Question

I have a 3-dimensional point class whose hash function, according to the profiler, would be a good place to do some optimizing. Right now, I’m just passing a tuple of the coordinates to the built-in hash function:

def __hash__(self):
        return hash((self.x, self.y, self.z))

How can I make this faster? I’m assuming constructing a tuple each time isn’t good. The coordinates are real-valued.

Answer 1

Using a tuple instead of your own class will be much faster.

If you really want to write p.x instead of p[0] then you can make your class a subclass of tuple and have accessors. It will still be much faster than implementing your own tuple.

class Point3d(tuple):
    @property
    def x(self):
        return self[0]

    @property
    def y(self):
        return self[1]

    @property
    def z(self):
        return self[2]