Quickstart

Assign Columns

import pandas as pd

from colassigner import ColAssigner

class Cols(ColAssigner):
    def col1(self, df):
        return df.iloc[:, 0] * 2

    def col2(self, df):
        return "added-another"

df = pd.DataFrame({"a": [1, 2, 3]}).pipe(Cols())

df

	a	col_1	col_2
0	1	2	added-another
1	2	4	added-another
2	3	6	added-another

df.loc[:, Cols.col2]

0    added-another
1    added-another
2    added-another
Name: col_2, dtype: object

Access Columns

while also documenting datatypes

from colassigner import ColAccessor

class Cols(ColAccessor):

    x = int
    y = float

df = pd.DataFrame({Cols.x: [1, 2, 3], Cols.y: [0.3, 0.1, 0.9]})

df

	x	y
0	1	0.3
1	2	0.1
2	3	0.9

df.loc[:, Cols.y]

0    0.3
1    0.1
2    0.9
Name: y, dtype: float64