Question

developed_countries = ["NOR","AUS","CHE","DEU","DNK","SGP","NLD","IRL","ISL","CAN","USA","NZL","SWE","LIE","GBR"]

recent_indicators['Developed'] = np.where(recent_indicators['CountryCode'] in developed_countries, 1, 0)

＆＃34; ValueError：系列的真值是不明确的。使用a.empty， a.bool（），a.item（），a.any（）或a.all（）。＆＃34;

recent_indicators 是pandas DataFrame。什么可以替代检查＆＃39; CountryCode＆＃39;在develop_countries中提到了什么？

Answer 1

您可以直接在pandas过滤中使用.isin() -

recent_indicators_filtered = recent_indicators[recent_indicators['CountryCode'].isin(developed_countries)]

此外，您可以提出一个布尔列，如果已开发，则显示True -

recent_indicators['Developed'] = recent_indicators['CountryCode'].isin(developed_countries)

如何检查行中的数据是否在np.where（）内的列表中？

1 个答案: