如何在python中为不同的条形图组赋予不同的颜色？

Question

我正在尝试绘制一组条形图。我可以在每个组中赋予不同的颜色，但是如何为不同的组赋予不同的颜色？

MWE

import numpy as np
import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt



df = pd.DataFrame({0: [10,20,80],
                  1: [20,40,60]},index=['a','b','c'])

df

# another test dataframe
df = pd.DataFrame({0: [10,20,80,10],
                  1: [20,40,60,70],
                  2: [20,40,60,70],
                  },
                  index=['a','b','c','d'])

pal = 'magma'
color=sns.color_palette(pal,len(df)) # list of rgb

fig, ax = plt.subplots()

df.plot.bar(ax=ax,color=color)

输出

必填

这里的变量color 有三个值，我想用这三种颜色代表三个组。例如组a 现在有两种颜色，我希望它只有一种颜色。

类似链接

• python assign different colors to bars in barplot

Answer 1

这是使用plt.bar()的解决方法

import numpy as np
import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt



df = pd.DataFrame({0: [10,20,80],
                  1: [20,40,60],
                  'g':['a','b','c']})

pal = 'magma'
color=sns.color_palette(pal,len(df)) # list of rgb

fig, ax = plt.subplots()


width=.25

gb = df.groupby('g')
positions = range(len(gb))

for c, x, (_, group) in zip(color, positions, gb):

    ax.bar(x-width/2, group[0], width, color=c, edgecolor='k')
    ax.bar(x+width/2, group[1], width, color=c, edgecolor='k')

ax.set_xticks(positions)
ax.set_xticklabels(df['g'])      

Answer 2

你可以使用axis.patches：

import numpy as np
import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt


df = pd.DataFrame({0: [10,20,80,10],
                  1: [20,40,60,70],
                  2: [20,40,60,70],
                  },
                  index=['a','b','c','d'])

pal = 'magma'
color = sns.color_palette(pal,len(df)) # list of rgb
color = color * df.shape[1]


fig, ax = plt.subplots()

df.plot.bar(ax=ax)
ax.get_legend().remove()

for p,c in zip(ax.patches,color):
    p.set_color(c)

提供：