From bf295af9caddf88106b66900a8f6528a996b875a Mon Sep 17 00:00:00 2001
From: Daniel Karrasch <daniel.karrasch@posteo.de>
Date: Fri, 29 Jul 2022 18:09:02 +0200
Subject: [PATCH] Replace inefficient broadcast with `copyto!` (#438)

* Replace inefficient broadcast with `copyto!`

* Update src/polynomials/ngcd.jl

Co-authored-by: Daniel Karrasch <daniel.karrasch@posteo.de>

Co-authored-by: john verzani <jverzani@gmail.com>
---
 src/polynomials/ngcd.jl | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/polynomials/ngcd.jl b/src/polynomials/ngcd.jl
index ec48949a..b54eeab7 100644
--- a/src/polynomials/ngcd.jl
+++ b/src/polynomials/ngcd.jl
@@ -266,7 +266,9 @@ function ngcd(p::PnPolynomial{T,X},
 
     nr, nc = size(Sₓ) # m+1, m-n+2
     F = qr(Sₓ)
-    Q[1:nr, 1:nr] .= F.Q
+    dest = view(Q, 1:nr, 1:nr)
+    copyto!(dest, I)
+    lmul!(F.Q, dest)
     R[1:nc, 1:nc] .= F.R
 
     # tolerances