volume averaging between tree + tensor with different number of cells

[Lindsey Heagy]

I am running into an
ValueError: operands could not be broadcast together with shapes (33,) (29,)

When I am trying to perform the volume averaging between a tensor mesh and a tree mesh. The extent of the TreeMesh is smaller than the tensor, so I am not entirely sure where things are going awry

Here is a minimal example to reproduce the error:

import numpy as np
import discretize

pf = 1.3
npad = 5
nc = 20
cs = 5

nc_tree = 32

mesh_tensor = discretize.TensorMesh([
        [(cs, npad, -pf), (cs, nc-2), (cs, npad, pf)],
        [(cs, npad, -pf), (cs, nc-2), (cs, npad, pf)],
        [(cs, npad, -pf), (cs, nc-2), (cs, npad, pf)],
    ],
    x0 = "CCC"
)

mesh_tree = discretize.TreeMesh([
        [(cs, nc_tree)], [(cs, nc_tree)], [(cs, nc_tree)],
    ],
    x0 = "CCC"
)

mesh_tree = discretize.utils.refine_tree_xyz(
    mesh_tree, np.c_[0, 0, 0], octree_levels=[8, 4, 2], method="radial", finalize=True
)

sigma = np.random.rand(mesh_tensor.nC)

sigma_tree = discretize.utils.volume_average(mesh_tensor, mesh_tree, sigma)