multiply the other columns if contains a string 'keyword' pandas python-CodePudding

I want to multiply the UNIT column by 2 if the string 'BUY2' is available in the Item Description Column.

DF:

UNIT | Item_Description
2    |  BUY1  
4    |  BUY1  
7    |  BUY2  
4    |  BUY3
12   |  BUY3

Code: not Working :(

if  DF['Item_Description'].str.contains('BUY2').any():
    DF['UNIT'] * 2
else:
    DF['UNIT']

CodePudding user response：

df = pd.DataFrame({"unit":[2,4,7,4,12],
                   "ID":["BUY1", "BUY1", "BUY2", "BUY3", "BUY3"]})

df["unit"] = np.where(df["ID"]=="BUY2", df["unit"]*2, df["unit"])

CodePudding user response：

You meant:

if  DF['Item_Description'].str.contains('BUY2').any():
    DF['UNIT'] *= 2

You need to assign it back.

It's the same logic as:

if  DF['Item_Description'].str.contains('BUY2').any():
    DF['UNIT'] = DF['UNIT'] * 2

Or if you want to do it on specific rows:

DF.loc[DF['Item_Description'].str.contains('BUY2'), 'UNIT'] *= 2