Unsure if it is possible to leverage matplotlib’s DivergingNorm for color maps under the framework of pandas Styler objects. As an example:
import pandas as pd import matplotlib.cm # retrieve red-yellow-green diverging color map cmap = matplotlib.cm.get_cmap('RdYlGn') # create sample pd.DataFrame ix = pd.date_range(start=pd.Timestamp(2020, 1, 1), periods=4) df = pd.DataFrame(index=ix, columns=['D/D CHANGE'], data=[-1, 0, 2, 5]) df.style.background_gradient(cmap=cmap)
Ideally only negative (positive) values would appear red (green).
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Answer
It doesn’t look like there is an option to pass a custom normalization to background_gradient
(maybe could be a feature request to post on pandas github). But you can use a custom function to get the desired result:
def background_with_norm(s): cmap = matplotlib.cm.get_cmap('RdYlGn') norm = matplotlib.colors.DivergingNorm(vmin=s.values.min(), vcenter=0, vmax=s.values.max()) return ['background-color: {:s}'.format(matplotlib.colors.to_hex(c.flatten())) for c in cmap(norm(s.values))] # create sample pd.DataFrame ix = pd.date_range(start=pd.Timestamp(2020, 1, 1), periods=4) df = pd.DataFrame(index=ix, columns=['D/D CHANGE'], data=[-1, 0, 2, 5]) df.style.apply(background_with_norm)