使用matplotlib分组堆积条形图

Question

我想创建一个“分组百分比叠加条形图”，因为想要一个更好的名字。这是我的代码的一个简单的工作示例：

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

# Data
r = [0,1,2,3,4]
raw_data = {'PFHxA': [20, 1.5, 7, 10, 5], \
        'PFHpA': [5, 15, 5, 10, 15], \
        'PFOA': [2, 15, 18, 5, 10], \
        'PFNA': [2, 15, 18, 5, 10], \
        'PFDA': [2, 15, 18, 5, 10], \
        'PFUnDA': [2, 15, 18, 5, 10], \
        'PFHxS': [2, 15, 18, 5, 10], \
        'PFOS': [2, 15, 18, 5, 10]}
df = pd.DataFrame(raw_data)

# From raw value to percentage
totals = [i+j+k+l+m+n+o+p for i,j,k,l,m,n,o,p in zip(df['PFHxA'], 
df['PFHpA'], df['PFOA'], df['PFNA'], df['PFDA'], df['PFUnDA'], df['PFHxS'], 
df['PFOS'])]
PFHxA = [i / j * 100 for i,j in zip(df['PFHxA'], totals)]
PFHpA = [i / j * 100 for i,j in zip(df['PFHpA'], totals)]
PFOA = [i / j * 100 for i,j in zip(df['PFOA'], totals)]
PFNA = [i / j * 100 for i,j in zip(df['PFNA'], totals)]
PFDA = [i / j * 100 for i,j in zip(df['PFDA'], totals)]
PFUnDA = [i / j * 100 for i,j in zip(df['PFUnDA'], totals)]
PFHxS = [i / j * 100 for i,j in zip(df['PFHxS'], totals)]
PFOS = [i / j * 100 for i,j in zip(df['PFOS'], totals)]

# plot
barWidth = 0.85
names = ('A','B','C','D','E')
# Create PFHxA Bars
plt.bar(r, PFHxA, color='#A20101', edgecolor='white', width=barWidth, 
label="PFHxA")
# Create PFHpA Bars
plt.bar(r, PFHpA, bottom=PFHxA, color='#F44E54', edgecolor='white', 
width=barWidth, label="PFHpA")
# Create PFOA Bars
plt.bar(r, PFOA, bottom=[i+j for i,j in zip(PFHxA, PFHpA)], color='#FF9904', 
edgecolor='white', width=barWidth, label="PFOA")
# Create PFNA Bars
plt.bar(r, PFNA, bottom=[i+j+k for i,j,k in zip(PFHxA, PFHpA, PFOA)], 
color='#FDDB5E', edgecolor='white', width=barWidth, label="PFNA")
# Create PFDA Bars
plt.bar(r, PFDA, bottom=[i+j+k+l for i,j,k,l in zip(PFHxA, PFHpA, PFOA, 
PFNA)], color='#BAF1A1', edgecolor='white', width=barWidth, label="PFDA")
# Create PFUnDA Bars
plt.bar(r, PFUnDA, bottom=[i+j+k+l+m for i,j,k,l,m in zip(PFHxA, PFHpA, 
PFOA, PFNA, PFDA)], color='#76AD3B', edgecolor='white', width=barWidth, 
label="PFUnDA")
# Create PFHxS Bars
plt.bar(r, PFHxS, bottom=[i+j+k+l+m+n for i,j,k,l,m,n in zip(PFHxA, PFHpA, 
PFOA, PFNA, PFDA, PFUnDA)], color='#0A709A', edgecolor='white', 
width=barWidth, label="PFHxS")
# Create PFOS Bars
plt.bar(r, PFOS, bottom=[i+j+k+l+m+n+o for i,j,k,l,m,n,o in zip(PFHxA, 
PFHpA, PFOA, PFNA, PFDA, PFUnDA, PFHxS)], color='#5E3F99', 
edgecolor='white', width=barWidth, label="PFOS")


# Custom x axis
plt.xticks(r, names)
plt.xlabel("Sample ID")

# Custom y axis
plt.ylabel("Mass percentage")

# Add a legend
plt.legend(loc='upper left', bbox_to_anchor=(1,1), ncol=1)

# Show graphic
plt.show()

这很好用，我创建了以下百分比堆积条形图：。

但是，我想在样本B和C之间以及样本D和E之间添加一些额外的空白区域，因为我想强调有三个样本组（A和B是第一组，C和D是第二组，E是第三组）。有没有一种简单的方法可以做到这一点（这样我可以将它扩展到三组以上）？理想情况下，我还希望能够在每个组上方添加文本标签 - 这也可能吗？

Answer 1

对于询问条形之间的间距，代码似乎太复杂了，因为这是由r确定的，您可以将r更改为例如。

r = [0,1,2.5,3.5,5]

可以通过plt.text

添加文字

for pos, text in r, texts:
    plt.text(r, 101, text)