python - Pandas:if 语句有错误: 'single positional indexer is out-of-bounds' then else

Question

我想做的是:

if df.loc[df['proba'] <= proba_plus].iloc[0]不是single positional indexer is out-of-bounds

然后:gamma_plus = df.loc[df['proba'] <= proba_plus].iloc[0]

else gamma_plus =df['gamma'].max()

知道如何做到这一点吗？谢谢!

Answer 1

您可以将 if-else 语句与 Series.empty 一起使用:

a = df.loc[df['proba'] <= proba_plus, 'gamma']
gamma_plus = df['gamma'].max() if a.empty else a.iat[0]

或者将next与iter一起使用 - 如果Series为空，则可以设置默认值:

a = df.loc[df['proba'] <= proba_plus, 'gamma']
gamma_plus = next(iter(a, df['gamma'].max()))