Python: pandas dataframe condition for slice of a dataframe
dataframe, pandas, python
Solution
The warning is caused by the chained indexing (first making a slice and then using `.loc` on that slice). `df['Item']=='ABC'` is just another condition that you can use in `.loc`:
df.loc[con1 & con2 & (df['Item']=='ABC'), 'Item'] = 'ABCD'
Problem
I want to change the content in a slice of the pandas dataframe column that has 'ABC' ONLY in the column if the condition is fulfill. I try the code as below but it return this error ``` A value is trying to be set on a copy of a slice from a DataFrame.Try using .loc[row_indexer,col_indexer] = value instead ``` ``` print df Item Price Quantity 0 ABC 10 30 1 ABB 20 50 2 ABC 37 89 3 ABG 5 78 con1 = df['Price']>10 con2 = df['Quantity']>20 df[df['Item']=='ABC'].loc[con1 & con2,'Item'] = 'ABCD' Output that I want Item Price Quantity 0 ABC 10 30 1 ABB 20 50 2 ABCD 37 89 3 ABG 5 78 ```