Use linear storage for dense matrices, for speed

library/gsl.pl

@@ -116,24 +116,6 @@
 	gsl_linalg_LU_det([ptr,sint], double)
 	]).
 
-mat_lup_det(M,Size,Det) :-
-	gsl_permutation_alloc(Size,P),
-	gsl_linalg_LU_decomp(M,P,Signum,_),
-	gsl_vector_alloc(Size,B),
-	(
-		between(1,Size,I),
-			I2 is I - 1,
-			V is float(I),
-			gsl_vector_set(B,I2,V),
-			fail; true
-	),
-	gsl_vector_alloc(Size,X),
-	gsl_linalg_LU_solve(M,P,B,X,_),
-	gsl_permutation_free(P),
-	gsl_vector_free(B),
-	gsl_vector_free(X),
-	gsl_linalg_LU_det(M,Signum,Det).
-
 vec_write(V,S) :- '$gsl_vector_write'(V,S).
 
 vec_read(V,S,Size1) :-

samples/test_matrix_det.pl

@@ -0,0 +1,27 @@
+:- use_module(library(gsl)).
+
+mat_lup_det(M,Size,Det) :-
+	gsl_permutation_alloc(Size,P),
+	gsl_linalg_LU_decomp(M,P,Signum,_),
+	gsl_vector_alloc(Size,B),
+	(
+		between(1,Size,I),
+			I2 is I - 1,
+			V is float(I),
+			gsl_vector_set(B,I2,V),
+			fail; true
+	),
+	gsl_vector_alloc(Size,X),
+	gsl_linalg_LU_solve(M,P,B,X,_),
+	gsl_permutation_free(P),
+	gsl_vector_free(B),
+	gsl_vector_free(X),
+	gsl_linalg_LU_det(M,Signum,Det).
+
+main :-
+	open('samples/test_matrix_det.mat',read,S),
+	mat_read(M,S,Rows,Cols),
+	mat_lup_det(M,Rows,Det),
+	gsl_matrix_free(M),
+	close(S),
+	write(Det), nl.