Make pinv(::AbstractVector) return a RowVector

Also broaden from StridedVector to AbstractVector while at it and don't employ full matrix SVD.
JuliaLang · Aug 1, 2017 · 7926b11 · 7926b11
1 parent 1a43098
commit 7926b11
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diff --git a/base/linalg/dense.jl b/base/linalg/dense.jl
@@ -891,7 +891,6 @@ function pinv(A::StridedMatrix{T}) where T
     tol = eps(real(float(one(T))))*maximum(size(A))
     return pinv(A, tol)
 end
-pinv(a::StridedVector) = pinv(reshape(a, length(a), 1))
 function pinv(x::Number)
     xi = inv(x)
     return ifelse(isfinite(xi), xi, zero(xi))

diff --git a/base/linalg/generic.jl b/base/linalg/generic.jl
@@ -795,6 +795,17 @@ function inv(A::AbstractMatrix{T}) where T
     A_ldiv_B!(factorize(convert(AbstractMatrix{S}, A)), eye(S0, checksquare(A)))
 end
 
+function pinv(v::AbstractVector{T}, tol::Real=real(zero(T))) where T
+    res = similar(v, typeof(zero(T) / (abs2(one(T)) + abs2(one(T)))))'
+    den = sum(abs2, v)
+    if den <= tol^2
+        fill!(res, zero(eltype(res)))
+    else
+        res .= v' ./ den
+    end
+    return res
+end
+
 """
     \\(A, B)