Deprecate function_*(::VectorValues, ::Int, ::VectorDofs)

[fredrikekre]

function_value, function_gradient, function_divergence, and function_curl together with CellVectorValues supports specifying the local dof vector using Vec entries. This patch deprecates this. There is no point in casting T to Vec, just to then recast to T for the evaluation. Deprecations are added, but in practice I estimate that zero people use this functionality.

[fredrikekre]

There are similar methods for CellScalarValues + vector dofs, that is at least somewhat useful, but I don't think anyone uses that either. Deprecate that too?

[termi-official]

Which ones are you referring to?

[fredrikekre]

Ferrite.jl/src/FEValues/common_values.jl

Lines 201 to 211 in 2fe73a2

	# TODO: Deprecate this, nobody is using this in practice...
	function function_gradient(::ScalarValued, fe_v::Values{dim}, q_point::Int, u::AbstractVector{Vec{dim,T}}) where {dim,T}
	n_base_funcs = getn_scalarbasefunctions(fe_v)
	length(u) == n_base_funcs || throw_incompatible_dof_length(length(u), n_base_funcs)
	@boundscheck checkquadpoint(fe_v, q_point)
	grad = zero(Tensor{2,dim,T})
	@inbounds for i in 1:n_base_funcs
	grad += u[i] ⊗ shape_gradient(fe_v, q_point, i)
	end
	return grad
	end