ValueError: shape mismatch: objects cannot be broadcast to a single shape when plotting a bar

Question

我试着画了条形图。

purchase_value

	Buy_Coffee	Buy_ColdDrinks	Buy_Pastries	Buy_Sandwiches
0	0	1	1	0
1	1	0	0	0
2	1	0	0	1
3	1	0	0	0
4	1	0	0	1
5	1	0	0	0

plt.bar(purchase_value.index,
    purchase_value.value_counts(), 
    width=0.5, 
    bottom=None, 
    align='center', 
    color=['lightsteelblue', 
           'cornflowerblue', 
           'royalblue', 
           'midnightblue', 
           'darkblue'])
plt.xticks(rotation='vertical')
plt.show()

但是结果

ValueError: shape mismatch: objects cannot be broadcast to a single shape

Answer 1

当您调用 pandas.DataFrame.value_counts 时，您正在计算行值的每个唯一组合的计数。
因此，通过将其应用于您提供的数据，您将获得：

Buy_Coffee  Buy_ColdDrinks  Buy_Juices  Buy_Pastries  Buy_Sandwiches
1           0               0           0             0                 3
                                                      1                 2
0           1               0           1             0                 1

组合的数量可能不等于数据中的行数 (purchase_value.index)。
如果我理解正确你想绘制什么，你应该使用：

import pandas as pd
import matplotlib.pyplot as plt

purchase_value = pd.read_csv(r'data/data.csv')

fig, ax = plt.subplots()

purchase_value.plot(kind = 'bar',
                    ax = ax,
                    stacked = True, 
                    width=0.5, 
                    bottom=0, 
                    align='center', 
                    color=['lightsteelblue', 
                           'cornflowerblue', 
                           'royalblue', 
                           'midnightblue', 
                           'darkblue'])

plt.show()

如果要为每列绘制每个项目的总和，您应该使用：

fig, ax = plt.subplots()

purchase_value.sum(axis = 0).plot(kind = 'bar',
                                  ax = ax,
                                  stacked = True, 
                                  width=0.5, 
                                  bottom=0, 
                                  align='center', 
                                  color=['lightsteelblue', 
                                         'cornflowerblue', 
                                         'royalblue', 
                                         'midnightblue', 
                                         'darkblue'])

plt.tight_layout()

plt.show()

ValueError: shape mismatch: objects cannot be broadcast to a single shape when plotting a bar

ValueError: shape mismatch: objects cannot be broadcast to a single shape when plotting a bar

python

data-visualization

matplotlib

dataframe

pandas