Partition positive integer into units:
abjad> from abjad.tools import mathtools
abjad> mathtools.partition_integer_into_units(6)
[1, 1, 1, 1, 1, 1]
Partition negative integer into units:
abjad> mathtools.partition_integer_into_units(-5)
[-1, -1, -1, -1, -1]
Partition 0 into units:
abjad> mathtools.partition_integer_into_units(0)
[]
Return list of zero or more parts with absolute value equal to 1.