Multi tool use

Python pd using a variable with column name in groupby dot notation

I am trying to use a list that holds the column names for my groupby notation. My end goal is to loop through multiple columns and run the calculation without having to re-write the same line multiple times. Is this possible?

a_list = list(['','BTC_','ETH_'])
a_variable = ('{}ClosePrice'.format(a_list[0]))

proccessing_data['RSI'] = proccessing_data.groupby('Symbol').**a_variable**.transform(lambda x: talib.RSI(x, timeperiod=14))


this is the error I currently get because it thinks I want the column 'a_variable' which doesn't exist.

AttributeError: 'DataFrameGroupBy' object has no attribute 'a_variable'


df[a_variable]

df.a_variable

1 Answer
1

Apparently this notation below works:

proccessing_data['RSI'] = proccessing_data.groupby('Symbol')[('{}ClosePrice'.format(a_list[0]))].transform(lambda x: talib.RSI(x, timeperiod=14))


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