text: d3.tip=function(){var direction=d3_tip_direction,offset=d3_tip_offset,html=d3_tip_html,node=initNode(),svg=null,point=null,target=null;function tip(vis){svg=getSVGNode(vis);point=svg.createSVGPoint();document.body.appendChild(node)}tip.show=function(){var args=Array.prototype.slice.call(arguments);if(args[args.length-1]instanceof SVGElement)target=args.pop();var content=html.apply(this,args),poffset=offset.apply(this,args),dir=direction.apply(this,args),nodel=d3.select(node),i=0,coords;nodel.html(content).style({opacity:1,"pointer-events":"all"});while(i--)nodel.classed(directions[i],false);coords=direction_callbacks.get(dir).apply(this);nodel.classed(dir,true).style({top:coords.top+poffset[0]+"px",left:coords.left+poffset[1]+"px"});return tip};tip.hide=function(){nodel=d3.select(node);nodel.style({opacity:0,"pointer-events":"none"});return tip};tip.attr=function(n,v){if(arguments.length<2&&typeof n==="string"){return d3.select(node).attr(n)}else{var args=Array.prototype.slice.call(arguments);d3.selection.prototype.attr.apply(d3.select(node),args)}return tip};tip.style=function(n,v){if(arguments.length<2&&typeof n==="string"){return d3.select(node).style(n)}else{var args=Array.prototype.slice.call(arguments);d3.selection.prototype.style.apply(d3.select(node),args)}return tip};tip.direction=function(v){if(!arguments.length)return direction;direction=v==null?v:d3.functor(v);return tip};tip.offset=function(v){if(!arguments.length)return offset;offset=v==null?v:d3.functor(v);return tip};tip.html=function(v){if(!arguments.length)return html;html=v==null?v:d3.functor(v);return tip};function d3_tip_direction(){return"n"}function d3_tip_offset(){return[0,0]}function d3_tip_html(){return" "}var direction_callbacks=d3.map({n:direction_n,s:direction_s,e:direction_e,w:direction_w,nw:direction_nw,ne:direction_ne,sw:direction_sw,se:direction_se}),directions=direction_callbacks.keys();function direction_n(){var bbox=getScreenBBox();return{top:bbox.n.y-node.offsetHeight,left:bbox.n.x-node.offsetWidth/2}}function direction_s(){var bbox=getScreenBBox();return{top:bbox.s.y,left:bbox.s.x-node.offsetWidth/2}}function direction_e(){var bbox=getScreenBBox();return{top:bbox.e.y-node.offsetHeight/2,left:bbox.e.x}}function direction_w(){var bbox=getScreenBBox();return{top:bbox.w.y-node.offsetHeight/2,left:bbox.w.x-node.offsetWidth}}function direction_nw(){var bbox=getScreenBBox();return{top:bbox.nw.y-node.offsetHeight,left:bbox.nw.x-node.offsetWidth}}function direction_ne(){var bbox=getScreenBBox();return{top:bbox.ne.y-node.offsetHeight,left:bbox.ne.x}}function direction_sw(){var bbox=getScreenBBox();return{top:bbox.sw.y,left:bbox.sw.x-node.offsetWidth}}function direction_se(){var bbox=getScreenBBox();return{top:bbox.se.y,left:bbox.e.x}}function initNode(){var node=d3.select(document.createElement("div"));node.style({position:"absolute",opacity:0,pointerEvents:"none",boxSizing:"border-box"});return node.node()}function getSVGNode(el){el=el.node();if(el.tagName.toLowerCase()=="svg")return el;return el.ownerSVGElement}function getScreenBBox(){var targetel=target||d3.event.target,bbox={},matrix=targetel.getScreenCTM(),tbbox=targetel.getBBox(),width=tbbox.width,height=tbbox.height,x=tbbox.x,y=tbbox.y,scrollTop=document.documentElement.scrollTop||document.body.scrollTop,scrollLeft=document.documentElement.scrollLeft||document.body.scrollLeft;point.x=x+scrollLeft;point.y=y+scrollTop;bbox.nw=point.matrixTransform(matrix);point.x+=width;bbox.ne=point.matrixTransform(matrix);point.y+=height;bbox.se=point.matrixTransform(matrix);point.x-=width;bbox.sw=point.matrixTransform(matrix);point.y-=height/2;bbox.w=point.matrixTransform(matrix);point.x+=width;bbox.e=point.matrixTransform(matrix);point.x-=width/2;point.y-=height/2;bbox.n=point.matrixTransform(matrix);point.y+=height;bbox.s=point.matrixTransform(matrix);return bbox}return tip};
  