text: """Bokeh Plot posterior densities."""
  from numbers import Number
  from typing import Optional
  
  import bokeh.plotting as bkp
  import numpy as np
  from bokeh.layouts import gridplot
  from bokeh.models.annotations import Title
  
  from . import backend_kwarg_defaults, backend_show
  from ...kdeplot import plot_kde
  from ...plot_utils import (
      make_label,
      _create_axes_grid,
      format_sig_figs,
      round_num,
      calculate_point_estimate,
      get_bins,
  )
  from ....stats import hpd
  
  
  def plot_posterior(
      ax,
      length_plotters,
      rows,
      cols,
      figsize,
      plotters,
      bw,
      bins,
      kind,
      point_estimate,
      round_to,
      credible_interval,
      multimodal,
      ref_val,
      rope,
      ax_labelsize,
      kwargs,
      backend_kwargs,
      show,
  ):
      """Bokeh posterior plot."""
      if backend_kwargs is None:
          backend_kwargs = {}
  
      backend_kwargs = {
          **backend_kwarg_defaults(),
          **backend_kwargs,
      }
      if ax is None:
          _, ax = _create_axes_grid(
              length_plotters,
              rows,
              cols,
              figsize=figsize,
              squeeze=False,
              backend="bokeh",
              backend_kwargs=backend_kwargs,
          )
      else:
          ax = np.atleast_2d(ax)
      idx = 0
      for (var_name, selection, x), ax_ in zip(
          plotters, (item for item in ax.flatten() if item is not None)
      ):
          _plot_posterior_op(
              idx,
              x.flatten(),
              var_name,
              selection,
              ax=ax_,
              bw=bw,
              bins=bins,
              kind=kind,
              point_estimate=point_estimate,
              round_to=round_to,
              credible_interval=credible_interval,
              multimodal=multimodal,
              ref_val=ref_val,
              rope=rope,
              ax_labelsize=ax_labelsize,
              **kwargs
          )
          idx += 1
          _title = Title()
          _title.text = make_label(var_name, selection)
          ax_.title = _title
  
      if backend_show(show):
          grid = gridplot(ax.tolist(), toolbar_location="above")
          bkp.show(grid)
  
      return ax
  
  
  def _plot_posterior_op(
      idx,
      values,
      var_name,
      selection,
      ax,
      bw,
      linewidth,
      bins,
      kind,
      point_estimate,
      credible_interval,
      multimodal,
      ref_val,
      rope,
      ax_labelsize,
      round_to: Optional[int] = None,
      **kwargs
  ):  # noqa: D202
      """Artist to draw posterior."""
  
      def format_as_percent(x, round_to=0):
          return "{0:.{1:d}f}%".format(100 * x, round_to)
  
      def display_ref_val(max_data):
          if ref_val is None:
              return
          elif isinstance(ref_val, dict):
              val = None
              for sel in ref_val.get(var_name, []):
                  if all(
                      k in selection and selection[k] == v for k, v in sel.items() if k != "ref_val"
                  ):
                      val = sel["ref_val"]
                      break
              if val is None:
                  return
          elif isinstance(ref_val, list):
              val = ref_val[idx]
          elif isinstance(ref_val, Number):
              val = ref_val
          else:
              raise ValueError(
                  "Argument `ref_val` must be None, a constant, a list or a "
                  'dictionary like {"var_name": [{"ref_val": ref_val}]}'
              )
          less_than_ref_probability = (values < val).mean()
          greater_than_ref_probability = (values >= val).mean()
          ref_in_posterior = "{} <{:g}< {}".format(
              format_as_percent(less_than_ref_probability, 1),
              val,
              format_as_percent(greater_than_ref_probability, 1),
          )
          ax.line([val, val], [0, 0.8 * max_data], line_color="blue", line_alpha=0.65)
  
          ax.text(x=[values.mean()], y=[max_data * 0.6], text=[ref_in_posterior], text_align="center")
  
      def display_rope(max_data):
          if rope is None:
              return
          elif isinstance(rope, dict):
              vals = None
              for sel in rope.get(var_name, []):
                  # pylint: disable=line-too-long
                  if all(k in selection and selection[k] == v for k, v in sel.items() if k != "rope"):
                      vals = sel["rope"]
                      break
              if vals is None:
                  return
          elif len(rope) == 2:
              vals = rope
          else:
              raise ValueError(
                  "Argument `rope` must be None, a dictionary like"
                  '{"var_name": {"rope": (lo, hi)}}, or an'
                  "iterable of length 2"
              )
  
          ax.line(
              vals,
              (max_data * 0.02, max_data * 0.02),
              line_width=linewidth * 5,
              line_color="red",
              line_alpha=0.7,
          )
  
          text_props = dict(
              text_font_size="{}pt".format(ax_labelsize), text_color="black", text_align="center"
          )
  
          ax.text(x=vals, y=[max_data * 0.2, max_data * 0.2], text=list(map(str, vals)), **text_props)
  
      def display_point_estimate(max_data):
          if not point_estimate:
              return
          point_value = calculate_point_estimate(point_estimate, values, bw)
          sig_figs = format_sig_figs(point_value, round_to)
          point_text = "{point_estimate}={point_value:.{sig_figs}g}".format(
              point_estimate=point_estimate, point_value=point_value, sig_figs=sig_figs
          )
  
          ax.text(x=[point_value], y=[max_data * 0.8], text=[point_text], text_align="center")
  
      def display_hpd(max_data):
          # np.ndarray with 2 entries, min and max
          # pylint: disable=line-too-long
          hpd_intervals = hpd(
              values, credible_interval=credible_interval, multimodal=multimodal
          )  # type: np.ndarray
  
          for hpdi in np.atleast_2d(hpd_intervals):
              ax.line(
                  hpdi,
                  (max_data * 0.02, max_data * 0.02),
                  line_width=linewidth * 2,
                  line_color="black",
              )
  
              ax.text(
                  x=list(hpdi) + [(hpdi[0] + hpdi[1]) / 2],
                  y=[max_data * 0.07, max_data * 0.07, max_data * 0.3],
                  text=list(map(str, map(lambda x: round_num(x, round_to), hpdi)))
                  + [format_as_percent(credible_interval) + " HPD"],
                  text_align="center",
              )
  
      def format_axes():
          ax.yaxis.visible = False
          ax.yaxis.major_tick_line_color = None
          ax.yaxis.minor_tick_line_color = None
          ax.yaxis.major_label_text_font_size = "0pt"
          ax.xgrid.grid_line_color = None
          ax.ygrid.grid_line_color = None
  
      if kind == "kde" and values.dtype.kind == "f":
          kwargs.setdefault("line_width", linewidth)
          plot_kde(
              values,
              bw=bw,
              fill_kwargs={"fill_alpha": kwargs.pop("fill_alpha", 0)},
              plot_kwargs=kwargs,
              ax=ax,
              rug=False,
              backend="bokeh",
              backend_kwargs={},
              show=False,
          )
          hist, edges = np.histogram(values, density=True)
      else:
          if bins is None:
              if values.dtype.kind == "i":
                  bins = get_bins(values)
              else:
                  bins = "auto"
          kwargs.setdefault("align", "left")
          kwargs.setdefault("color", "blue")
          hist, edges = np.histogram(values, density=True, bins=bins)
          ax.quad(
              top=hist, bottom=0, left=edges[:-1], right=edges[1:], fill_alpha=0.35, line_alpha=0.35
          )
  
      format_axes()
      max_data = hist.max()
      if credible_interval is not None:
          display_hpd(max_data)
      display_point_estimate(max_data)
      display_ref_val(max_data)
      display_rope(max_data)
  