[Solved] Compare values under multiple conditions of one column in Python

by


Try:

#Use pd.Categorical to ensure sorting if column is not lexicographical ordered.
df['type'] = pd.Categorical(df['type'], ordered=True, categories=['s1','s2','s3'])

df['result'] = df.sort_values('type').groupby('name')['value'].diff(-1)

df['result'] = df['result'].lt(0).mask(df['result'].isna(),'')

df

Output:

   index name type  value result
0      1    A   s1     20  False
1      2    A   s2     10       
2      3    B   s1     18   True
3      4    B   s2     32  False
4      5    B   s3     25

2

solved Compare values under multiple conditions of one column in Python