1 files changed, 77 insertions, 0 deletions
diff --git a/externals/gridflow/base/flow_objects_for_matrix.c b/externals/gridflow/base/flow_objects_for_matrix.c
new file mode 100644
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--- /dev/null
+++ b/externals/gridflow/base/flow_objects_for_matrix.c
@@ -0,0 +1,77 @@
+/*
+	$Id: flow_objects_for_matrix.c,v 1.1 2005-10-04 02:02:13 matju Exp $
+
+	GridFlow
+	Copyright (c) 2001,2002,2003 by Mathieu Bouchard
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation; either version 2
+	of the License, or (at your option) any later version.
+
+	See file ../COPYING for further informations on licensing terms.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the Free Software
+	Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+#include <math.h>
+#include "grid.h.fcs"
+
+// produce an upper triangular matrix with ones on the diagonal
+// will also affect any additional columns using the same row-operations
+
+void expect_complete_matrix (P<Dim> d) {
+	if (d->n!=2) RAISE("bletch");
+	if (d->get(0)>d->get(1)) RAISE("argh");
+}
+
+\class GridMatrixSolve < GridObject
+struct GridMatrixSolve : GridObject {
+	Numop *op_sub;
+	Numop *op_mul;
+	Numop *op_div;
+	PtrGrid matrix;
+	GridMatrixSolve() {
+		matrix.constrain(expect_complete_matrix);
+	}
+	\decl void initialize ();
+	\grin 0 float
+};
+
+GRID_INPUT(GridMatrixSolve,0,matrix) {
+	int n = matrix->dim->get(0); // # rows
+	int m = matrix->dim->get(1); // # columns
+	Pt<T> mat = (Pt<T>)*matrix;
+	for (int j=0; j<n; j++) {
+		op_div->map(m,mat+j*m,mat[j*m+j]);
+		for (int i=j+1; i<n; i++) {
+			STACK_ARRAY(T,row,m);
+			COPY(row,mat+j,m);
+			op_mul->map(m,row,mat[i*m+j]);
+			op_sub->zip(m,mat+i*m,row);
+		}
+	}
+	GridOutlet out(this,0,matrix->dim);
+	out.send(n*m,mat);
+} GRID_END
+
+\def void initialize () {
+	rb_call_super(argc,argv);
+	this->op_sub = op_sub;
+	this->op_mul = op_mul;
+	this->op_div = op_div;
+}
+
+\classinfo { IEVAL(rself,"install '#matrix_solve',1,1"); }
+\end class
+
+void startup_flow_objects_for_matrix () {
+	\startall
+}