arrays - Is multiplication always commutative in inexact floating point arithmetic?

Question

I'm trying to understand some code in the D language runtime. It seems like there are separate functions for the following two things:

array1[] += scalar * array2[];
array1[] += array2[] * scalar;

Why can't these be done with one function? I thought multiplication was commutative even in inexact floating-point arithmetic.

Answer 1

I guess the difference is just in the function prototypes - one is (double, double[]) and the other is (double[], double). But the result should be the same either way.