From 69a9a20eb816308eff293af58235bf43bca05829 Mon Sep 17 00:00:00 2001
From: Dave Goodwin <dgg@caltech.edu>
Date: Sun, 11 Feb 2007 16:27:38 +0000
Subject: [PATCH] added option to specify domain bandwidths

---
 Cantera/src/oneD/Domain1D.h | 27 +++++++++++++++++++++++++++
 Cantera/src/oneD/OneDim.cpp |  9 +++++++--
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/Cantera/src/oneD/Domain1D.h b/Cantera/src/oneD/Domain1D.h
index 217c863f7..d02481d38 100644
--- a/Cantera/src/oneD/Domain1D.h
+++ b/Cantera/src/oneD/Domain1D.h
@@ -91,6 +91,32 @@ namespace Cantera {
             m_index = index;
         }
 
+        /*
+         * Set the Jacobian bandwidth. See the discussion of method bandwidth. 
+         */
+        void setBandwidth(int bw = -1) {
+            m_bw = bw;
+        }
+
+        /**
+         * Set the Jacobian bandwith for this domain.  When class
+         * OneDim computes the bandwidth of the overall multi-domain
+         * problem (in OneDim::resize()), it calls this method for the
+         * bandwidth of each domain. If setBandwidth has not been
+         * called, then a negative bandwidth is returned, in which
+         * case OneDim assumes that this domain is dense -- that is,
+         * at each point, all components depend on the value of all
+         * other components at that point. In this case, the bandwidth
+         * is bw = 2*nComponents() - 1. However, if this domain
+         * contains some components that are uncoupled from other
+         * components at the same point, then this default bandwidth
+         * may greatly overestimate the true bandwidth, with a
+         * substantial penalty in performance. For such domains, use
+         * method setBandwidth to specify the bandwidth before passing
+         * this domain to the Sim1D or OneDim constructor.
+         */
+        int bandwidth() { return m_bw; }
+
         /**
          * Initialize. This method is called by OneDim::init() for
          * each domain once at the beginning of a simulation. Base
@@ -471,6 +497,7 @@ namespace Cantera {
         Refiner* m_refiner;
         vector_int m_td;
         std::vector<std::string> m_name;
+        int m_bw;
 
     private:
 
diff --git a/Cantera/src/oneD/OneDim.cpp b/Cantera/src/oneD/OneDim.cpp
index b01a4b03f..1ddf27493 100644
--- a/Cantera/src/oneD/OneDim.cpp
+++ b/Cantera/src/oneD/OneDim.cpp
@@ -171,12 +171,17 @@ namespace Cantera {
             int bw1, bw2 = 0;
 
             // bandwidth of the local block
-            bw1 = 2*d->nComponents() - 1;
+            bw1 = d->bandwidth();
+            if (bw1 < 0) 
+                bw1 = 2*d->nComponents() - 1;
 
             // bandwidth of the block coupling the first point of this
             // domain to the last point of the previous domain
             if (i > 0) {
-                bw2 = d->nComponents() + m_dom[i-1]->nComponents() - 1;
+                bw2 = m_dom[i-1]->bandwidth();
+                if (bw2 < 0) 
+                    bw2 = m_dom[i-1]->nComponents();
+                bw2 += d->nComponents() - 1;
             }
             if (bw1 > m_bw) m_bw = bw1;
             if (bw2 > m_bw) m_bw = bw2;