[bug] Buffer dtype mismatch, expected 'npy_intp' but got 'double'

[JPXKQX]

What happened?

Some users using the cutout operation (from anemoi-datasets) have the following error when calculating area weights over these nodes:

Buffer dtype mismatch, expected 'npy_intp' but got 'double'

Thanks to Ophélia Miralles for raising this issue.

What are the steps to reproduce the bug?

import torch
from anemoi.graphs.nodes.attributes import AreaWeights   

nodes = torch.load("graph.pt")["data"]
AreaWeights().get_raw_values(nodes)

Version

anemoi-graphs 0.3.0 (scipy 1.12, 1.13, and 1.14)

Platform (OS and architecture)

x86_64 GNU/Linux

Relevant log output

Exception has occurred: ValueError       (note: full exception trace is shown but execution is paused at: _run_module_as_main)
Buffer dtype mismatch, expected 'npy_intp' but got 'double'

  File ".../python3.10/site-packages/_voronoi.pyx", line 37, in scipy.spatial._voronoi.sort_vertices_of_regions
  File ".../python3.10/site-packages/scipy/spatial/_spherical_voronoi.py", line 261, in sort_vertices_of_regions
    _voronoi.sort_vertices_of_regions(self._simplices, self.regions)
  File ".../python3.10/site-packages/scipy/spatial/_spherical_voronoi.py", line 264, in _calculate_areas_3d
    self.sort_vertices_of_regions()
  File ".../python3.10/site-packages/scipy/spatial/_spherical_voronoi.py", line 339, in calculate_areas
    return self._calculate_areas_3d()
  File ".../anemoi-graphs/src/anemoi/graphs/nodes/attributes.py", line 123, in get_raw_values
    area_weights = sv.calculate_areas()

Accompanying data

The sample test graph can be downloaded from the following link:

wget https://object-store.os-api.cci1.ecmwf.int/ml-tests/test-data/anemoi-graphs/test_graph.pt

Organisation

ECMWF & MeteoSwiss