Make interpolate_array GPU compatibile

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ClimaCore.jl/src/Remapping/interpolate_array.jl

Lines 1 to 34 in 9c22047

	function interpolate_slab(
	field::Fields.Field,
	slabidx::Fields.SlabIndex,
	(I1,)::Tuple{<:AbstractArray},
	)
	space = axes(field)
	x = zero(eltype(field))
	QS = Spaces.quadrature_style(space)
	Nq = Spaces.Quadratures.degrees_of_freedom(QS)
	for i in 1:Nq
	ij = CartesianIndex((i,))
	x += I1[i] * Operators.get_node(space, field, ij, slabidx)
	end
	return x
	end
	function interpolate_slab(
	field::Fields.Field,
	slabidx::Fields.SlabIndex,
	(I1, I2)::Tuple{<:AbstractArray, <:AbstractArray},
	)
	space = axes(field)
	x = zero(eltype(field))
	QS = Spaces.quadrature_style(space)
	Nq = Spaces.Quadratures.degrees_of_freedom(QS)
	for j in 1:Nq, i in 1:Nq
	ij = CartesianIndex((i, j))
	x += I1[i] * I2[j] * Operators.get_node(space, field, ij, slabidx)
	end
	return x
	end

These functions do not run on a GPU because of the explicit indexing.

A temporary workaround might be to make them vector/matrix multiplications by allocating locally a matrix with the values of the nodes. This might be acceptable for the moment, given that Nq is typically not very large and because this is done only when the diagnostic is output (which might be once every 12 hours).

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Closed by #1512