如何为多个组绘制带注释的堆叠栏

Question

在柱状图中，两条之间出现一个空白。有人知道为什么吗？

我知道这个错误：

FixedLocator位置(11)的数目(通常是从对set_ticks的调用)不匹配滴答标签(10)的数目。

csv文件只有2列，一列是国家名称，另一列是所取得的奖牌类型，每一行都有它的类型和国家。

指向该文件的链接是：https://github.com/jpiedehierroa/files/blob/main/Libro1.csv

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

from pathlib import Path
my_csv = Path("C:/Usersjosep/Desktop/Libro1.csv")
df = pd.read_csv("Libro1.csv", sep=',')

# or load from github repo link
url = 'https://raw.githubusercontent.com/jpiedehierroa/files/main/Libro1.csv'
df = pd.read_csv(url)    

# Prepare data
x_var = 'countries'
groupby_var = 'type'
df_agg = df.loc[:,[x_var, groupby_var]].groupby(groupby_var)
vals = [df[x_var].values.tolist() for i, df in df_agg]

# Draw
plt.figure(figsize=(10,10), dpi= 100)
colors= ("#CD7F32","silver","gold")
n, bins, patches = plt.hist(vals, df[x_var].unique().__len__(), stacked=True, density=False, color=colors[:len(vals)])

# Decoration
plt.legend(["bronze", "silver","gold"], loc="upper right")
plt.title(f"Histogram of medals achieved by ${x_var}$ colored by ${groupby_var}$ in Tokyo 2020", fontsize=18)
plt.text(2,80,"138")
plt.xlabel(x_var)
plt.ylabel("amount of medals by type")
plt.ylim(0, 130)
plt.xticks(ticks=bins, labels=np.unique(df[x_var]).tolist(), rotation=90, horizontalalignment='left')
plt.show()

​

​

试验数据

• ，以防链接死

countries,type
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,gold
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,silver
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
USA,bronze
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,gold
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,silver
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
China,bronze
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,gold
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,silver
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
Japan,bronze
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,gold
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,silver
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
GB,bronze
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,gold
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,silver
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
ROC,bronze
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,gold
Australia,silver
Australia,silver
Australia,silver
Australia,silver
Australia,silver
Australia,silver
Australia,silver
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Australia,bronze
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,gold
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,silver
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
Netherlands,bronze
France,gold
France,gold
France,gold
France,gold
France,gold
France,gold
France,gold
France,gold
France,gold
France,gold
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,silver
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
France,bronze
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,gold
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,silver
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Germany,bronze
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,gold
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,silver
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze
Italy,bronze

Answer 1

这更容易实现为一个堆叠的条形图，因此，用pandas.crosstab重塑数据图，用pandas.DataFrame.plot和kind='bar'和stacked=True

• 来实现图--这不应该用plt.hist实现，因为它更复杂，而且更容易使用熊猫绘图方法--当x值是一个连续的数字范围，而不是离散的分类values.

时，使用直方图更合适。

• ct.iloc[:, :-1]选择除最后一列以外的所有列( 'tot'将被绘制为条形图)。
• 使用matplotlib.pyplot.bar_label添加注释(默认情况下使用label_type='edge' )，这将导致用累积和注释边缘('center'用修补程序值注释)，如此answer所示。
  • ax.containers[2]中的[2]只选择要用累积和注释的顶级容器。将bottom.

中的containers索引为0

- See this [answer](https://stackoverflow.com/a/67561982/7758804) for additional details and examples
- This [answer](https://stackoverflow.com/a/64202669/7758804) shows how to do annotations the old way, without `.bar_label`. I do not recommend it.
- This [answer](https://stackoverflow.com/a/68785457/7758804) shows how to customize labels to prevent annotations for values under a given size.

• Tested in python 3.10**，** pandas 1.3.5**，** matplotlib 3.5.1

加载和形状DataFrame

import pandas as pd

# load from github repo link
url = 'https://raw.githubusercontent.com/jpiedehierroa/files/main/Libro1.csv'
df = pd.read_csv(url) 

# reshape the dataframe
ct = pd.crosstab(df.countries, df.type)

# total medals per country, which is necessary to sort the bars
ct['tot'] = ct.sum(axis=1)

# sort
ct = ct.sort_values(by='tot', ascending=False)

# display(ct)
type         bronze  gold  silver  tot
countries                             
USA              33    39      41  113
China            18    38      32   88
ROC              23    20      28   71
GB               22    22      21   65
Japan            17    27      14   58
Australia        22    17       7   46
Italy            20    10      10   40
Germany          16    10      11   37
Netherlands      14    10      12   36
France           11    10      12   33

绘图

colors = ("#CD7F32", "silver", "gold")
cd = dict(zip(ct.columns, colors))

# plot the medals columns
title = 'Country Medal Count for Tokyo 2020'
ax = ct.iloc[:, :-1].plot(kind='bar', stacked=True, color=cd, title=title,
                          figsize=(12, 5), rot=0, width=1, ec='k' )

# annotate each container with individual values
for c in ax.containers:
    ax.bar_label(c, label_type='center')
    
# annotate the top containers with the cumulative sum
ax.bar_label(ax.containers[2], padding=3)

# pad the spacing between the number and the edge of the figure
ax.margins(y=0.1)

​

​

• 用和注释顶部的另一种方法是将'tot'列用于自定义标签，但如图所示，这是不必要的。

labels = ct.tot.tolist()
ax.bar_label(ax.containers[2], labels=labels, padding=3)