From 633ef15196e88a85f35d45cad5e0be6c68ea751b Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sat, 15 Aug 2009 01:45:20 +0000 Subject: [PATCH] Fix math error. git-svn-id: https://svn.dealii.org/trunk@19271 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/doc/doxygen/headers/multithreading.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/deal.II/doc/doxygen/headers/multithreading.h b/deal.II/doc/doxygen/headers/multithreading.h index 97a11df06d..58a4e10f4d 100644 --- a/deal.II/doc/doxygen/headers/multithreading.h +++ b/deal.II/doc/doxygen/headers/multithreading.h @@ -773,7 +773,8 @@ * point where we want to copy the local into the global contributions the * order is still as if we computed things sequentially. In other words, it * may happen that we add the contributions of cell 1 before those of cell - * 0. That may seem harmless because addition is commutative, but in fact it + * 0. That may seem harmless because addition is commutative and + * associative, but in fact it * is not if done in floating point arithmetic: $a+b+c \neq a+c+b$ -- take * for example $a=1, b=-1, c=10^{-20}$ (because $1+10^{-20}=1$ in floating * point arithmetic, using double precision). -- 2.39.5