python - On my horizontal bar plot how do I assign specific color to certain index

Question

this is my simplified code

import numpy as np
import pandas as pd
pd.DataFrame(np.random.randint(1,100,6),index=['1200 am', '1230 am', '0340 pm', '1200 pm', '1030 am', '0140 pm'],columns=['value']).plot(kind='barh')

I want bars for "am" colored in red to distinguish between "am" and "pm", how do I do that?

Does this answer your question? [Setting Different Bar color in matplotlib Python](https://stackoverflow.com/questions/18973404/setting-different-bar-color-in-matplotlib-python) — BigBen, Feb 11 '22 at 16:40

Stef · Accepted Answer · 2022-02-20T16:05:25.733

0

You can plot your data in two passes using a mask like so:

import numpy as np
import pandas as pd
df = pd.DataFrame(np.random.randint(1,100,6), 
             index=['1200 am', '1230 am', '0340 pm', '1200 pm', '1030 am', '0140 pm'],
             columns=['value'])

m = df.index.str.contains('am')
ax = df.value.mask(m).plot(kind='barh', label='pm', legend=True)
df.value.mask(~m).plot(kind='barh', color='r', ax=ax, label='am', legend=True)

edited Feb 20 '22 at 16:05

answered Feb 11 '22 at 16:54

Stef

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just one more Q, is there a quick way to add legend to show red is "am" and blue is 'pm'? – user13412850 Feb 12 '22 at 12:30
@user13412850: sure, see the updated answer using the `label` and `legend` arguments. – Stef Feb 20 '22 at 16:06

python - On my horizontal bar plot how do I assign specific color to certain index

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