如何在 x 轴上排序箱线图类别

Question

我有一个包含两列 ACQUISITION_CHANNEL 和 HOURS_WORKED_CUMULATIVE 的 df，我使用下面的代码将其绘制为抖动的条形图。我想对 x 轴上的类别进行排序，以便它们首先按最高中位数排序。

ACQUISITION_CHANNEL	HOURS_WORKED_CUMULATIVE
Referral	34
Job Platform	42
Referral	34
Offline	42
Referral	34
Digital	42

...

group = 'ACQUISITION_CHANNEL'
column = 'HOURS_WORKED_CUMULATIVE'
grouped = df.groupby(group)


names, vals, xs = [], [] ,[]

for i, (name, subdf) in enumerate(grouped):
    names.append(name)
    vals.append(subdf[column].tolist())
    xs.append(np.random.normal(i+1, 0.1, subdf.shape[0]))

plt.boxplot(vals, labels=names, showfliers=False )
ngroup = len(vals)
clevels = np.linspace(0., 1., ngroup)

for x, val, clevel in zip(xs, vals, clevels):
    plt.scatter(x, val, alpha=0.4, c='#1f77b4')

plt.title('Hours Worked by Acquisition Channel')
plt.xlabel('Acquisition Channel')
plt.ylabel('Total Hours Worked') 

Answer 1

您可以在绘制数据之前按中位数对数据进行排序。 This question有个好答案

meds = df2.median()
meds.sort_values(ascending=False, inplace=True)
df2 = df2[meds.index]
df2.boxplot()

Answer 2

您可以通过结合 seaborn 的 boxplot 和 stripplot 来简化构造：

import seaborn as sns
import pandas as pd
import numpy as np

group = 'ACQUISITION_CHANNEL'
column = 'HOURS_WORKED_CUMULATIVE'
df = pd.DataFrame({group: np.random.choice(['Referral', 'Job Platform', 'Offline', 'Digital'], 1000),
                   column: np.random.randint(10, 300, 1000) + np.random.randint(1, 30, 1000) ** 2})

x_order = df.groupby(group)[column].agg('median').sort_values(ascending=False).index
ax = sns.boxplot(data=df, x=group, order=x_order, y=column,
                 palette=['skyblue'], medianprops={'color':'orange'})
sns.stripplot(data=df, x=group, order=x_order, y=column, jitter=0.4, alpha=0.6, ax=ax)

stripplot 也可以替换为swarmplot:

sns.swarmplot(data=df, x=group, order=x_order, y=column, size=3, alpha=0.6, ax=ax)