add Clenshaw tests

Author: dlfivefifty

src/clenshaw.jl

@@ -76,15 +76,15 @@ end
 
 function clenshaw!(c::AbstractMatrix, A::AbstractVector, B::AbstractVector, C::AbstractVector, x::Number, ϕ₀::Number, f::AbstractVector)
     size(c,2) == length(f) || throw(DimensionMismatch("coeffients size and output length must match"))
-    for j in axes(c,2)
+    @inbounds for j in axes(c,2)
         f[j] = ϕ₀ * clenshaw(view(c,:,j), A, B, C, x)
     end
     f
 end
 
 function clenshaw!(c::AbstractMatrix, A::AbstractVector, B::AbstractVector, C::AbstractVector, x::AbstractVector, ϕ₀::AbstractVector, f::AbstractMatrix)
     (size(x,1),size(c,2)) == size(f) || throw(DimensionMismatch("coeffients size and output length must match"))
-    for j in axes(c,2)
+    @inbounds for j in axes(c,2)
         clenshaw!(view(c,:,j), A, B, C, x, ϕ₀, view(f,:,j))
     end
     f
@@ -188,4 +188,22 @@ function clenshaw(c::AbstractVector, x::Number)
     end
 end
 
+function clenshaw!(c::AbstractMatrix, x::Number, f::AbstractVector)
+    size(c,2) == length(f) || throw(DimensionMismatch("coeffients size and output length must match"))
+    @inbounds for j in axes(c,2)
+        f[j] = clenshaw(view(c,:,j), x)
+    end
+    f
+end
+
+function clenshaw!(c::AbstractMatrix, x::AbstractVector, f::AbstractMatrix)
+    (size(x,1),size(c,2)) == size(f) || throw(DimensionMismatch("coeffients size and output length must match"))
+    @inbounds for j in axes(c,2)
+        clenshaw!(view(c,:,j), x, view(f,:,j))
+    end
+    f
+end
+
 clenshaw(c::AbstractVector, x::AbstractVector) = clenshaw!(c, copy(x))
+clenshaw(c::AbstractMatrix, x::Number) = clenshaw!(c, x, Vector{promote_type(eltype(c),typeof(x))}(undef, size(c,2)))
+clenshaw(c::AbstractMatrix, x::AbstractVector) = clenshaw!(c, x, Matrix{promote_type(eltype(c),eltype(x))}(undef, size(x,1), size(c,2)))

test/clenshawtests.jl

@@ -30,6 +30,12 @@ import FastTransforms: clenshaw, clenshaw!, forwardrecurrence!, forwardrecurrenc
                 # modifies x and xv
                 @test clenshaw!(cv2, xv) == xv == x == clenshaw([1,3], elty[1,0,0.1])
             end
+
+            @testset "matrix coefficients" begin
+                c = [1 2; 3 4; 5 6]
+                @test clenshaw(c,0.1) ≈ [clenshaw(c[:,1],0.1), clenshaw(c[:,2],0.1)]
+                @test clenshaw(c,[0.1,0.2]) ≈ [clenshaw(c[:,1], 0.1) clenshaw(c[:,2], 0.1); clenshaw(c[:,1], 0.2) clenshaw(c[:,2], 0.2)] 
+            end
         end
     end
 
@@ -46,6 +52,12 @@ import FastTransforms: clenshaw, clenshaw!, forwardrecurrence!, forwardrecurrenc
         c = [1,2,3]
         @test c'forwardrecurrence(3, A, B, C, 0.1) ≈ clenshaw([1,2,3], A, B, C, 0.1) ≈ 
             1 + (2sin(2acos(0.1)) + 3sin(3acos(0.1)))/sqrt(1-0.1^2)
+
+        @testset "matrix coefficients" begin
+            c = [1 2; 3 4; 5 6]
+            @test clenshaw(c,A,B,C,0.1) ≈ [clenshaw(c[:,1],A,B,C,0.1), clenshaw(c[:,2],A,B,C,0.1)]
+            @test clenshaw(c,A,B,C,[0.1,0.2]) ≈ [clenshaw(c[:,1], A,B,C,0.1) clenshaw(c[:,2], A,B,C,0.1); clenshaw(c[:,1], A,B,C,0.2) clenshaw(c[:,2], A,B,C,0.2)] 
+        end            
     end
 
     @testset "Chebyshev-as-general" begin