From: wolf Date: Mon, 21 Jun 2004 20:01:24 +0000 (+0000) Subject: Improved CompressedSparsityPattern. X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=544bd4643786aeeb0cd4bb688fdc330c9c7959e0;p=dealii-svn.git Improved CompressedSparsityPattern. git-svn-id: https://svn.dealii.org/trunk@9445 0785d39b-7218-0410-832d-ea1e28bc413d --- diff --git a/deal.II/doc/news/c-5.0.html b/deal.II/doc/news/c-5.0.html index 5996b44f5d..d5cc31154b 100644 --- a/deal.II/doc/news/c-5.0.html +++ b/deal.II/doc/news/c-5.0.html @@ -98,6 +98,21 @@ inconvenience this causes.

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    +
  1. + Improved: The CompressedSparsityPattern + class used one of the C++ standard containers to store the column + indices of nonzero entries in a sparse matrix. This proved to be + inefficient since it requires the allocation of 20 bytes each time an + element was added, which for large matrices can be millions of + times. The new storage format uses a more compact data structure, and a + cache that requires memory allocation only every 8 additions, on + average. This should significantly reduce the total amount of memory + required as well as memory fragmentation. It also cuts run-time for + element addition by more than half. +
    + (WB 2004/06/21) +

    +
  2. Fixed: CompressedSparsityPattern::max_entries_per_row()