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Use discrete colorbars for contours and polygons

See original GitHub issue

If I take the simple contour example from the docs and add a filled=True option, the %%opts seem to have no effect. I can no longer change the cmap or add a colorbar:

%%opts Contours [show_legend=False colorbar=True width=325] (cmap='fire')
x,y = np.mgrid[-50:51, -50:51] * 0.05
img = hv.Image(np.sin(x**2+y**3))
z0, z1 = img.range('z')
hv.operation.contours(img, levels=np.linspace(z0, z1, 5), overlaid=False, filled=True)

Holoviews version is 1.8.3-x-ga66181c36 via conda-forge.

Possibly related to #1558

Issue Analytics

State:
Created 6 years ago
Comments:6 (5 by maintainers)

Top GitHub Comments

3reactions

philippjfrcommented, Mar 29, 2018

We now support a color_levels argument for discrete color mapping.

1reaction

rabernatcommented, Sep 15, 2017

Great work!

My only comment would be that, with contour plots with discrete levels, we like to see discrete colorbars. This helps to read the precise values from the plot.

In matplotlib it looks like this: contours

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