svd(::Diagonal) speedup

Author: pabloferz

base/linalg/diagonal.jl

@@ -338,9 +338,9 @@ svdvals(D::Diagonal) = [svdvals(v) for v in D.diag]
 function svd{T<:Number}(D::Diagonal{T})
     S   = abs.(D.diag)
     piv = sortperm(S, rev = true)
-    U   = Array(Diagonal(D.diag ./ S))
+    U   = Diagonal(D.diag ./ S)
     Up  = hcat([U[:,i] for i = 1:length(D.diag)][piv]...)
-    V   = eye(D)
+    V   = Diagonal(ones(D.diag))
     Vp  = hcat([V[:,i] for i = 1:length(D.diag)][piv]...)
     return (Up, S[piv], Vp)
 end