#2391 (#2367) Bail out before FPE.

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@19003 b5f69653-2bf5-0310-8201-b0dafb8e1405
Doxygen coverage

git-svn-id: https://chaste.cs.ox.ac.uk/svn/chaste/trunk@19004 b5f69653-2bf5-0310-8201-b0dafb8e1405