import bpy
import random


# this assumes you have copied the vertexAccumulator.py script 
# into another text buffer named 'vertexAccumulator'
exec(bpy.data.texts['vertexAccumulator.py'].as_string())


def randomSquareArray(name, nu, nv):
    va = VertexAccumulator()
    faces = []
    for u in range(nu):
        for v in range(nv):
            z=random.randint(0,2)*0.5
            v1 = va.idxFor( [u, v, z] )
            v2 = va.idxFor( [u+1, v, z] )
            v3 = va.idxFor( [u+1, v+1, z] )
            v4 = va.idxFor( [u, v+1, z] )
            faces.append( [v1, v2, v3, v4] )

    mesh = bpy.data.meshes.new(name)
    mesh.from_pydata(va.verts(), [], faces)
    mesh.validate(True)
    
    obj = bpy.data.objects.new(name, mesh)
    bpy.context.scene.objects.link(obj)


randomSquareArray("grid", 11, 7)