BUG: funeval returns a 0 dimensional array when BasisStructure has single point

Issue by spencerlyon2
Friday Jul 31, 2015 at 02:16 GMT
Originally opened as https://github.com/QuantEcon/CompEcon.jl/issues/10

Test case:

using CompEcon
basis = Basis(ChebParams(10, -1, 1), ChebParams(5, 2, 4));
grid = nodes(basis)[1];
y = grid[:, 1] - grid[:, 2];  # simple function x - y
c = funfitxy(basis, grid, y)[1];
pt = [0.5, 2.1];
bs = BasisStructure(basis, Direct(), pt);
funeval(c, bs)

REPL example:

julia> using CompEcon

julia> basis = Basis(ChebParams(10, -1, 1), ChebParams(5, 2, 4));


julia> grid = nodes(basis)[1];

julia> y = grid[:, 1] - grid[:, 2];  # simple function x - y

julia> c = funfitxy(basis, grid, y)[1];

julia> pt = [0.5, 2.1];

julia> bs = BasisStructure(basis, Direct(), pt);

julia> funeval(c, bs)
0-dimensional Array{Float64,0}:
-1.6

Start by running the Julia reproduction with BasisStructure(basis, Direct(), pt), then trace the funeval entry point and the Direct basis evaluation path. Check how the single-point result is shaped and add or update a regression test for this case. Done means the shown evaluation no longer returns a 0-dimensional array.