Vector operators

[ZacZhangzhuo]

Describe the bug

for Vector peration *, like:

>>> u = Vector(1.000, 1.000, 0.000)
>>> u * 2
Vector(2.000, 2.000, 0.000)

if we do: Vector * float: It is fine. float * Vector: TypeError: unsupported operand type(s) for *: 'float' and 'Vector'.

Expected behavior I think this could be fixed with minimal effort just for a better user experience. :)

[gonzalocasas]

Can it really be solved easily? I have the feeling it's not possible to define the binding of the star operator to take right hand operand as precedence...

[tomvanmele]

yes, we could implement the "r" versions of the magic methods, but i don't know if there would be any unwanted side-effects...

def __rmul__(self, factor):
    ...

[gonzalocasas]

Ah true 👍

[ZacZhangzhuo]

yes, it's not a big issue. mathmatically the floating number is preferred in the front. like a = k b, a, b are vectors.

[jf---]

@tomvanmele you're right that rmul would address the issue, and @ZacZhangzhuo is right in that operators in Vectors should be complete -- but float * Vector is quite counter intuitive?

[tomvanmele]

i agree, that is why never implemented the "r" versions. i think it is easy enough for the user to be explicit about their intent by writing the compas object first...

[jf---]

@tomvanmele I know I'm being frantic, but seems like this issue can be closed? The broader concept of vec ops isn't discussed.

[xarthurx]

@tomvanmele you're right that rmul would address the issue, and @ZacZhangzhuo is right in that operators in Vectors should be complete -- but float * Vector is quite counter intuitive?

It is actually quite common and intuitive, especially when you compute a "WEIGHTED * long-expression"....