Error in the test_prims_layer

[aguspesce]

I'm making the tesseroid_layer test and reading the test_prims_leyer.
So, I think that I noted an error when check if a layer of prisms is property constructed in line 96.
The original line is:

expected_top[1, 1], expected_bottom[1, 1] = reference, surface[1, 1]

But I think that it should be:

expected_top[1, 1], expected_bottom[1, 1] = reference[1, 1], surface[1, 1]

@santisoler... am I right?

[santisoler]

Thanks for opening this issue @aguspesce.

For the record, you are talking about this line:

harmonica/harmonica/tests/test_prism_layer.py

Line 96 in d7c4354

expected_top[1, 1], expected_bottom[1, 1] = reference, surface[1, 1]

The reference variable is defined in line 82:

harmonica/harmonica/tests/test_prism_layer.py

Line 82 in d7c4354

(easting, northing), surface, reference, _ = dummy_layer

And the dummy_layer is the return of the dummy_layer fixture:

harmonica/harmonica/tests/test_prism_layer.py

Lines 32 to 48 in d7c4354

	@pytest.fixture(params=("numpy", "xarray"))
	def dummy_layer(request):
	"""
	Generate dummy arrays for defining prism layers
	"""
	easting = np.linspace(-1, 3, 5)
	northing = np.linspace(7, 13, 4)
	shape = (northing.size, easting.size)
	reference = 0
	surface = np.arange(20, dtype=float).reshape(*shape)
	density = 2670 * np.ones(shape)
	if request.param == "xarray":
	easting = xr.DataArray(easting, dims=("easting",))
	northing = xr.DataArray(northing, dims=("northing",))
	reference, surface = xr.DataArray(reference), xr.DataArray(surface)
	density = xr.DataArray(density)
	return (easting, northing), surface, reference, density

As you can see, the reference variable is either a float or an xarray.DataArray with a single value, so line 96 is actually ok. If I would made your proposed change, I would get an error because the float doesn't have a [1, 1] element, it cannot be indexed.

Maybe defining the reference as an xarray.DataArray with a single value is confusing and misleading. We could change that if that's make the tests more readable.

---

Since this is not an actual bug, I'm removing the bug label from it.