Accommodate edge case of single row or column (#8)

Author: RalphAS

src/GenericSVD.jl

@@ -97,6 +97,9 @@ then applying a Golub-Kahan QR iteration.
 """
 function svd!{T<:Real}(B::Bidiagonal{T}, U=nothing, Vt=nothing, ɛ=eps(T))
     n = size(B, 1)
+    if n == 1
+        @goto done
+    end
     n₂ = n
 
     maxB = max(maximum(abs, B.dv), maximum(abs, B.ev))

test/bigfloat.jl

@@ -74,3 +74,18 @@ bS = svdfact(bX)
 @test isapprox(full(bS), bX, rtol=1e3*eps(BigFloat))
 @test isapprox(svdvals(bX), svdvals(X), rtol=1e3*eps())
 @test bX == X # check we didn't modify the input
+
+n = 100
+X = randn(n,1)
+bX = big.(X)
+bS = svdfact(bX)
+@test isapprox(full(bS), bX, rtol=1e3*eps(BigFloat))
+@test isapprox(svdvals(bX), svdvals(X), rtol=1e3*eps())
+@test bX == X # check we didn't modify the input
+
+X = randn(1,n)
+bX = big.(X)
+bS = svdfact(bX)
+@test isapprox(full(bS), bX, rtol=1e3*eps(BigFloat))
+@test isapprox(svdvals(bX), svdvals(X), rtol=1e3*eps())
+@test bX == X # check we didn't modify the input