From: wolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Fri, 14 Sep 2001 09:12:59 +0000 (+0000)
Subject: Add note.
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=45e9fd3ae007a40d5f15374887c32ae4d059494d;p=dealii-svn.git

Add note.


git-svn-id: https://svn.dealii.org/trunk@5000 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/deal.II/source/fe/mapping_q.cc b/deal.II/deal.II/source/fe/mapping_q.cc
index d55e0e821f..8799bb3bd9 100644
--- a/deal.II/deal.II/source/fe/mapping_q.cc
+++ b/deal.II/deal.II/source/fe/mapping_q.cc
@@ -83,9 +83,18 @@ MappingQ<1>::~MappingQ ()
 template<typename number>
 static number power(const number x, const unsigned int y)
 {
+				   // since the power to which x is
+				   // raised is usually the space
+				   // dimension, and since this is
+				   // rarely larger than three, the
+				   // following code is optimal and
+				   // cannot be further optimized by
+				   // grouping of operands to reduce
+				   // the number of multiplications
+				   // from O(x) to O(log x)
   number value=1;
   for (unsigned int i=0; i<y; ++i)
-    value*=x;
+    value *= x;
   return value;
 }