旋转x-ticks matplotlib

Question

I can't seem to get the labels on the x-axis to rotate 90 degrees.

Example df:

import pandas as pd
import matplotlib.pyplot as plt

d = ({
    'A' : ['1','1','2','2','3','3','3'],     
    'B' : ['A','B','C','C','D','B','C'],
    'C' : ['Foo','Bar','Foo','Bar','Cat','Bar','Cat'],            
    })

df = pd.DataFrame(data=d)

fig,ax = plt.subplots(figsize = (9,4))

df.assign(A=df.A.astype(int)).pivot_table(index="C", columns="B", values="A",aggfunc='count').rename_axis(None).rename_axis(None,1).plot(kind='bar')

plt.show()

I have tried the basic:

plt.xticks(rotation = 90)

Also tried this but it returns an Attribute Error:

df.assign(A=df.A.astype(int)).pivot_table(index="C", columns="B", values="A",aggfunc='count').rename_axis(None).rename_axis(None,1).plot(kind='bar', rotation = 90)

I have got the labels to rotate through this:

xticklabels = df.C.unique()
ax.set_xticklabels(xticklabels, rotation = 0)

But it returns incorrect ordering. It just takes the values as they appear. Rather than determining the appropriate label

Answer 1

You can control the xticks labels through creating a subplot and configuring the label settings, like this:

import pandas as pd
import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(1, 1, 1)

d = ({
    'A' : ['1','1','2','2','3','3','3'],     
    'B' : ['A','B','C','C','D','B','C'],
    'C' : ['Foo','Bar','Foo','Bar','Cat','Bar','Cat'],            
    })
df = pd.DataFrame(data=d)

udf = (df.assign(A=df.A.astype(int))
 .pivot_table(index="C", columns="B", values="A",aggfunc='count')
 .rename_axis(None)
 .rename_axis(None,1))

udf.plot(kind='bar', ax=ax)

labels = ax.set_xticklabels(udf.index.values, rotation=0, fontsize=14)

The output would be:

One more thing, I think you need 0 degree rotation as the default is 90.

PS: Long chaining in pandas operations really eats away the readability.

Answer 2

I run the code below to produce the labels with angle 0. I don't understand why there are two plots generated so I deleted the line fig,ax = plt.subplots()

import pandas as pd
import matplotlib.pyplot as plt

d = ({
     'A' : ['1','1','2','2','3','3','3'],     
     'B' : ['A','B','C','C','D','B','C'],
     'C' : ['Foo','Bar','Foo','Bar','Cat','Bar','Cat'],            
     })

df = pd.DataFrame(data=d)

#fig,ax = plt.subplots()

df.assign(A=df.A.astype(int)).pivot_table(index="C", columns="B", 
values="A",aggfunc='count').rename_axis(None).rename_axis(None,1).plot(kind='bar')
plt.xticks(rotation = 0)

plt.show()