Merge pull request #271 from JuliaMath/teh/show

Add show method that circumvents bounds errors (fixes #260)

Author: timholy

src/io.jl

@@ -28,7 +28,11 @@ _showknots(io, A) = Base.showarg(io, A, false)
 function _showknots(io, tup::NTuple{N,Any}) where N
     print(io, '(')
     for (i, A) in enumerate(tup)
-        Base.showarg(io, A, false)
+        if A isa AbstractRange
+            show(io, A)
+        else
+            Base.showarg(io, A, false)
+        end
         i < N && print(io, ',')
     end
     N == 1 && print(io, ',')
@@ -77,3 +81,37 @@ function Base.showarg(io::IO, A::FilledExtrapolation{T,N,TI,IT}, toplevel) where
         print(io, " with element type ",T)
     end
 end
+
+"""
+    show_ranged(io, X, knots)
+
+A replacement for the default array-`show` for types that may not have the canonical evaluation points.
+`rngs` is the tuple of knots along each axis.
+"""
+function show_ranged(io::IO, X, knots)
+    summary(io, X)
+    isempty(X) && return
+    print(io, ":")
+    if !(haskey(io, :compact)) && length(axes(X, 2)) > 1
+        io = IOContext(io, :compact => true)
+    end
+    if get(io, :limit, false) && eltype(X) === Method
+        io = IOContext(io, :limit => false)
+    end
+    if get(io, :limit, false) && (displaysize(io))[1] - 4 <= 0
+        return print(io, " …")
+    else
+        println(io)
+    end
+    io = IOContext(io, :typeinfo => eltype(X))
+    Base.print_array(io, [X(x...) for x in Iterators.product(knots...)])
+end
+
+getknots(X::BSplineInterpolation)  = axes(X)
+getknots(X::ScaledInterpolation)   = X.ranges
+getknots(X::GriddedInterpolation)  = X.knots
+getknots(X::AbstractExtrapolation) = getknots(parent(X))
+
+Base.show(io::IO, ::MIME{Symbol("text/plain")}, X::ScaledInterpolation)   = show_ranged(io, X, getknots(X))
+Base.show(io::IO, ::MIME{Symbol("text/plain")}, X::GriddedInterpolation)  = show_ranged(io, X, getknots(X))
+Base.show(io::IO, ::MIME{Symbol("text/plain")}, X::AbstractExtrapolation) = show_ranged(io, X, getknots(X))

test/io.jl

@@ -40,12 +40,24 @@ using Test
 
         itp = interpolate(knots, A, (Gridded(Linear()),Gridded(Constant())))
         @test summary(itp) == "8×20 interpolate((::Array{Int64,1},::Array{Float64,1}), ::Array{Float64,2}, (Gridded(Linear()), Gridded(Constant()))) with element type Float64"
+
+        # issue #260
+        A = (1:4)/4
+        itp = interpolate((range(0.0, stop=0.3, length=4),), A, Gridded(Linear()))
+        io = IOBuffer()
+        show(io, MIME("text/plain"), itp)
+        str = String(take!(io))
+        @test str == "4-element interpolate((0.0:0.1:0.3,), ::Array{Float64,1}, Gridded(Linear())) with element type Float64:\n 0.25\n 0.5 \n 0.75\n 1.0 "
     end
 
     @testset "scaled" begin
         itp = interpolate(1:1.0:10, BSpline(Linear()))
         sitp = scale(itp, -3:.5:1.5)
         @test summary(sitp) == "10-element scale(interpolate(::Array{Float64,1}, BSpline(Linear())), (-3.0:0.5:1.5,)) with element type Float64"
+        io = IOBuffer()
+        show(io, MIME("text/plain"), sitp)
+        str = String(take!(io))
+        @test str == "10-element scale(interpolate(::Array{Float64,1}, BSpline(Linear())), (-3.0:0.5:1.5,)) with element type Float64:\n  1.0\n  2.0\n  3.0\n  4.0\n  5.0\n  6.0\n  7.0\n  8.0\n  9.0\n 10.0"
 
         gauss(phi, mu, sigma) = exp(-(phi-mu)^2 / (2sigma)^2)
         testfunction(x,y) = gauss(x, 0.5, 4) * gauss(y, -.5, 2)
@@ -74,4 +86,22 @@ using Test
         etpf = extrapolate(itpg, NaN)
         @test summary(etpf) == "8×20 extrapolate(interpolate(::Array{Float64,2}, BSpline(Linear())), NaN) with element type Float64"
     end
+
+    @testset "Combinations" begin
+        xs = 1.0:0.5:2.0
+        ys = xs.^3
+        interp_cubic = CubicSplineInterpolation(xs, ys)
+        io = IOBuffer()
+        show(io, MIME("text/plain"), interp_cubic)
+        str = String(take!(io))
+        @test occursin("3.375", str)
+    end
+
+    @testset "Issue #260" begin
+        itp = scale(interpolate(zeros(3,3,3),BSpline(Cubic(Free(OnGrid())))),2:4,2:4,2:4)
+        io = IOBuffer()
+        show(io, MIME("text/plain"), itp)
+        str = String(take!(io))
+        @test str == "3×3×3 scale(interpolate(OffsetArray(::Array{Float64,3}, 0:4, 0:4, 0:4), BSpline(Cubic(Free(OnGrid())))), (2:4, 2:4, 2:4)) with element type Float64:\n[:, :, 1] =\n 0.0  0.0  0.0\n 0.0  0.0  0.0\n 0.0  0.0  0.0\n\n[:, :, 2] =\n 0.0  0.0  0.0\n 0.0  0.0  0.0\n 0.0  0.0  0.0\n\n[:, :, 3] =\n 0.0  0.0  0.0\n 0.0  0.0  0.0\n 0.0  0.0  0.0"
+    end
 end # testset