From 355f90da867b79dcf358da3d849d03856e8ebe24 Mon Sep 17 00:00:00 2001
From: Martyn Gigg <martyn.gigg@stfc.ac.uk>
Date: Thu, 30 Oct 2014 14:23:39 +0000
Subject: [PATCH] Remove call to copy constructor in V3D::distance
When called millions of times in a loop, e.g. Monte Carlo, then this can
make a noticeably difference.
Refs #10169
---
Code/Mantid/Framework/Kernel/src/V3D.cpp | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/Code/Mantid/Framework/Kernel/src/V3D.cpp b/Code/Mantid/Framework/Kernel/src/V3D.cpp
index 1710acb8373..1e602534913 100644
--- a/Code/Mantid/Framework/Kernel/src/V3D.cpp
+++ b/Code/Mantid/Framework/Kernel/src/V3D.cpp
@@ -482,9 +482,8 @@ V3D::cross_prod(const V3D& v) const
double
V3D::distance(const V3D& v) const
{
- V3D dif(*this);
- dif-=v;
- return dif.norm();
+ const double dx(x-v.x), dy(y-v.y), dz(z-v.z);
+ return sqrt(dx*dx +dy*dy + dz*dz);
}
/** Calculates the zenith angle (theta) of this vector with respect to another
--
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