Merge pull request #179 from JuliaMath/teh/fix_178

Fix computation of element type (fixes #178)

Author: timholy

src/b-splines/indexing.jl

@@ -94,10 +94,6 @@ function getindex_return_type(::Type{BSplineInterpolation{T,N,TCoefs,IT,GT,Pad}}
     _promote_mul(eltype(TCoefs), I)
 end
 
-@noinline function getindex_return_type(::Type{Tel}, ::Type{BSplineInterpolation{T,N,TCoefs,IT,GT,Pad}}, argtypes::Tuple) where {Tel,T,N,TCoefs,IT<:DimSpec{BSpline},GT<:DimSpec{GridType},Pad}
-    reduce(_promote_mul, eltype(TCoefs), (Tel, argtypes...))
-end
-
 @generated function gradient!(g::AbstractVector, itp::BSplineInterpolation{T,N}, xs::Number...) where {T,N}
     length(xs) == N || error("Can only be called with $N indexes")
     gradient_impl(itp)

src/extrapolation/filled.jl

@@ -21,7 +21,7 @@ function getindex_impl(fitp::Type{FilledExtrapolation{T,N,ITP,IT,GT,FT}}, args)
     n = length(args)
     n == N || return error("Must index $(N)-dimensional interpolation objects with $(nindexes(N))")
 
-    Tret = FT<:Number ? getindex_return_type(T, ITP, args) : FT
+    Tret = FT<:Number ? getindex_return_type(ITP, (T, args...)) : FT
     meta = Expr(:meta, :inline)
     quote
         $meta

test/extrapolation/runtests.jl

@@ -81,7 +81,10 @@ etp100g = extrapolate(interpolate(([10;20],),[100;110], Gridded(Linear())), Flat
 @test @inferred(getindex(etp100g, 5)) == 100
 @test @inferred(getindex(etp100g, 15)) == 105
 @test @inferred(getindex(etp100g, 25)) == 110
-
+# issue #178
+a = randn(10,10) + im*rand(10,10)
+etp = @inferred(extrapolate(interpolate((1:10, 1:10), a, Gridded(Linear())), 0.0))
+@test @inferred(etp[-1,0]) === 0.0+0.0im
 
 # check all extrapolations work with vectorized indexing
 for E in [0,Flat(),Linear(),Periodic(),Reflect()]