python 绘制并列条形图并添加数据标签

利用python绘制并列的条形图。
（1）处理数据，计算每个区间的个数：

（2）plt.bar函数绘制条形图：

df = pd.read_excel('path of file ',sheet_name='Sheet1')

area_class = df['name']

lake_num = df['lake_number']

TP_lake_num = df['TP_2020_lake_number']

bar_width = 0.3  

index_lake = np.arange(len(area_class))

index_TP = index_lake + bar_width

plt.bar(index_lake, height=lake_num, width=bar_width, color='b', label='study_2020_lake')

plt.bar(index_TP, height=TP_lake_num, width=bar_width, color='g', label='TP_2020_lake')

plt.legend() 

plt.xticks(index_lake + bar_width/2, area_class)  

plt.ylabel('Number') 

plt.xlabel('Area (km$^{2}$)') 

plt.show()

显示结果：

（3）图形优化
为每个柱添加数据标签：

df = pd.read_excel('path of file',sheet_name='Sheet1')

fig, ax = plt.subplots()

area_class = df['name']

lake_num = df['lake_number']

TP_lake_num = df['TP_2020_lake_number']

bar_width = 0.3  

index_lake = np.arange(len(area_class))

index_TP = index_lake + bar_width

plt.bar(index_lake, height=lake_num, width=bar_width, color='b', label='study_lake')

for x, y in enumerate(df['lake_number'].values):
    
    # plt.text(x, y+1,y,ha='center', va='bottom')
    
    plt.text(x+0.1, y+1,y,ha='right',va='bottom')
    
plt.bar(index_TP, height=TP_lake_num, width=bar_width, color='g', label='TP_lake')

for a, b in enumerate(df['TP_2020_lake_number'].values):
    
    plt.text(a+0.1, b+1,b,ha='left',va='bottom')
    
plt.legend() 

plt.xticks(index_lake + bar_width/2, area_class)  

plt.ylabel('Number') 

plt.xlabel('Area (km$^{2}$)') 

plt.show()

显示结果：

plt.text()函数参数说明：https://matplotlib.org/stable/api/_as_gen/matplotlib.pyplot.text.html