Matplotlib Xticks混淆

Question

我想使用matplotlib为两个目标组创建一个条形图:销售'1‘，而不是销售'0’。我的数据：

Sale     item                 Count
0        1.0                   3520
         2.0                      9
         3.0                   2095
         4.0                    586
         5.0                    609
         6.0                    427
         7.0                    101
         8.0                    111
1        1.0                     88
         3.0                     43
         4.0                     28
         5.0                     36
         6.0                     16
         7.0                      3
         8.0                      4

当前代码：

fig, ax = plt.subplots(figsize=(10,4))
labels=['1.0','2.0','3.0','4.0', '5.0', '6.0', '7.0', '8.0']
itemSale0 = X_train[X_train.hasSale==0]
itemSale0=itemSale0.groupby('item').size().values
x = np.arange(len(labels))  # the label locations
width = 0.35  # the width of the bars
rects1=ax.bar(x - width/2, itemSale0, width, label='Not Sale')

labels=['1.0','3.0','4.0', '5.0', '6.0', '7.0', '8.0']
itemSale1 = X_train[X_train.hasSale==1]
itemSale1 = itemSale1.groupby('item').size().values    
x = np.arange(len(labels))  # the label locations
width = 0.35  # the width of the bars
rects2=ax.bar(x + width/2, itemSale1, width, label='Sale')

# Add some text for labels, title and custom x-axis tick labels, etc.
ax.set_ylabel('Count')
ax.set_title('Sale by Traffice Source')
ax.set_xticks(x)
ax.set_xticklabels(labels)
ax.legend()

def autolabel(rects):
    """Attach a text label above each bar in *rects*, displaying its height."""
    for rect in rects:
        height = rect.get_height()
        ax.annotate('{}'.format(height),
                    xy=(rect.get_x() + rect.get_width() / 2, height),
                    xytext=(0, 3),  # 3 points vertical offset
                    textcoords="offset points",
                    ha='center', va='bottom')


autolabel(rects1)
autolabel(rects2)

问题:在图形xticks中，销售量为'0‘的项目为1.0,2.0,3.0,4.0,5.0,6.0,7.0,8.0与销售量为'1’的项目编号1.0,3.0,4.0，5.0,6.0,7.0,8.0不匹配。

items where sale is not are 1.0,2.0,3.0,4.0,5.0,6.0,7.0,8.0 
items where sale are        1.0,   ,3.0,4.0,5.0,6.0,7.0,8.0

两者是重叠的，请看附件屏幕，它不能区分第2.0项，其中9项未售出，其条形已合并到xticks第3项，其中43项已售出，我如何显示xticks，它可以将第2.0项的第9项和第3.0项的第43项分开

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Answer 1

这种柱状图很容易用Seaborn绘制。hue关键字根据给定列分配颜色，并创建“隐藏”条。

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

def autolabel(rects):
    """Attach a text label above each bar in *rects*, displaying its height."""
    for rect in rects:
        height = rect.get_height()
        ax.annotate(f'{height:.0f}',
                    xy=(rect.get_x() + rect.get_width() / 2, height),
                    xytext=(0, 3),  # 3 points vertical offset
                    textcoords="offset points",
                    ha='center', va='bottom')

df = pd.DataFrame({'Sale': [0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1],
                   'item': [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 1.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0],
                   'Count': [3520, 9, 2095, 586, 609, 427, 101, 111, 88, 43, 28, 36, 16, 3, 4]})

ax = sns.barplot(x='item', y='Count', hue='Sale', data=df)
ax.set_ylabel('Count')
ax.set_title('Sale by Traffice Source')
autolabel(ax.containers[0])
autolabel(ax.containers[1])
handles, labels = ax.get_legend_handles_labels()
ax.legend(handles, ['No sale', 'Sale'])
plt.show()

​

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PS:默认图例将“销售”(hue='Sale')列的值放入图例中。当前为0和1。要自动在图例中包含所需的字符串，可以将列值重命名为：df['Sale'] = np.where(df['Sale'] == 0, 'No sale', 'Sale')。