[gnumeric] LINSOLVE: handle more than one column on right-hand side.

[Morten Welinder <mortenw src gnome org>]

commit 3ae273bc2695749305b8436766c3c1fe9d24d593
Author: Morten Welinder <terra gnome org>
Date:   Tue Jan 22 12:48:48 2013 -0500

    LINSOLVE: handle more than one column on right-hand side.

 plugins/fn-math/functions.c |   22 +++++++---------------
 src/regression.h            |    2 ++
 2 files changed, 9 insertions(+), 15 deletions(-)
---
diff --git a/plugins/fn-math/functions.c b/plugins/fn-math/functions.c
index 207e603..205eb3c 100644
--- a/plugins/fn-math/functions.c
+++ b/plugins/fn-math/functions.c
@@ -2779,11 +2779,11 @@ out:
 
 static GnmFuncHelp const help_linsolve[] = {
         { GNM_FUNC_HELP_NAME, F_("LINSOLVE:solve linear equation")},
-        { GNM_FUNC_HELP_ARG, F_("mat:a matrix")},
-        { GNM_FUNC_HELP_ARG, F_("col:a column")},
+        { GNM_FUNC_HELP_ARG, F_("A:a matrix")},
+        { GNM_FUNC_HELP_ARG, F_("B:a matrix")},
 	{ GNM_FUNC_HELP_DESCRIPTION,
-	  F_("Solves the equation @{mat}*x= {col} and returns x.") },
-	{ GNM_FUNC_HELP_NOTE, F_("If the matrix is singular, #VALUE! is returned.") },
+	  F_("Solves the equation @{A}*X= {B} and returns X.") },
+	{ GNM_FUNC_HELP_NOTE, F_("If the matrix @{A} is singular, #VALUE! is returned.") },
 	{ GNM_FUNC_HELP_SEEALSO, "MINVERSE"},
         { GNM_FUNC_HELP_END}
 };
@@ -2794,9 +2794,7 @@ gnumeric_linsolve (GnmFuncEvalInfo *ei, GnmValue const * const *argv)
 {
 	GnmMatrix *A = NULL;
 	GnmMatrix *B = NULL;
-	gnm_float *x;
 	GnmValue *res = NULL;
-	int i;
 	GORegressionResult regres;
 
 	A = gnm_matrix_from_value (argv[0], &res, ei->pos);
@@ -2806,16 +2804,12 @@ gnumeric_linsolve (GnmFuncEvalInfo *ei, GnmValue const * const *argv)
 	if (!B) goto out;
 
 	if (A->cols != A->rows || gnm_matrix_is_empty (A) ||
-	    B->cols != 1 || B->rows != A->rows || gnm_matrix_is_empty (B)) {
+	    B->rows != A->rows || gnm_matrix_is_empty (B)) {
 		res = value_new_error_VALUE (ei->pos);
 		goto out;
 	}
 
-	x = g_new (gnm_float, B->rows);
-	for (i = 0; i < B->rows; i++)
-		x[i] = B->data[i][0];
-
-	regres = gnm_linear_solve (A->data, x, A->rows, x);
+	regres = gnm_linear_solve_multiple (A->data, B->data, A->rows, B->cols);
 
 	if (regres != GO_REG_ok && regres != GO_REG_near_singular_good) {
 		res = value_new_error_NUM (ei->pos);
@@ -2827,12 +2821,10 @@ gnumeric_linsolve (GnmFuncEvalInfo *ei, GnmValue const * const *argv)
 			res->v_array.vals[c] = g_new (GnmValue *, B->rows);
 			for (r = 0; r < B->rows; r++)
 				res->v_array.vals[c][r] =
-					value_new_float (x[r]);
+					value_new_float (B->data[r][c]);
 		}
 	}
 
-	g_free (x);
-
 out:
 	if (A) gnm_matrix_free (A);
 	if (B) gnm_matrix_free (B);
diff --git a/src/regression.h b/src/regression.h
index d9a0c7b..fa365fa 100644
--- a/src/regression.h
+++ b/src/regression.h
@@ -21,6 +21,7 @@ G_BEGIN_DECLS
 #	define gnm_matrix_invert go_matrix_invertl
 #	define gnm_matrix_determinant go_matrix_determinantl
 #	define gnm_linear_solve go_linear_solvel
+#	define gnm_linear_solve_multiple go_linear_solve_multiplel
 #else
 #	define gnm_regression_stat_t go_regression_stat_t
 #	define gnm_regression_stat_new go_regression_stat_new
@@ -35,6 +36,7 @@ G_BEGIN_DECLS
 #	define gnm_matrix_invert go_matrix_invert
 #	define gnm_matrix_determinant go_matrix_determinant
 #	define gnm_linear_solve go_linear_solve
+#	define gnm_linear_solve_multiple go_linear_solve_multiple
 #endif
 
 G_END_DECLS