push(createBorderEdge(site = cover.site, v00, v01)) - 1,
                                  edges.push(createBorderEdge(site, v01, v11)) - 1,
                                  edges.push(createBorderEdge(site, v11, v10)) - 1,
                                  edges.push(createBorderEdge(site, v10, v00)) - 1
                                  );
                      }
                  }
  
                  // Lastly delete any cells with no edges; these were entirely clipped.
                  for (iCell = 0; iCell < nCells; ++iCell) {
                      if (cell = cells[iCell]) {
                          if (!cell.halfedges.length) {
                              delete cells[iCell];
                          }
                      }
                  }
              }
  
              var circlePool = [];
  
              var firstCircle;
  
              function Circle() {
                  RedBlackNode(this);
                  this.x =
                          this.y =
                          this.arc =
                          this.site =
                          this.cy = null;
              }
  
              function attachCircle(arc) {
                  var lArc = arc.P,
                          rArc = arc.N;
  
                  if (!lArc || !rArc)
                      return;
  
                  var lSite = lArc.site,
                          cSite = arc.site,
                          rSite = rArc.site;
  
                  if (lSite === rSite)
                      return;
  
                  var bx = cSite[0],
                          by = cSite[1],
                          ax = lSite[0] - bx,
                          ay = lSite[1] - by,
                          cx = rSite[0] - bx,
                          cy = rSite[1] - by;
  
                  var d = 2 * (ax * cy - ay * cx);
                  if (d >= -epsilon2$2)
                      return;
  
                  var ha = ax * ax + ay * ay,
                          hc = cx * cx + cy * cy,
                          x = (cy * ha - ay * hc) / d,
                          y = (ax * hc - cx * ha) / d;
  
                  var circle = circlePool.pop() || new Circle;
                  circle.arc = arc;
                  circle.site = cSite;
                  circle.x = x + bx;
                  circle.y = (circle.cy = y + by) + Math.sqrt(x * x + y * y); // y bottom
  
                  arc.circle = circle;
  
                  var before = null,
                          node = circles._;
  
                  while (node) {
                      if (circle.y < node.y || (circle.y === node.y && circle.x <= node.x)) {
                          if (node.L)
                              node = node.L;
                          else {
                              before = node.P;
                              break;
                          }
                      } else {
                          if (node.R)
                              node = node.R;
                          else {
                              before = node;
                              break;
                          }
                      }
                  }
  
                  circles.insert(before, circle);
                  if (!before)
                      firstCircle = circle;
              }
  
              function detachCircle(arc) {
                  var circle = arc.circle;
                  if (circle) {
                      if (!circle.P)
                          firstCircle = circle.N;
                      circles.remove(circle);
                      circlePool.push(circle);
                      RedBlackNode(circle);
                      arc.circle = null;
                  }
              }
  
              var beachPool = [];
  
              function Beach() {
                  RedBlackNode(this);
                  this.edge =
                          this.site =
                          this.circle = null;
              }
  
              function createBeach(site) {
                  var beach = beachPool.pop() || new Beach;
                  beach.site = site;
                  return beach;
              }
  
              function detachBeach(beach) {
                  detachCircle(beach);
                  beaches.remove(beach);
                  beachPool.push(beach);
                  RedBlackNode(beach);
              }
  
              function removeBeach(beach) {
                  var circle = beach.circle,
                          x = circle.x,
                          y = circle.cy,
                          vertex = [x, y],
                          previous = beach.P,
                          next = beach.N,
                          disappearing = [beach];
  
                  detachBeach(beach);
  
                  var lArc = previous;
                  while (lArc.circle
                          && Math.abs(x - lArc.circle.x) < epsilon$4
                          && Math.abs(y - lArc.circle.cy) < epsilon$4) {
                      previous = lArc.P;
                      disappearing.unshift(lArc);
                      detachBeach(lArc);
                      lArc = previous;
                  }
  
                  disappearing.unshift(lArc);
                  detachCircle(lArc);
  
                  var rArc = next;
                  while (rArc.circle
                          && Math.abs(x - rArc.circle.x) < epsilon$4
                          && Math.abs(y - rArc.circle.cy) < epsilon$4) {
                      next = rArc.N;
                      disappearing.push(rArc);
                      detachBeach(rArc);
                      rArc = next;
                  }
  
                  disappearing.push(rArc);
                  detachCircle(rArc);
  
                  var nArcs = disappearing.length,
                          iArc;
                  for (iArc = 1; iArc < nArcs; ++iArc) {
                      rArc = disappearing[iArc];
                      lArc = disappearing[iArc - 1];
                      setEdgeEnd(rArc.edge, lArc.site, rArc.site, vertex);
                  }
  
                  lArc = disappearing[0];
                  rArc = disappearing[nArcs - 1];
                  rArc.edge = createEdge(lArc.site, rArc.site, null, vertex);
  
                  attachCircle(lArc);
                  attachCircle(rArc);
              }
  
              function addBeach(site) {
                  var x = site[0],
                          directrix = site[1],
                          lArc,
                          rArc,
                          dxl,
                          dxr,
                          node = beaches._;
  
                  while (node) {
                      dxl = leftBreakPoint(node, directrix) - x;
                      if (dxl > epsilon$4)
                          node = node.L;
                      else {
                          dxr = x - rightBreakPoint(node, directrix);
                          if (dxr > epsilon$4) {
                              if (!node.R) {
                                  lArc = node;
                                  break;
                              }
                              node = node.R;
                          } else {
                              if (dxl > -epsilon$4) {
                                  lArc = node.P;
                                  rArc = node;
                              } else if (dxr > -epsilon$4) {
                                  lArc = node;
                                  rArc = node.N;
                              } else {
                                  lArc = rArc = node;
                              }
                              break;
                          }
                      }
                  }
  
                  createCell(site);
                  var newArc = createBeach(site);
                  beaches.insert(lArc, newArc);
  
                  if (!lArc && !rArc)
                      return;
  
                  if (lArc === rArc) {
                      detachCircle(lArc);
                      rArc = createBeach(lArc.site);
                      beaches.insert(newArc, rArc);
                      newArc.edge = rArc.edge = createEdge(lArc.site, newArc.site);
                      attachCircle(lArc);
                      attachCircle(rArc);
                      return;
                  }
  
                  if (!rArc) { // && lArc
                      newArc.edge = createEdge(lArc.site, newArc.site);
                      return;
                  }
  
                  // else lArc !== rArc
                  detachCircle(lArc);
                  detachCircle(rArc);
  
                  var lSite = lArc.site,
                          ax = lSite[0],
                          ay = lSite[1],
                          bx = site[0] - ax,
                          by = site[1] - ay,
                          rSite = rArc.site,
                          cx = rSite[0] - ax,
                          cy = rSite[1] - ay,
                          d = 2 * (bx * cy - by * cx),
                          hb = bx * bx + by * by,
                          hc = cx * cx + cy * cy,
                          vertex = [(cy * hb - by * hc) / d + ax, (bx * hc - cx * hb) / d + ay];
  
                  setEdgeEnd(rArc.edge, lSite, rSite, vertex);
                  newArc.edge = createEdge(lSite, site, null, vertex);
                  rArc.edge = createEdge(site, rSite, null, vertex);
                  attachCircle(lArc);
                  attachCircle(rArc);
              }
  
              function leftBreakPoint(arc, directrix) {
                  var site = arc.site,
                          rfocx = site[0],
                          rfocy = site[1],
                          pby2 = rfocy - directrix;
  
                  if (!pby2)
                      return rfocx;
  
                  var lArc = arc.P;
                  if (!lArc)
                      return -Infinity;
  
                  site = lArc.site;
                  var lfocx = site[0],
                          lfocy = site[1],
                          plby2 = lfocy - directrix;
  
                  if (!plby2)
                      return lfocx;
  
                  var hl = lfocx - rfocx,
                          aby2 = 1 / pby2 - 1 / plby2,
                          b = hl / plby2;
  
                  if (aby2)
                      return (-b + Math.sqrt(b * b - 2 * aby2 * (hl * hl / (-2 * plby2) - lfocy + plby2 / 2 + rfocy - pby2 / 2))) / aby2 + rfocx;
  
                  return (rfocx + lfocx) / 2;
              }
  
              function rightBreakPoint(arc, directrix) {
                  var rArc = arc.N;
                  if (rArc)
                      return leftBreakPoint(rArc, directrix);
                  var site = arc.site;
                  return site[1] === directrix ? site[0] : Infinity;
              }
  
              var epsilon$4 = 1e-6;
              var epsilon2$2 = 1e-12;
              var beaches;
              var cells;
              var circles;
              var edges;
  
              function triangleArea(a, b, c) {
                  return (a[0] - c[0]) * (b[1] - a[1]) - (a[0] - b[0]) * (c[1] - a[1]);
              }
  
              function lexicographic(a, b) {
                  return b[1] - a[1]
                          || b[0] - a[0];
              }
  
              function Diagram(sites, extent) {
                  var site = sites.sort(lexicographic).pop(),
                          x,
                          y,
                          circle;
  
                  edges = [];
                  cells = new Array(sites.length);
                  beaches = new RedBlackTree;
                  circles = new RedBlackTree;
  
                  while (true) {
                      circle = firstCircle;
                      if (site && (!circle || site[1] < circle.y || (site[1] === circle.y && site[0] < circle.x))) {
                          if (site[0] !== x || site[1] !== y) {
                              addBeach(site);
                              x = site[0], y = site[1];
                          }
                          site = sites.pop();
                      } else if (circle) {
                          removeBeach(circle.arc);
                      } else {
                          break;
                      }
                  }
  
                  sortCellHalfedges();
  
                  if (extent) {
                      var x0 = +extent[0][0],
                              y0 = +extent[0][1],
                              x1 = +extent[1][0],
                              y1 = +extent[1][1];
                      clipEdges(x0, y0, x1, y1);
                      clipCells(x0, y0, x1, y1);
                  }
  
                  this.edges = edges;
                  this.cells = cells;
  
                  beaches =
                          circles =
                          edges =
                          cells = null;
              }
  
              Diagram.prototype = {
                  constructor: Diagram,
  
                  polygons: function () {
                      var edges = this.edges;
  
                      return this.cells.map(function (cell) {
                          var polygon = cell.halfedges.map(function (i) {
                              return cellHalfedgeStart(cell, edges[i]);
                          });
                          polygon.data = cell.site.data;
                          return polygon;
                      });
                  },
  
                  triangles: function () {
                      var triangles = [],
                              edges = this.edges;
  
                      this.cells.forEach(function (cell, i) {
                          if (!(m = (halfedges = cell.halfedges).length))
                              return;
                          var site = cell.site,
                                  halfedges,
                                  j = -1,
                                  m,
                                  s0,
                                  e1 = edges[halfedges[m - 1]],
                                  s1 = e1.left === site ? e1.right : e1.left;
  
                          while (++j < m) {
                              s0 = s1;
                              e1 = edges[halfedges[j]];
                              s1 = e1.left === site ? e1.right : e1.left;
                              if (s0 && s1 && i < s0.index && i < s1.index && triangleArea(site, s0, s1) < 0) {
                                  triangles.push([site.data, s0.data, s1.data]);
                              }
                          }
                      });
  
                      return triangles;
                  },
  
                  links: function () {
                      return this.edges.filter(function (edge) {
                          return edge.right;
                      }).map(function (edge) {
                          return {
                              source: edge.left.data,
                              target: edge.right.data
                          };
                      });
                  },
  
                  find: function (x, y, radius) {
                      var that = this, i0, i1 = that._found || 0, n = that.cells.length, cell;
  
                      // Use the previously-found cell, or start with an arbitrary one.
                      while (!(cell = that.cells[i1]))
                          if (++i1 >= n)
                              return null;
                      var dx = x - cell.site[0], dy = y - cell.site[1], d2 = dx * dx + dy * dy;
  
                      // Traverse the half-edges to find a closer cell, if any.
                      do {
                          cell = that.cells[i0 = i1], i1 = null;
                          cell.halfedges.forEach(function (e) {
                              var edge = that.edges[e], v = edge.left;
                              if ((v === cell.site || !v) && !(v = edge.right))
                                  return;
                              var vx = x - v[0], vy = y - v[1], v2 = vx * vx + vy * vy;
                              if (v2 < d2)
                                  d2 = v2, i1 = v.index;
                          });
                      } while (i1 !== null);
  
                      that._found = i0;
  
                      return radius == null || d2 <= radius * radius ? cell.site : null;
                  }
              };
  
              function voronoi() {
                  var x = x$4,
                          y = y$4,
                          extent = null;
  
                  function voronoi(data) {
                      return new Diagram(data.map(function (d, i) {
                          var s = [Math.round(x(d, i, data) / epsilon$4) * epsilon$4, Math.round(y(d, i, data) / epsilon$4) * epsilon$4];
                          s.index = i;
                          s.data = d;
                          return s;
                      }), extent);
                  }
  
                  voronoi.polygons = function (data) {
                      return voronoi(data).polygons();
                  };
  
                  voronoi.links = function (data) {
                      return voronoi(data).links();
                  };
  
                  voronoi.triangles = function (data) {
                      return voronoi(data).triangles();
                  };
  
                  voronoi.x = function (_) {
                      return arguments.length ? (x = typeof _ === "function" ? _ : constant$c(+_), voronoi) : x;
                  };
  
                  voronoi.y = function (_) {
                      return arguments.length ? (y = typeof _ === "function" ? _ : constant$c(+_), voronoi) : y;
                  };
  
                  voronoi.extent = function (_) {
                      return arguments.length ? (extent = _ == null ? null : [[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]], voronoi) : extent && [[extent[0][0], extent[0][1]], [extent[1][0], extent[1][1]]];
                  };
  
                  voronoi.size = function (_) {
                      return arguments.length ? (extent = _ == null ? null : [[0, 0], [+_[0], +_[1]]], voronoi) : extent && [extent[1][0] - extent[0][0], extent[1][1] - extent[0][1]];
                  };
  
                  return voronoi;
              }
  
              function constant$d(x) {
                  return function () {
                      return x;
                  };
              }
  
              function ZoomEvent(target, type, transform) {
                  this.target = target;
                  this.type = type;
                  this.transform = transform;
              }
  
              function Transform(k, x, y) {
                  this.k = k;
                  this.x = x;
                  this.y = y;
              }
  
              Transform.prototype = {
                  constructor: Transform,
                  scale: function (k) {
                      return k === 1 ? this : new Transform(this.k * k, this.x, this.y);
                  },
                  translate: function (x, y) {
                      return x === 0 & y === 0 ? this : new Transform(this.k, this.x + this.k * x, this.y + this.k * y);
                  },
                  apply: function (point) {
                      return [point[0] * this.k + this.x, point[1] * this.k + this.y];
                  },
                  applyX: function (x) {
                      return x * this.k + this.x;
                  },
                  applyY: function (y) {
                      return y * this.k + this.y;
                  },
                  invert: function (location) {
                      return [(location[0] - this.x) / this.k, (location[1] - this.y) / this.k];
                  },
                  invertX: function (x) {
                      return (x - this.x) / this.k;
                  },
                  invertY: function (y) {
                      return (y - this.y) / this.k;
                  },
                  rescaleX: function (x) {
                      return x.copy().domain(x.range().map(this.invertX, this).map(x.invert, x));
                  },
                  rescaleY: function (y) {
                      return y.copy().domain(y.range().map(this.invertY, this).map(y.invert, y));
                  },
                  toString: function () {
                      return "translate(" + this.x + "," + this.y + ") scale(" + this.k + ")";
                  }
              };
  
              var identity$9 = new Transform(1, 0, 0);
  
              transform$1.prototype = Transform.prototype;
  
              function transform$1(node) {
                  while (!node.__zoom)
                      if (!(node = node.parentNode))
                          return identity$9;
                  return node.__zoom;
              }
  
              function nopropagation$2() {
                  exports.event.stopImmediatePropagation();
              }
  
              function noevent$2() {
                  exports.event.preventDefault();
                  exports.event.stopImmediatePropagation();
              }
  
  // Ignore right-click, since that should open the context menu.
              function defaultFilter$2() {
                  return !exports.event.ctrlKey && !exports.event.button;
              }
  
              function defaultExtent$1() {
                  var e = this;
                  if (e instanceof SVGElement) {
                      e = e.ownerSVGElement || e;
                      if (e.hasAttribute("viewBox")) {
                          e = e.viewBox.baseVal;
                          return [[e.x, e.y], [e.x + e.width, e.y + e.height]];
                      }
                      return [[0, 0], [e.width.baseVal.value, e.height.baseVal.value]];
                  }
                  return [[0, 0], [e.clientWidth, e.clientHeight]];
              }
  
              function defaultTransform() {
                  return this.__zoom || identity$9;
              }
  
              function defaultWheelDelta() {
                  return -exports.event.deltaY * (exports.event.deltaMode === 1 ? 0.05 : exports.event.deltaMode ? 1 : 0.002);
              }
  
              function defaultTouchable$2() {
                  return navigator.maxTouchPoints || ("ontouchstart" in this);
              }
  
              function defaultConstrain(transform, extent, translateExtent) {
                  var dx0 = transform.invertX(extent[0][0]) - translateExtent[0][0],
                          dx1 = transform.invertX(extent[1][0]) - translateExtent[1][0],
                          dy0 = transform.invertY(extent[0][1]) - translateExtent[0][1],
                          dy1 = transform.invertY(extent[1][1]) - translateExtent[1][1];
                  return transform.translate(
                          dx1 > dx0 ? (dx0 + dx1) / 2 : Math.min(0, dx0) || Math.max(0, dx1),
                          dy1 > dy0 ? (dy0 + dy1) / 2 : Math.min(0, dy0) || Math.max(0, dy1)
                          );
              }
  
              function zoom() {
                  var filter = defaultFilter$2,
                          extent = defaultExtent$1,
                          constrain = defaultConstrain,
                          wheelDelta = defaultWheelDelta,
                          touchable = defaultTouchable$2,
                          scaleExtent = [0, Infinity],
                          translateExtent = [[-Infinity, -Infinity], [Infinity, Infinity]],
                          duration = 250,
                          interpolate = interpolateZoom,
                          listeners = dispatch("start", "zoom", "end"),
                          touchstarting,
                          touchending,
                          touchDelay = 500,
                          wheelDelay = 150,
                          clickDistance2 = 0;
  
                  function zoom(selection) {
                      selection
                              .property("__zoom", defaultTransform)
                              .on("wheel.zoom", wheeled)
                              .on("mousedown.zoom", mousedowned)
                              .on("dblclick.zoom", dblclicked)
                              .filter(touchable)
                              .on("touchstart.zoom", touchstarted)
                              .on("touchmove.zoom", touchmoved)
                              .on("touchend.zoom touchcancel.zoom", touchended)
                              .style("touch-action", "none")
                              .style("-webkit-tap-highlight-color", "rgba(0,0,0,0)");
                  }
  
                  zoom.transform = function (collection, transform, point) {
                      var selection = collection.selection ? collection.selection() : collection;
                      selection.property("__zoom", defaultTransform);
                      if (collection !== selection) {
                          schedule(collection, transform, point);
                      } else {
                          selection.interrupt().each(function () {
                              gesture(this, arguments)
                                      .start()
                                      .zoom(null, typeof transform === "function" ? transform.apply(this, arguments) : transform)
                                      .end();
                          });
                      }
                  };
  
                  zoom.scaleBy = function (selection, k, p) {
                      zoom.scaleTo(selection, function () {
                          var k0 = this.__zoom.k,
                                  k1 = typeof k === "function" ? k.apply(this, arguments) : k;
                          return k0 * k1;
                      }, p);
                  };
  
                  zoom.scaleTo = function (selection, k, p) {
                      zoom.transform(selection, function () {
                          var e = extent.apply(this, arguments),
                                  t0 = this.__zoom,
                                  p0 = p == null ? centroid(e) : typeof p === "function" ? p.apply(this, arguments) : p,
                                  p1 = t0.invert(p0),
                                  k1 = typeof k === "function" ? k.apply(this, arguments) : k;
                          return constrain(translate(scale(t0, k1), p0, p1), e, translateExtent);
                      }, p);
                  };
  
                  zoom.translateBy = function (selection, x, y) {
                      zoom.transform(selection, function () {
                          return constrain(this.__zoom.translate(
                                  typeof x === "function" ? x.apply(this, arguments) : x,
                                  typeof y === "function" ? y.apply(this, arguments) : y
                                  ), extent.apply(this, arguments), translateExtent);
                      });
                  };
  
                  zoom.translateTo = function (selection, x, y, p) {
                      zoom.transform(selection, function () {
                          var e = extent.apply(this, arguments),
                                  t = this.__zoom,
                                  p0 = p == null ? centroid(e) : typeof p === "function" ? p.apply(this, arguments) : p;
                          return constrain(identity$9.translate(p0[0], p0[1]).scale(t.k).translate(
                                  typeof x === "function" ? -x.apply(this, arguments) : -x,
                                  typeof y === "function" ? -y.apply(this, arguments) : -y
                                  ), e, translateExtent);
                      }, p);
                  };
  
                  function scale(transform, k) {
                      k = Math.max(scaleExtent[0], Math.min(scaleExtent[1], k));
                      return k === transform.k ? transform : new Transform(k, transform.x, transform.y);
                  }
  
                  function translate(transform, p0, p1) {
                      var x = p0[0] - p1[0] * transform.k, y = p0[1] - p1[1] * transform.k;
                      return x === transform.x && y === transform.y ? transform : new Transform(transform.k, x, y);
                  }
  
                  function centroid(extent) {
                      return [(+extent[0][0] + +extent[1][0]) / 2, (+extent[0][1] + +extent[1][1]) / 2];
                  }
  
                  function schedule(transition, transform, point) {
                      transition
                              .on("start.zoom", function () {
                                  gesture(this, arguments).start();
                              })
                              .on("interrupt.zoom end.zoom", function () {
                                  gesture(this, arguments).end();
                              })
                              .tween("zoom", function () {
                                  var that = this,
                                          args = arguments,
                                          g = gesture(that, args),
                                          e = extent.apply(that, args),
                                          p = point == null ? centroid(e) : typeof point === "function" ? point.apply(that, args) : point,
                                          w = Math.max(e[1][0] - e[0][0], e[1][1] - e[0][1]),
                                          a = that.__zoom,
                                          b = typeof transform === "function" ? transform.apply(that, args) : transform,
                                          i = interpolate(a.invert(p).concat(w / a.k), b.invert(p).concat(w / b.k));
                                  return function (t) {
                                      if (t === 1)
                                          t = b; // Avoid rounding error on end.
                                      else {
                                          var l = i(t), k = w / l[2];
                                          t = new Transform(k, p[0] - l[0] * k, p[1] - l[1] * k);
                                      }
                                      g.zoom(null, t);
                                  };
                              });
                  }
  
                  function gesture(that, args, clean) {
                      return (!clean && that.__zooming) || new Gesture(that, args);
                  }
  
                  function Gesture(that, args) {
                      this.that = that;
                      this.args = args;
                      this.active = 0;
                      this.extent = extent.apply(that, args);
                      this.taps = 0;
                  }
  
                  Gesture.prototype = {
                      start: function () {
                          if (++this.active === 1) {
                              this.that.__zooming = this;
                              this.emit("start");
                          }
                          return this;
                      },
                      zoom: function (key, transform) {
                          if (this.mouse && key !== "mouse")
                              this.mouse[1] = transform.invert(this.mouse[0]);
                          if (this.touch0 && key !== "touch")
                              this.touch0[1] = transform.invert(this.touch0[0]);
                          if (this.touch1 && key !== "touch")
                              this.touch1[1] = transform.invert(this.touch1[0]);
                          this.that.__zoom = transform;
                          this.emit("zoom");
                          return this;
                      },
                      end: function () {
                          if (--this.active === 0) {
                              delete this.that.__zooming;
                              this.emit("end");
                          }
                          return this;
                      },
                      emit: function (type) {
                          customEvent(new ZoomEvent(zoom, type, this.that.__zoom), listeners.apply, listeners, [type, this.that, this.args]);
                      }
                  };
  
                  function wheeled() {
                      if (!filter.apply(this, arguments))
                          return;
                      var g = gesture(this, arguments),
                              t = this.__zoom,
                              k = Math.max(scaleExtent[0], Math.min(scaleExtent[1], t.k * Math.pow(2, wheelDelta.apply(this, arguments)))),
                              p = mouse(this);
  
                      // If the mouse is in the same location as before, reuse it.
                      // If there were recent wheel events, reset the wheel idle timeout.
                      if (g.wheel) {
                          if (g.mouse[0][0] !== p[0] || g.mouse[0][1] !== p[1]) {
                              g.mouse[1] = t.invert(g.mouse[0] = p);
                          }
                          clearTimeout(g.wheel);
                      }
  
                      // If this wheel event won’t trigger a transform change, ignore it.
                      else if (t.k === k)
                          return;
  
                      // Otherwise, capture the mouse point and location at the start.
                      else {
                          g.mouse = [p, t.invert(p)];
                          interrupt(this);
                          g.start();
                      }
  
                      noevent$2();
                      g.wheel = setTimeout(wheelidled, wheelDelay);
                      g.zoom("mouse", constrain(translate(scale(t, k), g.mouse[0], g.mouse[1]), g.extent, translateExtent));
  
                      function wheelidled() {
                          g.wheel = null;
                          g.end();
                      }
                  }
  
                  function mousedowned() {
                      if (touchending || !filter.apply(this, arguments))
                          return;
                      var g = gesture(this, arguments, true),
                              v = select(exports.event.view).on("mousemove.zoom", mousemoved, true).on("mouseup.zoom", mouseupped, true),
                              p = mouse(this),
                              x0 = exports.event.clientX,
                              y0 = exports.event.clientY;
  
                      dragDisable(exports.event.view);
                      nopropagation$2();
                      g.mouse = [p, this.__zoom.invert(p)];
                      interrupt(this);
                      g.start();
  
                      function mousemoved() {
                          noevent$2();
                          if (!g.moved) {
                              var dx = exports.event.clientX - x0, dy = exports.event.clientY - y0;
                              g.moved = dx * dx + dy * dy > clickDistance2;
                          }
                          g.zoom("mouse", constrain(translate(g.that.__zoom, g.mouse[0] = mouse(g.that), g.mouse[1]), g.extent, translateExtent));
                      }
  
                      function mouseupped() {
                          v.on("mousemove.zoom mouseup.zoom", null);
                          yesdrag(exports.event.view, g.moved);
                          noevent$2();
                          g.end();
                      }
                  }
  
                  function dblclicked() {
                      if (!filter.apply(this, arguments))
                          return;
                      var t0 = this.__zoom,
                              p0 = mouse(this),
                              p1 = t0.invert(p0),
                              k1 = t0.k * (exports.event.shiftKey ? 0.5 : 2),
                              t1 = constrain(translate(scale(t0, k1), p0, p1), extent.apply(this, arguments), translateExtent);
  
                      noevent$2();
                      if (duration > 0)
                          select(this).transition().duration(duration).call(schedule, t1, p0);
                      else
                          select(this).call(zoom.transform, t1);
                  }
  
                  function touchstarted() {
                      if (!filter.apply(this, arguments))
                          return;
                      var touches = exports.event.touches,
                              n = touches.length,
                              g = gesture(this, arguments, exports.event.changedTouches.length === n),
                              started, i, t, p;
  
                      nopropagation$2();
                      for (i = 0; i < n; ++i) {
                          t = touches[i], p = touch(this, touches, t.identifier);
                          p = [p, this.__zoom.invert(p), t.identifier];
                          if (!g.touch0)
                              g.touch0 = p, started = true, g.taps = 1 + !!touchstarting;
                          else if (!g.touch1 && g.touch0[2] !== p[2])
                              g.touch1 = p, g.taps = 0;
                      }
  
                      if (touchstarting)
                          touchstarting = clearTimeout(touchstarting);
  
                      if (started) {
                          if (g.taps < 2)
                              touchstarting = setTimeout(function () {
                                  touchstarting = null;
                              }, touchDelay);
                          interrupt(this);
                          g.start();
                      }
                  }
  
                  function touchmoved() {
                      if (!this.__zooming)
                          return;
                      var g = gesture(this, arguments),
                              touches = exports.event.changedTouches,
                              n = touches.length, i, t, p, l;
  
                      noevent$2();
                      if (touchstarting)
                          touchstarting = clearTimeout(touchstarting);
                      g.taps = 0;
                      for (i = 0; i < n; ++i) {
                          t = touches[i], p = touch(this, touches, t.identifier);
                          if (g.touch0 && g.touch0[2] === t.identifier)
                              g.touch0[0] = p;
                          else if (g.touch1 && g.touch1[2] === t.identifier)
                              g.touch1[0] = p;
                      }
                      t = g.that.__zoom;
                      if (g.touch1) {
                          var p0 = g.touch0[0], l0 = g.touch0[1],
                                  p1 = g.touch1[0], l1 = g.touch1[1],
                                  dp = (dp = p1[0] - p0[0]) * dp + (dp = p1[1] - p0[1]) * dp,
                                  dl = (dl = l1[0] - l0[0]) * dl + (dl = l1[1] - l0[1]) * dl;
                          t = scale(t, Math.sqrt(dp / dl));
                          p = [(p0[0] + p1[0]) / 2, (p0[1] + p1[1]) / 2];
                          l = [(l0[0] + l1[0]) / 2, (l0[1] + l1[1]) / 2];
                      } else if (g.touch0)
                          p = g.touch0[0], l = g.touch0[1];
                      else
                          return;
                      g.zoom("touch", constrain(translate(t, p, l), g.extent, translateExtent));
                  }
  
                  function touchended() {
                      if (!this.__zooming)
                          return;
                      var g = gesture(this, arguments),
                              touches = exports.event.changedTouches,
                              n = touches.length, i, t;
  
                      nopropagation$2();
                      if (touchending)
                          clearTimeout(touchending);
                      touchending = setTimeout(function () {
                          touchending = null;
                      }, touchDelay);
                      for (i = 0; i < n; ++i) {
                          t = touches[i];
                          if (g.touch0 && g.touch0[2] === t.identifier)
                              delete g.touch0;
                          else if (g.touch1 && g.touch1[2] === t.identifier)
                              delete g.touch1;
                      }
                      if (g.touch1 && !g.touch0)
                          g.touch0 = g.touch1, delete g.touch1;
                      if (g.touch0)
                          g.touch0[1] = this.__zoom.invert(g.touch0[0]);
                      else {
                          g.end();
                          // If this was a dbltap, reroute to the (optional) dblclick.zoom handler.
                          if (g.taps === 2) {
                              var p = select(this).on("dblclick.zoom");
                              if (p)
                                  p.apply(this, arguments);
                          }
                      }
                  }
  
                  zoom.wheelDelta = function (_) {
                      return arguments.length ? (wheelDelta = typeof _ === "function" ? _ : constant$d(+_), zoom) : wheelDelta;
                  };
  
                  zoom.filter = function (_) {
                      return arguments.length ? (filter = typeof _ === "function" ? _ : constant$d(!!_), zoom) : filter;
                  };
  
                  zoom.touchable = function (_) {
                      return arguments.length ? (touchable = typeof _ === "function" ? _ : constant$d(!!_), zoom) : touchable;
                  };
  
                  zoom.extent = function (_) {
                      return arguments.length ? (extent = typeof _ === "function" ? _ : constant$d([[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]]), zoom) : extent;
                  };
  
                  zoom.scaleExtent = function (_) {
                      return arguments.length ? (scaleExtent[0] = +_[0], scaleExtent[1] = +_[1], zoom) : [scaleExtent[0], scaleExtent[1]];
                  };
  
                  zoom.translateExtent = function (_) {
                      return arguments.length ? (translateExtent[0][0] = +_[0][0], translateExtent[1][0] = +_[1][0], translateExtent[0][1] = +_[0][1], translateExtent[1][1] = +_[1][1], zoom) : [[translateExtent[0][0], translateExtent[0][1]], [translateExtent[1][0], translateExtent[1][1]]];
                  };
  
                  zoom.constrain = function (_) {
                      return arguments.length ? (constrain = _, zoom) : constrain;
                  };
  
                  zoom.duration = function (_) {
                      return arguments.length ? (duration = +_, zoom) : duration;
                  };
  
                  zoom.interpolate = function (_) {
                      return arguments.length ? (interpolate = _, zoom) : interpolate;
                  };
  
                  zoom.on = function () {
                      var value = listeners.on.apply(listeners, arguments);
                      return value === listeners ? zoom : value;
                  };
  
                  zoom.clickDistance = function (_) {
                      return arguments.length ? (clickDistance2 = (_ = +_) * _, zoom) : Math.sqrt(clickDistance2);
                  };
  
                  return zoom;
              }
  
              exports.FormatSpecifier = FormatSpecifier;
              exports.active = active;
              exports.arc = arc;
              exports.area = area$3;
              exports.areaRadial = areaRadial;
              exports.ascending = ascending;
              exports.autoType = autoType;
              exports.axisBottom = axisBottom;
              exports.axisLeft = axisLeft;
              exports.axisRight = axisRight;
              exports.axisTop = axisTop;
              exports.bisect = bisectRight;
              exports.bisectLeft = bisectLeft;
              exports.bisectRight = bisectRight;
              exports.bisector = bisector;
              exports.blob = blob;
              exports.brush = brush;
              exports.brushSelection = brushSelection;
              exports.brushX = brushX;
              exports.brushY = brushY;
              exports.buffer = buffer;
              exports.chord = chord;
              exports.clientPoint = point;
              exports.cluster = cluster;
              exports.color = color;
              exports.contourDensity = density;
              exports.contours = contours;
              exports.create = create;
              exports.creator = creator;
              exports.cross = cross;
              exports.csv = csv$1;
              exports.csvFormat = csvFormat;
              exports.csvFormatBody = csvFormatBody;
              exports.csvFormatRow = csvFormatRow;
              exports.csvFormatRows = csvFormatRows;
              exports.csvFormatValue = csvFormatValue;
              exports.csvParse = csvParse;
              exports.csvParseRows = csvParseRows;
              exports.cubehelix = cubehelix;
              exports.curveBasis = basis$2;
              exports.curveBasisClosed = basisClosed$1;
              exports.curveBasisOpen = basisOpen;
              exports.curveBundle = bundle;
              exports.curveCardinal = cardinal;
              exports.curveCardinalClosed = cardinalClosed;
              exports.curveCardinalOpen = cardinalOpen;
              exports.curveCatmullRom = catmullRom;
              exports.curveCatmullRomClosed = catmullRomClosed;
              exports.curveCatmullRomOpen = catmullRomOpen;
              exports.curveLinear = curveLinear;
              exports.curveLinearClosed = linearClosed;
              exports.curveMonotoneX = monotoneX;
              exports.curveMonotoneY = monotoneY;
              exports.curveNatural = natural;
              exports.curveStep = step;
              exports.curveStepAfter = stepAfter;
              exports.curveStepBefore = stepBefore;
              exports.customEvent = customEvent;
              exports.descending = descending;
              exports.deviation = deviation;
              exports.dispatch = dispatch;
              exports.drag = drag;
              exports.dragDisable = dragDisable;
              exports.dragEnable = yesdrag;
              exports.dsv = dsv;
              exports.dsvFormat = dsvFormat;
              exports.easeBack = backInOut;
              exports.easeBackIn = backIn;
              exports.easeBackInOut = backInOut;
              exports.easeBackOut = backOut;
              exports.easeBounce = bounceOut;
              exports.easeBounceIn = bounceIn;
              exports.easeBounceInOut = bounceInOut;
              exports.easeBounceOut = bounceOut;
              exports.easeCircle = circleInOut;
              exports.easeCircleIn = circleIn;
              exports.easeCircleInOut = circleInOut;
              exports.easeCircleOut = circleOut;
              exports.easeCubic = cubicInOut;
              exports.easeCubicIn = cubicIn;
              exports.easeCubicInOut = cubicInOut;
              exports.easeCubicOut = cubicOut;
              exports.easeElastic = elasticOut;
              exports.easeElasticIn = elasticIn;
              exports.easeElasticInOut = elasticInOut;
              exports.easeElasticOut = elasticOut;
              exports.easeExp = expInOut;
              exports.easeExpIn = expIn;
              exports.easeExpInOut = expInOut;
              exports.easeExpOut = expOut;
              exports.easeLinear = linear$1;
              exports.easePoly = polyInOut;
              exports.easePolyIn = polyIn;
              exports.easePolyInOut = polyInOut;
              exports.easePolyOut = polyOut;
              exports.easeQuad = quadInOut;
              exports.easeQuadIn = quadIn;
              exports.easeQuadInOut = quadInOut;
              exports.easeQuadOut = quadOut;
              exports.easeSin = sinInOut;
              exports.easeSinIn = sinIn;
              exports.easeSinInOut = sinInOut;
              exports.easeSinOut = sinOut;
              exports.entries = entries;
              exports.extent = extent;
              exports.forceCenter = center$1;
              exports.forceCollide = collide;
              exports.forceLink = link;
              exports.forceManyBody = manyBody;
              exports.forceRadial = radial;
              exports.forceSimulation = simulation;
              exports.forceX = x$2;
              exports.forceY = y$2;
              exports.formatDefaultLocale = defaultLocale;
              exports.formatLocale = formatLocale;
              exports.formatSpecifier = formatSpecifier;
              exports.geoAlbers = albers;
              exports.geoAlbersUsa = albersUsa;
              exports.geoArea = area$1;
              exports.geoAzimuthalEqualArea = azimuthalEqualArea;
              exports.geoAzimuthalEqualAreaRaw = azimuthalEqualAreaRaw;
              exports.geoAzimuthalEquidistant = azimuthalEquidistant;
              exports.geoAzimuthalEquidistantRaw = azimuthalEquidistantRaw;
              exports.geoBounds = bounds;
              exports.geoCentroid = centroid;
              exports.geoCircle = circle;
              exports.geoClipAntimeridian = clipAntimeridian;
              exports.geoClipCircle = clipCircle;
              exports.geoClipExtent = extent$1;
              exports.geoClipRectangle = clipRectangle;
              exports.geoConicConformal = conicConformal;
              exports.geoConicConformalRaw = conicConformalRaw;
              exports.geoConicEqualArea = conicEqualArea;
              exports.geoConicEqualAreaRaw = conicEqualAreaRaw;
              exports.geoConicEquidistant = conicEquidistant;
              exports.geoConicEquidistantRaw = conicEquidistantRaw;
              exports.geoContains = contains$1;
              exports.geoDistance = distance;
              exports.geoEqualEarth = equalEarth;
              exports.geoEqualEarthRaw = equalEarthRaw;
              exports.geoEquirectangular = equirectangular;
              exports.geoEquirectangularRaw = equirectangularRaw;
              exports.geoGnomonic = gnomonic;
              exports.geoGnomonicRaw = gnomonicRaw;
              exports.geoGraticule = graticule;
              exports.geoGraticule10 = graticule10;
              exports.geoIdentity = identity$5;
              exports.geoInterpolate = interpolate$1;
              exports.geoLength = length$1;
              exports.geoMercator = mercator;
              exports.geoMercatorRaw = mercatorRaw;
              exports.geoNaturalEarth1 = naturalEarth1;
              exports.geoNaturalEarth1Raw = naturalEarth1Raw;
              exports.geoOrthographic = orthographic;
              exports.geoOrthographicRaw = orthographicRaw;
              exports.geoPath = index$1;
              exports.geoProjection = projection;
              exports.geoProjectionMutator = projectionMutator;
              exports.geoRotation = rotation;
              exports.geoStereographic = stereographic;
              exports.geoStereographicRaw = stereographicRaw;
              exports.geoStream = geoStream;
              exports.geoTransform = transform;
              exports.geoTransverseMercator = transverseMercator;
              exports.geoTransverseMercatorRaw = transverseMercatorRaw;
              exports.gray = gray;
              exports.hcl = hcl;
              exports.hierarchy = hierarchy;
              exports.histogram = histogram;
              exports.hsl = hsl;
              exports.html = html;
              exports.image = image;
              exports.interpolate = interpolateValue;
              exports.interpolateArray = array$1;
              exports.interpolateBasis = basis$1;
              exports.interpolateBasisClosed = basisClosed;
              exports.interpolateBlues = Blues;
              exports.interpolateBrBG = BrBG;
              exports.interpolateBuGn = BuGn;
              exports.interpolateBuPu = BuPu;
              exports.interpolateCividis = cividis;
              exports.interpolateCool = cool;
              exports.interpolateCubehelix = cubehelix$2;
              exports.interpolateCubehelixDefault = cubehelix$3;
              exports.interpolateCubehelixLong = cubehelixLong;
              exports.interpolateDate = date;
              exports.interpolateDiscrete = discrete;
              exports.interpolateGnBu = GnBu;
              exports.interpolateGreens = Greens;
              exports.interpolateGreys = Greys;
              exports.interpolateHcl = hcl$2;
              exports.interpolateHclLong = hclLong;
              exports.interpolateHsl = hsl$2;
              exports.interpolateHslLong = hslLong;
              exports.interpolateHue = hue$1;
              exports.interpolateInferno = inferno;
              exports.interpolateLab = lab$1;
              exports.interpolateMagma = magma;
              exports.interpolateNumber = interpolateNumber;
              exports.interpolateNumberArray = numberArray;
              exports.interpolateObject = object;
              exports.interpolateOrRd = OrRd;
              exports.interpolateOranges = Oranges;
              exports.interpolatePRGn = PRGn;
              exports.interpolatePiYG = PiYG;
              exports.interpolatePlasma = plasma;
              exports.interpolatePuBu = PuBu;
              exports.interpolatePuBuGn = PuBuGn;
              exports.interpolatePuOr = PuOr;
              exports.interpolatePuRd = PuRd;
              exports.interpolatePurples = Purples;
              exports.interpolateRainbow = rainbow;
              exports.interpolateRdBu = RdBu;
              exports.interpolateRdGy = RdGy;
              exports.interpolateRdPu = RdPu;
              exports.interpolateRdYlBu = RdYlBu;
              exports.interpolateRdYlGn = RdYlGn;
              exports.interpolateReds = Reds;
              exports.interpolateRgb = interpolateRgb;
              exports.interpolateRgbBasis = rgbBasis;
              exports.interpolateRgbBasisClosed = rgbBasisClosed;
              exports.interpolateRound = interpolateRound;
              exports.interpolateSinebow = sinebow;
              exports.interpolateSpectral = Spectral;
              exports.interpolateString = interpolateString;
              exports.interpolateTransformCss = interpolateTransformCss;
              exports.interpolateTransformSvg = interpolateTransformSvg;
              exports.interpolateTurbo = turbo;
              exports.interpolateViridis = viridis;
              exports.interpolateWarm = warm;
              exports.interpolateYlGn = YlGn;
              exports.interpolateYlGnBu = YlGnBu;
              exports.interpolateYlOrBr = YlOrBr;
              exports.interpolateYlOrRd = YlOrRd;
              exports.interpolateZoom = interpolateZoom;
              exports.interrupt = interrupt;
              exports.interval = interval$1;
              exports.isoFormat = formatIso;
              exports.isoParse = parseIso;
              exports.json = json;
              exports.keys = keys;
              exports.lab = lab;
              exports.lch = lch;
              exports.line = line;
              exports.lineRadial = lineRadial$1;
              exports.linkHorizontal = linkHorizontal;
              exports.linkRadial = linkRadial;
              exports.linkVertical = linkVertical;
              exports.local = local;
              exports.map = map$1;
              exports.matcher = matcher;
              exports.max = max;
              exports.mean = mean;
              exports.median = median;
              exports.merge = merge;
              exports.min = min;
              exports.mouse = mouse;
              exports.namespace = namespace;
              exports.namespaces = namespaces;
              exports.nest = nest;
              exports.now = now;
              exports.pack = index$2;
              exports.packEnclose = enclose;
              exports.packSiblings = siblings;
              exports.pairs = pairs;
              exports.partition = partition;
              exports.path = path;
              exports.permute = permute;
              exports.pie = pie;
              exports.piecewise = piecewise;
              exports.pointRadial = pointRadial;
              exports.polygonArea = area$2;
              exports.polygonCentroid = centroid$1;
              exports.polygonContains = contains$2;
              exports.polygonHull = hull;
              exports.polygonLength = length$2;
              exports.precisionFixed = precisionFixed;
              exports.precisionPrefix = precisionPrefix;
              exports.precisionRound = precisionRound;
              exports.quadtree = quadtree;
              exports.quantile = threshold;
              exports.quantize = quantize;
              exports.radialArea = areaRadial;
              exports.radialLine = lineRadial$1;
              exports.randomBates = bates;
              exports.randomExponential = exponential$1;
              exports.randomIrwinHall = irwinHall;
              exports.randomLogNormal = logNormal;
              exports.randomNormal = normal;
              exports.randomUniform = uniform;
              exports.range = sequence;
              exports.rgb = rgb;
              exports.ribbon = ribbon;
              exports.scaleBand = band;
              exports.scaleDiverging = diverging;
              exports.scaleDivergingLog = divergingLog;
              exports.scaleDivergingPow = divergingPow;
              exports.scaleDivergingSqrt = divergingSqrt;
              exports.scaleDivergingSymlog = divergingSymlog;
              exports.scaleIdentity = identity$7;
              exports.scaleImplicit = implicit;
              exports.scaleLinear = linear$2;
              exports.scaleLog = log$1;
              exports.scaleOrdinal = ordinal;
              exports.scalePoint = point$1;
              exports.scalePow = pow$1;
              exports.scaleQuantile = quantile;
              exports.scaleQuantize = quantize$1;
              exports.scaleSequential = sequential;
              exports.scaleSequentialLog = sequentialLog;
              exports.scaleSequentialPow = sequentialPow;
              exports.scaleSequentialQuantile = sequentialQuantile;
              exports.scaleSequentialSqrt = sequentialSqrt;
              exports.scaleSequentialSymlog = sequentialSymlog;
              exports.scaleSqrt = sqrt$1;
              exports.scaleSymlog = symlog;
              exports.scaleThreshold = threshold$1;
              exports.scaleTime = time;
              exports.scaleUtc = utcTime;
              exports.scan = scan;
              exports.schemeAccent = Accent;
              exports.schemeBlues = scheme$l;
              exports.schemeBrBG = scheme;
              exports.schemeBuGn = scheme$9;
              exports.schemeBuPu = scheme$a;
              exports.schemeCategory10 = category10;
              exports.schemeDark2 = Dark2;
              exports.schemeGnBu = scheme$b;
              exports.schemeGreens = scheme$m;
              exports.schemeGreys = scheme$n;
              exports.schemeOrRd = scheme$c;
              exports.schemeOranges = scheme$q;
              exports.schemePRGn = scheme$1;
              exports.schemePaired = Paired;
              exports.schemePastel1 = Pastel1;
              exports.schemePastel2 = Pastel2;
              exports.schemePiYG = scheme$2;
              exports.schemePuBu = scheme$e;
              exports.schemePuBuGn = scheme$d;
              exports.schemePuOr = scheme$3;
              exports.schemePuRd = scheme$f;
              exports.schemePurples = scheme$o;
              exports.schemeRdBu = scheme$4;
              exports.schemeRdGy = scheme$5;
              exports.schemeRdPu = scheme$g;
              exports.schemeRdYlBu = scheme$6;
              exports.schemeRdYlGn = scheme$7;
              exports.schemeReds = scheme$p;
              exports.schemeSet1 = Set1;
              exports.schemeSet2 = Set2;
              exports.schemeSet3 = Set3;
              exports.schemeSpectral = scheme$8;
              exports.schemeTableau10 = Tableau10;
              exports.schemeYlGn = scheme$i;
              exports.schemeYlGnBu = scheme$h;
              exports.schemeYlOrBr = scheme$j;
              exports.schemeYlOrRd = scheme$k;
              exports.select = select;
              exports.selectAll = selectAll;
              exports.selection = selection;
              exports.selector = selector;
              exports.selectorAll = selectorAll;
              exports.set = set$2;
              exports.shuffle = shuffle;
              exports.stack = stack;
              exports.stackOffsetDiverging = diverging$1;
              exports.stackOffsetExpand = expand;
              exports.stackOffsetNone = none$1;
              exports.stackOffsetSilhouette = silhouette;
              exports.stackOffsetWiggle = wiggle;
              exports.stackOrderAppearance = appearance;
              exports.stackOrderAscending = ascending$3;
              exports.stackOrderDescending = descending$2;
              exports.stackOrderInsideOut = insideOut;
              exports.stackOrderNone = none$2;
              exports.stackOrderReverse = reverse;
              exports.stratify = stratify;
              exports.style = styleValue;
              exports.sum = sum;
              exports.svg = svg;
              exports.symbol = symbol;
              exports.symbolCircle = circle$2;
              exports.symbolCross = cross$2;
              exports.symbolDiamond = diamond;
              exports.symbolSquare = square;
              exports.symbolStar = star;
              exports.symbolTriangle = triangle;
              exports.symbolWye = wye;
              exports.symbols = symbols;
              exports.text = text;
              exports.thresholdFreedmanDiaconis = freedmanDiaconis;
              exports.thresholdScott = scott;
              exports.thresholdSturges = thresholdSturges;
              exports.tickFormat = tickFormat;
              exports.tickIncrement = tickIncrement;
              exports.tickStep = tickStep;
              exports.ticks = ticks;
              exports.timeDay = day;
              exports.timeDays = days;
              exports.timeFormatDefaultLocale = defaultLocale$1;
              exports.timeFormatLocale = formatLocale$1;
              exports.timeFriday = friday;
              exports.timeFridays = fridays;
              exports.timeHour = hour;
              exports.timeHours = hours;
              exports.timeInterval = newInterval;
              exports.timeMillisecond = millisecond;
              exports.timeMilliseconds = milliseconds;
              exports.timeMinute = minute;
              exports.timeMinutes = minutes;
              exports.timeMonday = monday;
              exports.timeMondays = mondays;
              exports.timeMonth = month;
              exports.timeMonths = months;
              exports.timeSaturday = saturday;
              exports.timeSaturdays = saturdays;
              exports.timeSecond = second;
              exports.timeSeconds = seconds;
              exports.timeSunday = sunday;
              exports.timeSundays = sundays;
              exports.timeThursday = thursday;
              exports.timeThursdays = thursdays;
              exports.timeTuesday = tuesday;
              exports.timeTuesdays = tuesdays;
              exports.timeWednesday = wednesday;
              exports.timeWednesdays = wednesdays;
              exports.timeWeek = sunday;
              exports.timeWeeks = sundays;
              exports.timeYear = year;
              exports.timeYears = years;
              exports.timeout = timeout$1;
              exports.timer = timer;
              exports.timerFlush = timerFlush;
              exports.touch = touch;
              exports.touches = touches;
              exports.transition = transition;
              exports.transpose = transpose;
              exports.tree = tree;
              exports.treemap = index$3;
              exports.treemapBinary = binary;
              exports.treemapDice = treemapDice;
              exports.treemapResquarify = resquarify;
              exports.treemapSlice = treemapSlice;
              exports.treemapSliceDice = sliceDice;
              exports.treemapSquarify = squarify;
              exports.tsv = tsv$1;
              exports.tsvFormat = tsvFormat;
              exports.tsvFormatBody = tsvFormatBody;
              exports.tsvFormatRow = tsvFormatRow;
              exports.tsvFormatRows = tsvFormatRows;
              exports.tsvFormatValue = tsvFormatValue;
              exports.tsvParse = tsvParse;
              exports.tsvParseRows = tsvParseRows;
              exports.utcDay = utcDay;
              exports.utcDays = utcDays;
              exports.utcFriday = utcFriday;
              exports.utcFridays = utcFridays;
              exports.utcHour = utcHour;
              exports.utcHours = utcHours;
              exports.utcMillisecond = millisecond;
              exports.utcMilliseconds = milliseconds;
              exports.utcMinute = utcMinute;
              exports.utcMinutes = utcMinutes;
              exports.utcMonday = utcMonday;
              exports.utcMondays = utcMondays;
              exports.utcMonth = utcMonth;
              exports.utcMonths = utcMonths;
              exports.utcSaturday = utcSaturday;
              exports.utcSaturdays = utcSaturdays;
              exports.utcSecond = second;
              exports.utcSeconds = seconds;
              exports.utcSunday = utcSunday;
              exports.utcSundays = utcSundays;
              exports.utcThursday = utcThursday;
              exports.utcThursdays = utcThursdays;
              exports.utcTuesday = utcTuesday;
              exports.utcTuesdays = utcTuesdays;
              exports.utcWednesday = utcWednesday;
              exports.utcWednesdays = utcWednesdays;
              exports.utcWeek = utcSunday;
              exports.utcWeeks = utcSundays;
              exports.utcYear = utcYear;
              exports.utcYears = utcYears;
              exports.values = values;
              exports.variance = variance;
              exports.version = version;
              exports.voronoi = voronoi;
              exports.window = defaultView;
              exports.xml = xml;
              exports.zip = zip;
              exports.zoom = zoom;
              exports.zoomIdentity = identity$9;
              exports.zoomTransform = transform$1;
  
              Object.defineProperty(exports, '__esModule', {value: true});
  
          }));
  