如何使用 matplotlib 将标签放在两个图表中

Question

我正在尝试使用分组依据的结果绘制两个直方图。但是标签只出现在其中一个标签中。如何将标签放在两个图表中？以及如何为图表设置不同的标题（例如首先作为男性等级，其次作为女性等级）

import pandas as pd
import matplotlib.pyplot as plt

microdataEnem = pd.read_csv('C:\Users\Lucas\AppData\Local\Programs\Python\Python39\Scripts\Data Science\Data Analysis\Projects\ENEM\DADOS\MICRODADOS_ENEM_2019.csv', sep = ';', encoding = 'ISO-8859-1', nrows=10000)

sex_essaygrade = ['TP_SEXO', 'NU_NOTA_REDACAO']

filter_sex_essaygrade = microdataEnem.filter(items = sex_essaygrade)

filter_sex_essaygrade.dropna(subset = ['NU_NOTA_REDACAO'], inplace = True)
       
filter_sex_essaygrade.groupby('TP_SEXO').hist()
plt.xlabel('Grade')
plt.ylabel('Number of students')


plt.show()

Answer 1

您可以尝试使用以下格式来代替 filter_sex_essaygrade.groupby('TP_SEXO').hist()：axs = filter_sex_essaygrade['NU_NOTA_REDACAO'].hist(by=filter_sex_essaygrade['TP_SEXO'])。这将自动使用组名称为每个直方图命名。

您需要将变量 axs 设置为等于此直方图对象，以便您可以修改两个图的 x 和 y 标签。

我创建了一些与您类似的数据，得到以下结果：

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

np.random.seed(42)

sex_essaygrade = ['TP_SEXO', 'NU_NOTA_REDACAO']

## create two distinct sets of grades
sample_grades = np.concatenate((np.random.randint(low=70,high=100,size=100), np.random.randint(low=80,high=100,size=100)))

filter_sex_essaygrade = pd.DataFrame({
    'NU_NOTA_REDACAO': sample_grades,
    'TP_SEXO': ['Men']*100 + ['Women']*100
})
       
axs = filter_sex_essaygrade['NU_NOTA_REDACAO'].hist(by=filter_sex_essaygrade['TP_SEXO'])
for ax in axs.flatten():
    ax.set_xlabel("Grade")
    ax.set_ylabel("Number of students")

plt.show()

如何使用 matplotlib 将标签放在两个图表中

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