如何向 matplotlib 注释添加额外的文本

How to add additional text to matplotlib annotations

我使用 seaborn 的 titanic 数据集作为我非常大的数据集的代理来创建基于它的图表和数据。

以下代码运行没有任何错误:

import seaborn as sns
import pandas as pd
import numpy as np
sns.set_theme(style="darkgrid")

# Load the example Titanic dataset
df = sns.load_dataset("titanic")

# split fare into decile groups and order them
df['fare_grp'] = pd.qcut(df['fare'], q=10,labels=None, retbins=False, precision=0).astype(str)
df.groupby(['fare_grp'],dropna=False).size()
df['fare_grp_num'] = pd.qcut(df['fare'], q=10,labels=False, retbins=False, precision=0).astype(str)
df.groupby(['fare_grp_num'],dropna=False).size()
df['fare_ord_grp'] = df['fare_grp_num'] + ' ' +df['fare_grp']
df['fare_ord_grp']

# set variables
target = 'survived'
ydim = 'fare_ord_grp'
xdim = 'embark_town'

#del [result]

non_events = pd.DataFrame(df[df[target]==0].groupby([ydim,xdim],as_index=False, dropna=False)[target].count()).rename(columns={target: 'non_events'})
non_events[xdim]=non_events[xdim].replace(np.nan, 'Missing', regex=True)
non_events[ydim]=non_events[ydim].replace(np.nan, 'Missing', regex=True)
non_events_total = pd.DataFrame(df[df[target]==0].groupby([xdim],dropna=False,as_index=False)[target].count()).rename(columns={target: 'non_events_total_by_xdim'}).replace(np.nan, 'Missing', regex=True)

events = pd.DataFrame(df[df[target]==1].groupby([ydim,xdim],as_index=False, dropna=False)[target].count()).rename(columns={target: 'events'})
events[xdim]=events[xdim].replace(np.nan, 'Missing', regex=True)
events[ydim]=events[ydim].replace(np.nan, 'Missing', regex=True)
events_total = pd.DataFrame(df[df[target]==1].groupby([xdim],dropna=False,as_index=False)[target].count()).rename(columns={target: 'events_total_by_xdim'}).replace(np.nan, 'Missing', regex=True)

grand_total = pd.DataFrame(df.groupby([xdim],dropna=False,as_index=False)[target].count()).rename(columns={target: 'total_by_xdim'}).replace(np.nan, 'Missing', regex=True)

grand_total=grand_total.merge(non_events_total, how='left', on=xdim).merge(events_total, how='left', on=xdim)

result = pd.merge(non_events, events, how="outer",on=[ydim,xdim])

result['total'] = result['non_events'].fillna(0) + result['events'].fillna(0)
result[xdim] = result[xdim].replace(np.nan, 'Missing', regex=True)
result = pd.merge(result, grand_total, how="left",on=[xdim])

result['survival rate %'] = round(result['events']/result['total']*100,2)
result['% event dist by xdim'] = round(result['events']/result['events_total_by_xdim']*100,2)
result['% non-event dist by xdim'] = round(result['non_events']/result['non_events_total_by_xdim']*100,2)
result['% total dist by xdim'] = round(result['total']/result['total_by_xdim']*100,2)

display(result)
value_name1 = "% dist by " + str(xdim)
dfl = pd.melt(result, id_vars=[ydim, xdim],value_vars =['% total dist by xdim'], var_name = 'Type',value_name=value_name1).drop(columns='Type')
dfl2 = dfl.pivot(index=ydim, columns=xdim, values=value_name1)
print(dfl2)
title1 = "% dist by " + str(xdim)
ax=dfl2.T.plot(kind='bar', stacked=True, rot=1, figsize=(8, 8), title=title1)
ax.set_xticklabels(ax.get_xticklabels(), rotation=45)
ax.legend(bbox_to_anchor=(1.0, 1.0),title = 'Fare Range')
ax.set_ylabel('% Dist')
for p in ax.patches:
    width, height = p.get_width(), p.get_height()
    x, y = p.get_xy() 
    ax.text(x+width/2, y+height/2,'{:.0f}%'.format(height),horizontalalignment='center', verticalalignment='center')

它会生成以下堆积百分比条形图,它显示了按登船城镇的总分布百分比。

我还想显示存活率以及每个块中的 % 分布。例如,对于皇后镇,票价范围 1 (7.6, 7.9),总分布百分比为 56%。我想将生存率 37.21% 显示为 (56%, 37.21%)。我无法弄清楚。请提供任何建议。谢谢。

这里是输出摘要table供参考

fare_ord_grp embark_town non_events events total total_by_xdim non_events_total_by_xdim events_total_by_xdim survival rate % % event dist by xdim % non-event dist by xdim % total dist by xdim
0 0 (-0.1,7.6] Cherbourg 22 7 29 168 75 93 24.14 7.53 29.33 17.26
1 0 (-0.1,7.6] Queenstown 4 NaN 4 77 47 30 NaN NaN 8.51 5.19
2 0 (-0.1,7.6] Southampton 53 6 59 644 427 217 10.17 2.76 12.41 9.16
3 1 (7.6,7.9] Queenstown 27 16 43 77 47 30 37.21 53.33 57.45 55.84
4 1 (7.6,7.9] Southampton 34 10 44 644 427 217 22.73 4.61 7.96 6.83
5 2 (7.9,8] Cherbourg 4 1 5 168 75 93 20 1.08 5.33 2.98
6 2 (7.9,8] Southampton 83 13 96 644 427 217 13.54 5.99 19.44 14.91
7 3 (8.0,10.5] Cherbourg 2 1 3 168 75 93 33.33 1.08 2.67 1.79
8 3 (8.0,10.5] Queenstown 2 NaN 2 77 47 30 NaN NaN 4.26 2.6
9 3 (8.0,10.5] Southampton 56 17 73 644 427 217 23.29 7.83 13.11 11.34
10 4 (10.5,14.5] Cherbourg 7 8 15 168 75 93 53.33 8.6 9.33 8.93
11 4 (10.5,14.5] Queenstown 1 2 3 77 47 30 66.67 6.67 2.13 3.9
12 4 (10.5,14.5] Southampton 40 26 66 644 427 217 39.39 11.98 9.37 10.25
13 5 (14.5,21.7] Cherbourg 9 10 19 168 75 93 52.63 10.75 12 11.31
14 5 (14.5,21.7] Queenstown 5 3 8 77 47 30 37.5 10 10.64 10.39
15 5 (14.5,21.7] Southampton 37 24 61 644 427 217 39.34 11.06 8.67 9.47
16 6 (21.7,27] Cherbourg 1 4 5 168 75 93 80 4.3 1.33 2.98
17 6 (21.7,27] Queenstown 2 3 5 77 47 30 60 10 4.26 6.49
18 6 (21.7,27] Southampton 40 39 79 644 427 217 49.37 17.97 9.37 12.27
19 7 (27.0,39.7] Cherbourg 14 10 24 168 75 93 41.67 10.75 18.67 14.29
20 7 (27.0,39.7] Queenstown 5 NaN 5 77 47 30 NaN NaN 10.64 6.49
21 7 (27.0,39.7] Southampton 38 24 62 644 427 217 38.71 11.06 8.9 9.63
22 8 (39.7,78] Cherbourg 5 19 24 168 75 93 79.17 20.43 6.67 14.29
23 8 (39.7,78] Southampton 37 28 65 644 427 217 43.08 12.9 8.67 10.09
24 9 (78.0,512.3] Cherbourg 11 33 44 168 75 93 75 35.48 14.67 26.19
25 9 (78.0,512.3] Queenstown 1 1 2 77 47 30 50 3.33 2.13 2.6
26 9 (78.0,512.3] Southampton 9 30 39 644 427 217 76.92 13.82 2.11 6.06
27 2 (7.9,8] Queenstown NaN 5 5 77 47 30 100 16.67 NaN 6.49
28 9 (78.0,512.3] Missing NaN 2 2 2 NaN 2 100 100 NaN 100
  • dfl2.T 正在绘制,但 'survival rate %'result 中。因此,来自 dfl2.T 的值的索引不对应于 'survival rate %'.
  • 因为 result['% total dist by xdim'] 中的所有值都是 不是唯一的,我们不能使用匹配的key-values.
  • dict
  • 'survival rate %'创建一个对应的pivoted DataFrame,然后将其展平。所有值的顺序与 dfl2.T 中的 '% total dist by xdim' 值的顺序相同。因此,它们可以被索引。
  • 相对于 dfl2.T,绘图 API 按列顺序绘制,这意味着必须使用 .flatten(order='F') 以正确的顺序展平数组以进行索引。
# create a corresponding pivoted dataframe for survival rate %
dfl3 = pd.melt(result, id_vars=[ydim, xdim],value_vars =['survival rate %'], var_name = 'Type',value_name=value_name1).drop(columns='Type')
dfl4 = dfl3.pivot(index=ydim, columns=xdim, values=value_name1)

# flatten dfl4.T in column order
dfl4_flattened = dfl4.T.to_numpy().flatten(order='F')

for i, p in enumerate(ax.patches):
    width, height = p.get_width(), p.get_height()
    x, y = p.get_xy() 
    
    # only print values when height is not 0
    if height != 0:
        
        # create the text string
        text = f'{height:.0f}%, {dfl4_flattened[i]:.0f}%'
        
        # annotate the bar segments
        ax.text(x+width/2, y+height/2, text, horizontalalignment='center', verticalalignment='center')

备注

  • 这里可以看到dfl2.Tdfl4.T
# dfl2.T
fare_ord_grp  0 (-0.1, 7.6]  1 (7.6, 7.9]  2 (7.9, 8.0]  3 (8.0, 10.5]  4 (10.5, 14.5]  5 (14.5, 21.7]  6 (21.7, 27.0]  7 (27.0, 39.7]  8 (39.7, 78.0]  9 (78.0, 512.3]
embark_town                                                                                                                                                            
Cherbourg             17.26           NaN          2.98           1.79            8.93           11.31            2.98           14.29           14.29            26.19
Missing                 NaN           NaN           NaN            NaN             NaN             NaN             NaN             NaN             NaN           100.00
Queenstown             5.19         55.84          6.49           2.60            3.90           10.39            6.49            6.49             NaN             2.60
Southampton            9.16          6.83         14.91          11.34           10.25            9.47           12.27            9.63           10.09             6.06

# dfl4.T
fare_ord_grp  0 (-0.1, 7.6]  1 (7.6, 7.9]  2 (7.9, 8.0]  3 (8.0, 10.5]  4 (10.5, 14.5]  5 (14.5, 21.7]  6 (21.7, 27.0]  7 (27.0, 39.7]  8 (39.7, 78.0]  9 (78.0, 512.3]
embark_town                                                                                                                                                            
Cherbourg             24.14           NaN         20.00          33.33           53.33           52.63           80.00           41.67           79.17            75.00
Missing                 NaN           NaN           NaN            NaN             NaN             NaN             NaN             NaN             NaN           100.00
Queenstown              NaN         37.21        100.00            NaN           66.67           37.50           60.00             NaN             NaN            50.00
Southampton           10.17         22.73         13.54          23.29           39.39           39.34           49.37           38.71           43.08            76.92