Allow trailing 1s for gridded & scaled (fixes #301) (#318)

src/gridded/indexing.jl

@@ -4,8 +4,16 @@
     wis = weightedindexes((value_weights,), itpinfo(itp)..., x)
     coefficients(itp)[wis...]
 end
+@propagate_inbounds function (itp::GriddedInterpolation{T,N})(x::Vararg{Number,M}) where {T,M,N}
+    inds, trailing = split_trailing(itp, x)
+    @boundscheck (check1(trailing) || Base.throw_boundserror(itp, x))
+    @assert length(inds) == N
+    itp(inds...)
+end
 @inline function (itp::GriddedInterpolation)(x::Vararg{UnexpandedIndexTypes})
-    itp(to_indices(itp, x)...)
+    xis = to_indices(itp, x)
+    xis == x && error("evaluation not supported for GriddedInterpolation at positions $x")
+    itp(xis...)
 end
 
 @inline function gradient(itp::GriddedInterpolation{T,N}, x::Vararg{Number,N}) where {T,N}

src/scaling/scaling.jl

@@ -67,6 +67,12 @@ ubound(ax::AbstractRange, ::DegreeBC, ::OnGrid) = last(ax)
     xl = maybe_clamp(sitp.itp, coordslookup(itpflag(sitp.itp), sitp.ranges, xs))
     @inbounds sitp.itp(xl...)
 end
+@propagate_inbounds function (itp::ScaledInterpolation{T,N})(x::Vararg{Number,M}) where {T,M,N}
+    inds, trailing = split_trailing(itp, x)
+    @boundscheck (check1(trailing) || Base.throw_boundserror(itp, x))
+    @assert length(inds) == N
+    itp(inds...)
+end
 @inline function (sitp::ScaledInterpolation)(x::Vararg{UnexpandedIndexTypes})
     xis = to_indices(sitp, x)
     xis == x && error("evaluation not supported for ScaledInterpolation at positions $x")

test/gridded/gridded.jl

@@ -85,4 +85,7 @@ using Interpolations, Test
     @test itp(2) === 2.0f0
     @test itp(2.0) === 2.0
     @test itp(2.0f0) === 2.0f0
+
+    # trailing 1s, issue #301
+    @test itp(1.8, 1) == itp(1.8)
 end

test/scaling/scaling.jl

@@ -14,6 +14,9 @@ using Test, LinearAlgebra, StaticArrays
     for (x,y) in zip(-3:.05:1.5, 1:.1:10,)
         @test sitp(x) ≈ y
     end
+    # trailing 1s, issue #301
+    @test sitp(0.8, 1) == sitp(0.8)
+
 
     @test_throws ArgumentError scale(itp, reverse(-3:.5:1.5))