Get column index from column name in python pandas

python pandas dataframe indexing
ak3nat0n picture ak3nat0n · Oct 23, 2012 · Viewed 336k times · Source

In R when you need to retrieve a column index based on the name of the column you could do

idx <- which(names(my_data)==my_colum_name)

Is there a way to do the same with pandas dataframes?

Answer

DSM picture DSM · Oct 23, 2012

Sure, you can use .get_loc():

In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [3,4,5]})

In [46]: df.columns
Out[46]: Index([apple, orange, pear], dtype=object)

In [47]: df.columns.get_loc("pear")
Out[47]: 2

although to be honest I don't often need this myself. Usually access by name does what I want it to (df["pear"], df[["apple", "orange"]], or maybe df.columns.isin(["orange", "pear"])), although I can definitely see cases where you'd want the index number.

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