trouble with pcolor

Hi, I am trying to use pcolor to visualise three variables. For example if I have a value for z at x and a value for z at y something like [x1, x2, x3] = [z1, z2, z3] and [y1, y2, y3] = [z2, z1, z3]. Then I use meshgrid to create the grid for x and y,
X, Y = meshgrid(x, y)
the result is two array’s of shape (3,3).
I then need to reshape Z to use pcolor, which is what I am having trouble with. I know I want a result like,

y3 0 0 z3

y2 z1 0 0

y1 0 z2 0

 x1 x2 x3

but have no idea how to create it. Anyone able to help??
thanks
D