Python：在单个图中绘制多列

Question

df contains multiple columns and the three columns I need to plot are

gen_1    gen_2    gen_3

M          M        M
F          M        M
F          F        F
F          F        M
F          M        F

To plot them in different graph

df.groupby('gen_1')['pid'].nunique().plot(kind='bar')
plt.show()
df.groupby('gen_2')['pid'].nunique().plot(kind='bar')
plt.show()
df.groupby('gen_3')['pid'].nunique().plot(kind='bar')
plt.show()

But I need them in a single graph to compare.

Answer 1

I never use the pandas plotting tools. Plotting from pandas works fine, I just prefer to stick to my routine. I create figures manually, so this is one option. Here is an example:

import pylab as pl

fig = pl.figure(figsize=(3.25, 2.5))
ax0 = fig.add_subplot(111)

ax0.bar(df.index, df.groupby('gen_1')['pid'].nunique())
ax0.bar(df.index, df.groupby('gen_2')['pid'].nunique())
ax0.bar(df.index, df.groupby('gen_3')['pid'].nunique())

fig.show()

pl.savefig("filename.png", bbox_inches="tight", dpi=500)
pl.close("all")