unzip a dictionary of coordinates and values

Question

I wish to populate the values x,y and z, where x are the x coordinates, y the y coordinates and z the associated values for each coordinate, as defined by p. Here is how I am doing it:

p = {(1,2): 10, (0,2):12, (2,0):11}
k,z = np.array(list(zip(*p.items())))
x,y = np.array(list(zip(*k)))

Is there another more readable way? Perhaps there is something in numpy or scipy for doing this?

Why does z result in array([10, 11, 12], dtype=object), while x an y do not include dtype=object?

Answer 1

How about as a one-liner?

x, y, z = np.array([(x, y, z) for (x, y), z in p.items()]).T

This makes it clearer where the values are coming from, without the unnecessary and unused k. Additionally, you should not have the dtype issue with this.