Zonebudget setup in MF-USG

[ccarson-tt]

I am working on an unstructured (voronoi) MF-USG model and want to setup zonebudget. I've created an array containing a zone value (integers 1 to 4) for each node in the model, but I'm running into issues when I try to instantiate the ZoneBudget object - currently getting this error which I think is related to the structure of the .cbb binary file:

Code:

zb = ZoneBudget(
cbc_file='usg_model.cbb',
z=zone_array,
aliases={1:'zone_1',
2:'zone_2',
3:'zone_3',
4:'zone_4',}
)

IndexError: boolean index did not match indexed array along dimension 2; dimension is 107262 but corresponding boolean dimension is 944586

For reference, the zone array variable looks like this:
array([[[4, 4, 4, ..., 2, 2, 2]]])
zone_array.shape:
(1, 1, 107262)

When I load up my .cbb file and run cbb.list_records() I get the following:

Any guidance here would be greatly appreciated!

Cheers,

Colter

[ccarson-tt]

UPDATE: I managed to successfully run zonbudusg.exe (running executable in model directory) by manually setting up a zone input file which looked like this (saved as mymodel.zif):

For the zone numbers array, I just pasted the zone values I generated in flopy by intersecting polygons with my model grid (107262 zone values - one for each node).