cudf.core.groupby.groupby.GroupBy.transform

GroupBy.transform(function)

Apply an aggregation, then broadcast the result to the group size.

Parameters:

function: str or callable

Aggregation to apply to each group. Note that the set of operations currently supported by transform is identical to that supported by the agg method.

Returns:

A Series or DataFrame of the same size as the input, with the

result of the aggregation per group broadcasted to the group

size.

See also

agg

Examples

import cudf
df = cudf.DataFrame({'a': [2, 1, 1, 2, 2], 'b': [1, 2, 3, 4, 5]})
df.groupby('a').transform('max')
   b
0  5
1  3
2  3
3  5
4  5