Re: [pygame] Pygame 2D vector

[Greg Ewing <greg.ewing@xxxxxxxxxxxxxxxx>]

sam.hacking@xxxxxxxx wrote:

> It has a get_angle() function, the first line of this checks if 
> length_sqrd() == 0, and then returns the angle as 0. This seems wrong to 
> me, if the vector is (1,-1), then length_sqrd (1**2 + -1**2) returns 0,

You're fooling yourself with operator precedence. If you're
typing that into the interactive interpreter, you need to
write it as

    1**2 + (-1)**2

which has the value 2.

The code given for get_length_sqrd() is

    return self.x**2 + self.y**2

which won't suffer from that problem.

--
Greg