大熊猫数据变异百分比

Question

I此数据帧代码：

analytics = q1.groupby(['Year','YearMonth','glnumber','nom'])[['amount']].sum().reset_index()
#add previous sales to the next row
analytics['prev_$'] = analytics['amount'].shift(1)
#drop the null values and calculate the difference
analytics = analytics.dropna()
analytics['diff'] = (analytics['amount'] - analytics['prev_$'])
analytics = analytics.drop(['prev_$'],
  axis='columns')

我试图通过将分析“‘prev_$”除以“分析量”来计算变异百分比。

这是我的密码：

analytics['Perc_diff'] = analytics.apply(0 if analytics['amount'] == 0 else divide(analytics['diff'], analytics['amount']))

但是我有一个错误: ValueError:系列的真值是模棱两可的。使用a.empty、a.bool()、a.item()、a.any()或a.all()。

Answer 1

为此，您可以使用np.where：

import numpy as np
analytics['Perc_diff'] = np.where(analytics['amount']==0,0,analytics['diff']/analytics['amount'])