Divide scalar proportionally by ratio. Return list of len(ratio) parts.
abjad> mathtools.divide_scalar_by_ratio(Rational(1, 2), [1, 1, 3])
[Rational(1, 10), Rational(1, 10), Rational(3, 10)]
abjad> mathtools.divide_scalar_by_ratio(1, [1, 1, 3])
[0.20000000000000001, 0.20000000000000001, 0.59999999999999998]
Raise TypeError on nonnumeric scalar:
abjad> mathtools.divide_scalar_by_ratio('foo', [1, 1, 3])
TypeError
Todo
Do we want mathtools.divide_scalar_by_ratio(1, [1, 1, 3]) to return rational values instead of floats?