From: wolf
Date: Thu, 17 Mar 2005 14:40:30 +0000 (+0000)
Subject: Add a paragraph about complex-valued problems.
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=14d2fe2bfa231002d30f1ef58ad4b03223648624;p=dealii-svn.git
Add a paragraph about complex-valued problems.
git-svn-id: https://svn.dealii.org/trunk@10182 0785d39b-7218-0410-832d-ea1e28bc413d
---
diff --git a/deal.II/doc/faq.html b/deal.II/doc/faq.html
index 4b409d7e5f..f9d7902b6c 100644
--- a/deal.II/doc/faq.html
+++ b/deal.II/doc/faq.html
@@ -43,6 +43,7 @@
deal.II?
How do I solve problem XXX with
deal.II?
+ Can I solve problems over complex numbers?
There is no tutorial program for
time-dependent problems!
I want to contribute to the development
@@ -397,6 +398,27 @@
+
+ Can I solve problems over complex numbers?
+
+
+ Yes, you can, and it has been done numerous times with
+ deal.II. However, we have a standard
+ recommendation: consider such problems as systems of partial
+ differential equations, where the individual components of the
+ solution are the real and imaginary part of your unknown. The reason
+ for this is that for complex-valued problems, the product
+ <u,v> of two vectors is not the same as
+ <v,u>, and it is very easy to get this wrong in many
+ places. If you want to avoid these common traps, then the easiest
+ way around is to split up you equation into two equations of real
+ and imaginary part first, and then treat the resulting system as a
+ system of real variables. This also makes the type of linear system
+ clearer that you get after discretization, and tells you something
+ about which solver may be adequate for it.
+
+
+
There is no tutorial program for
time-dependent problems!