根据Pandas中的多个条件选择列

Question

如何将SQL语句转换为Pandas：

select PolicyNumber, 
       Coverage 
  from  ClaimsData 
  where AccidentState = 'AZ' and Coverage = 'Liability'

我知道如何为单个条件（AccidentState ='AZ'）选择列，但是如何添加另一个条件？

ClaimsData[["PolicyNumber","Coverage","AccidentState"]] [ClaimsData["AccidentState"]=="AZ"]  # and here I need to add another condition

Answer 1

您可以按条件&链接条件按位AND并按条件DataFrame.loc按条件boolean indexing按行DataFrame.query和按list按列名按列进行过滤：

mask = (ClaimsData["AccidentState"]=="AZ") & (ClaimsData["Coverage"]=="Liability")
df = ClaimsData.loc[mask, ["PolicyNumber","Coverage"]]

就像@Sandeep Kadapa指出的那样，{{3}}可以替代：

q = "AccidentState == 'AZ' & Coverage == 'Liability'"
df = ClaimsData.query(q)[["PolicyNumber","Coverage"]]