code: def test_heatmap_alpha_dim(self):
      data = {
          "row": [1, 2, 1, 2],
          "col": [1, 2, 2, 1],
          "alpha": [0, 0, 0, 1],
          "val": [0.5, 0.6, 0.2, 0.1],
      }
      hm = HeatMap(
          data, kdims=["col", "row"], vdims=["val", "alpha"]
      ).opts(alpha="alpha")
      plot = bokeh_renderer.get_plot(hm)
      cds = plot.handles["cds"]
      self.assertEqual(cds.data["row"], np.array([1, 2, 1, 2]))
      self.assertEqual(cds.data["col"], np.array([1, 1, 2, 2]))
      self.assertEqual(cds.data["alpha"], np.array([0, 1, 0, 0]))
      self.assertEqual(
          cds.data["zvalues"], np.array([0.5, 0.1, 0.2, 0.6])
      )
  
file_path: holoviews/holoviews/tests/plotting/bokeh/test_heatmapplot.py
imports: import numpy
  from bokeh.models import FactorRange, HoverTool, Range1d
  from holoviews.element import HeatMap, Image, Points
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 14 for calling the TestHeatMapPlot obj's underlying member method code with example usage: obj.test_heatmap_alpha_dim() without return types