python - 在条形图上添加条形高度值和缺失值

Question

我确实喜欢在该条形图的输出上显示条形的高度数，并且还能够在条形图上包含用零表示的缺失值。这是我的数据集:

# intialise data of lists. 
data = {'Hospital_name':['Jootrh Hospital', 'Jootrh Hospital', 'Embu Hospital', 'Embu Hospital','Bungoma Hospital', 'Bungoma Hospital', 'Keru Hospital', 'Keru Hospital'], 
        'periodname':["18-Jul", "18-Aug", "18-Jul", "18-Aug","18-Jul", "18-Aug", "18-Jul", "18-Aug"], 'normal deliveries':[452, 458, "NAN", 45,498, 466, "NAN", 450],
       'caesarian sections':[67.0, 99.0, 13.0, 13.0,60.0, 19.0, 73.0, "NAN"], 'breach delivery':[10.0, "NAN", 13.0, 137.0,100.0, "NAN", "NAN" ,197.0],
       'assisted vd':["NAN", "NAN", 1.0, 37.0,1.0, "NAN", 1.0, 37.0]}


# Create DataFrame 
df = pd.DataFrame(data) 
df

这是我显示条形图的代码，但我确实希望包含缺失值和条形高度值。

import numpy as np
import matplotlib.pyplot as plt

df.set_index('periodname', inplace=True)
grouped = df.groupby('Hospital_name')

ncols=2
nrows = int(np.ceil(grouped.ngroups/ncols))

fig, axes = plt.subplots(nrows=nrows, ncols=ncols,figsize=(20,50),  constrained_layout=True)

for (key, ax) in zip(grouped.groups.keys(), axes.flatten()):
    grouped.get_group(key).plot(kind='bar',ax=ax, title=key)

ax.legend()
plt.show()

如何能够包含条形高度值并包含条形图上由零表示的缺失值？

预期输出是这样的:

Answer 1

您可能可以在绘图之前将所有“NAN”值替换为 0。

for (key, ax) in zip(grouped.groups.keys(), axes.flatten()):
    grouped.get_group(key).replace("NAN",0).plot(kind='bar',ax=ax, title=key)

这应该会导致每个周期有 4 个柱。

更新

有关每个条形的高度/值，请参阅 answer .

非常粗糙并且存在定位问题，这在您的代码中可能看起来像这样:

fig, axes = plt.subplots(nrows=nrows, ncols=ncols,figsize=(20,50),  constrained_layout=True)

x_offset = 0.02
y_offset = 0.02

for (key, ax) in zip(grouped.groups.keys(), axes.flatten()):

    temp = grouped.get_group(key).replace("NAN",0).plot(kind='bar',ax=ax, title=key)
    for bar in temp.patches:
        b = bar.get_bbox()
        val = "{:+.2f}".format(b.y1 + b.y0)        
        ax.annotate(val, ((b.x0 + b.x1)/2 + x_offset, b.y1 + y_offset))


ax.legend()
plt.show()