如何在散景图像图中更改颜色映射器

Question

I have a Bokeh image plot that I want to change interactively, eg:

color_mapper = LinearColorMapper(palette="Viridis256", low=tmp.min(), high=tmp.max())
p = figure(plot_width=tmp.shape[0], plot_height=tmp.shape[1], 
           x_range=(0, tmp.shape[0]), y_range=(0, tmp.shape[1]))
img = p.image(image=[tmp], x=[0], y=[0], dw=[tmp.shape[0]], 
              dh=[tmp.shape[1]], color_mapper=color_mapper)

I can update the range in the colour map by using:

cm = p.select_one(LinearColorMapper)
cm.update(low=new_data.min(), high=new_data.max())
push_notebook()

However, I would like to interactively be able to change to a different type of colour map, eg from LinearColorMapper to LogColorMapper . The above only lets me access the LinearColorMapper object, not replace it. Is there a way to do this interactively without having to call image again?

Answer 1

Found it, this is in the glyph object of the image instance. One can just replace it with another ColorMapper , eg:

img.glyph.color_mapper = LogColorMapper(palette="Viridis256",
                                        low=new_data.min(),
                                        high=new_data.max())
push_notebook()