Change the value of a column based on the value of another column with pandas

To clarify I’ll give an example:

• Dataframe has 2 columns: Currency and Price
• Currency has 3 unique values: EUR, GBP, USD
• I need to set the prices, as they are all in USD
• I need to multiply those values that are GBP and EUR with another double, i.e. 1.15 and 1.5 respectively.

>Solution :

Try something like:

df['value'][df['Currency'] == 'GBP'] = df['value'][df['Currency'] == 'GBP'] * GBP_factor