From 9d6f0267f9c4d085adcde63dda462a3456766c27 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <sven@cs.kuleuven.be>
Date: Wed, 24 Dec 2008 22:56:12 +0100
Subject: [PATCH] vector_partition_chambers: computes chambers of vector
 partition function

Requested by Elke Eisenschmidt.
---
 Makefile.am                 |   2 +-
 vector_partition_chambers.c | 109 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 110 insertions(+), 1 deletion(-)
 create mode 100644 vector_partition_chambers.c

diff --git a/Makefile.am b/Makefile.am
index d3c77d6..76ad746 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -52,7 +52,7 @@ noinst_PROGRAMS = test testlib randomtest \
 		  polyhedron_sample 4coins lexmin @bv_barvinok_bound@ \
 		  @bv_cone_hilbert_basis@ cone_integer_hull \
 		  polytope_lattice_width polytope_minimize \
-		  polyhedron_integer_hull
+		  polyhedron_integer_hull vector_partition_chambers
 EXTRA_PROGRAMS = barvinok_bound test_bound cone_hilbert_basis
 pkginclude_HEADERS = \
     barvinok/NTL_QQ.h \
diff --git a/vector_partition_chambers.c b/vector_partition_chambers.c
new file mode 100644
index 0000000..f55bcd9
--- /dev/null
+++ b/vector_partition_chambers.c
@@ -0,0 +1,109 @@
+#include <barvinok/options.h>
+#include "argp.h"
+#include "progname.h"
+#include "param_util.h"
+
+/* This program computes the full-dimensional chambers of the vector
+ * partition function
+ *
+ * 			A \lambda = u
+ *
+ * The input is the matrix A in PolyLib notation.
+ * The output consists of the number of chambers, followed by
+ * a constraint description of each chamber in PolyLib notation.
+ *
+ * Example run:
+ *
+ *	$ cat elke
+ *	2 4
+ *	
+ *	1 1 1 1
+ *	0 1 2 3
+ *	
+ *	$ ./vector_partition_chambers < elke
+ *	3
+ *	
+ *	3 4
+ *	   1    1   -1    0
+ *	   1    0    1    0
+ *	   1    0    0    1
+ *	
+ *	3 4
+ *	   1   -1    1    0
+ *	   1    2   -1    0
+ *	   1    0    0    1
+ *	
+ *	3 4
+ *	   1    3   -1    0
+ *	   1   -2    1    0
+ *	   1    0    0    1
+ */
+
+static Polyhedron *partition2polyhedron(Matrix *A,
+					struct barvinok_options *options)
+{
+	int i;
+	unsigned nvar, nparam;
+	Matrix *M;
+	Polyhedron *P;
+
+	nvar = A->NbColumns;
+	nparam = A->NbRows;
+
+	M = Matrix_Alloc(nvar + nparam, 1 + nvar + nparam + 1);
+	assert(M);
+
+	for (i = 0; i < nparam; ++i) {
+		Vector_Copy(A->p[i], M->p[i] + 1, nvar);
+		value_set_si(M->p[i][1 + nvar + i], -1);
+	}
+	for (i = 0; i < nvar; ++i) {
+		value_set_si(M->p[nparam + i][0], 1);
+		value_set_si(M->p[nparam + i][1 + i], 1);
+	}
+
+	P = Constraints2Polyhedron(M, options->MaxRays);
+	Matrix_Free(M);
+
+	return P;
+}
+
+int main(int argc, char **argv)
+{
+	int nchamber;
+	unsigned nparam;
+	Matrix *A;
+	Polyhedron *P, *C;
+	Param_Polyhedron *PP;
+	Param_Domain *PD;
+	struct barvinok_options *options = barvinok_options_new_with_defaults();
+
+	set_program_name(argv[0]);
+	argp_parse(&barvinok_argp, argc, argv, 0, 0, options);
+
+	A = Matrix_Read();
+	assert(A);
+
+	nparam = A->NbRows;
+	C = Universe_Polyhedron(nparam);
+	P = partition2polyhedron(A, options);
+	Matrix_Free(A);
+
+	PP = Polyhedron2Param_Polyhedron(P, C, options);
+	Polyhedron_Free(P);
+	Polyhedron_Free(C);
+
+	nchamber = 0;
+	for (PD = PP->D; PD; PD = PD->next)
+		nchamber++;
+
+	printf("%d\n", nchamber);
+	for (PD = PP->D; PD; PD = PD->next) {
+		printf("\n");
+		Polyhedron_PrintConstraints(stdout, P_VALUE_FMT, PD->Domain);
+	}
+	Param_Polyhedron_Free(PP);
+
+	barvinok_options_free(options);
+	return 0;
+}
-- 
2.11.4.GIT