def column_stack_2d ( data ) : return list ( list ( itt . chain . from_iterable ( _ ) ) for _ in zip ( * data ) )
how to stack column arrays in python
Perform column - stacking on a list of 2d data blocks .
def column_stack_2d(data):
    """Perform column-stacking on a list of 2d data blocks."""
    return list(list(itt.chain.from_iterable(_)) for _ in zip(*data))