[gnumeric] Solver: simplify.

[Morten Welinder <mortenw src gnome org>]

commit e5f060a934264010035505400deb86bafedcc381
Author: Morten Welinder <terra gnome org>
Date:   Sat Jun 2 20:51:17 2018 -0400

    Solver: simplify.

 src/tools/gnm-solver.c | 89 +++++++++++++++++++++++---------------------------
 1 file changed, 40 insertions(+), 49 deletions(-)
---
diff --git a/src/tools/gnm-solver.c b/src/tools/gnm-solver.c
index 16f4712e6..cca96d5cb 100644
--- a/src/tools/gnm-solver.c
+++ b/src/tools/gnm-solver.c
@@ -928,14 +928,14 @@ gnm_solver_dispose (GObject *obj)
                gnm_solver_update_derived (sol);
        }
 
+       sol->gradient_status = 0;
        if (sol->gradient) {
-               sol->gradient_status = 0;
                g_ptr_array_unref (sol->gradient);
                sol->gradient = NULL;
        }
 
+       sol->hessian_status = 0;
        if (sol->hessian) {
-               sol->hessian_status = 0;
                g_ptr_array_unref (sol->hessian);
                sol->hessian = NULL;
        }
@@ -1267,6 +1267,17 @@ gnm_solver_has_solution (GnmSolver *solver)
        }
 }
 
+static gnm_float
+get_cell_value (GnmCell *cell)
+{
+       GnmValue const *v;
+       gnm_cell_eval (cell);
+       v = cell->value;
+       return VALUE_IS_NUMBER (v) || VALUE_IS_EMPTY (v)
+               ? value_get_as_float (v)
+               : gnm_nan;
+}
+
 gboolean
 gnm_solver_check_constraints (GnmSolver *solver)
 {
@@ -1281,10 +1292,10 @@ gnm_solver_check_constraints (GnmSolver *solver)
 
                for (ui = 0; ui < solver->input_cells->len; ui++) {
                        GnmCell *cell = g_ptr_array_index (solver->input_cells, ui);
-                       gnm_float val;
+                       gnm_float val = get_cell_value (cell);
 
-                       gnm_cell_eval (cell);
-                       val = value_get_as_float (cell->value);
+                       if (!gnm_finite (val))
+                               break;
                        if (sp->options.assume_non_negative && val < 0)
                                break;
                        if (sp->options.assume_discrete &&
@@ -1308,14 +1319,10 @@ gnm_solver_check_constraints (GnmSolver *solver)
                                                     &lhs, &cl,
                                                     &rhs, &cr);
                     i++) {
-                       if (lhs) {
-                               gnm_cell_eval (lhs);
-                               cl = value_get_as_float (lhs->value);
-                       }
-                       if (rhs) {
-                               gnm_cell_eval (rhs);
-                               cr = value_get_as_float (rhs->value);
-                       }
+                       if (lhs)
+                               cl = get_cell_value (lhs);
+                       if (rhs)
+                               cr = get_cell_value (rhs);
 
                        switch (c->type) {
                        case GNM_SOLVER_INTEGER:
@@ -1452,15 +1459,16 @@ cell_in_cr (GnmSolver *sol, GnmCell const *cell, gboolean follow)
 static gboolean
 cell_is_constant (GnmCell *cell, gnm_float *pc)
 {
-       if (!cell)
+       if (!cell) {
+               *pc = 0;
                return TRUE;
+       }
 
        if (cell->base.texpr)
                return FALSE;
 
-       gnm_cell_eval (cell);
-       *pc = value_get_as_float (cell->value);
-       return TRUE;
+       *pc = get_cell_value (cell);
+       return gnm_finite (*pc);
 }
 
 #define SET_LOWER(l_)                                          \
@@ -1761,14 +1769,10 @@ gnm_solver_create_program_report (GnmSolver *solver, const char *name)
                        dao_set_cell (dao, 1, R, ctxt);
                        g_free (ctxt);
 
-                       if (lhs) {
-                               gnm_cell_eval (lhs);
-                               cl = value_get_as_float (lhs->value);
-                       }
-                       if (rhs) {
-                               gnm_cell_eval (rhs);
-                               cr = value_get_as_float (rhs->value);
-                       }
+                       if (lhs)
+                               cl = get_cell_value (lhs);
+                       if (rhs)
+                               cr = get_cell_value (rhs);
 
                        switch (c->type) {
                        case GNM_SOLVER_INTEGER: {
@@ -1910,14 +1914,10 @@ gnm_solver_create_sensitivity_report (GnmSolver *solver, const char *name)
                        dao_set_cell (dao, 1, R, ctxt);
                        g_free (ctxt);
 
-                       if (lhs) {
-                               gnm_cell_eval (lhs);
-                               cl = value_get_as_float (lhs->value);
-                       }
-                       if (rhs) {
-                               gnm_cell_eval (rhs);
-                               cr = value_get_as_float (rhs->value);
-                       }
+                       if (lhs)
+                               cl = get_cell_value (lhs);
+                       if (rhs)
+                               cr = get_cell_value (rhs);
 
                        add_value_or_special (dao, 2, R, sols->constraints[cidx].shadow_price);
                        add_value_or_special (dao, 3, R, cl);
@@ -1969,16 +1969,8 @@ gnm_solver_create_report (GnmSolver *solver, const char *base)
 gnm_float
 gnm_solver_get_target_value (GnmSolver *solver)
 {
-       GnmValue const *v;
-
-       gnm_cell_eval (solver->target);
-       v = solver->target->value;
-
-       if (VALUE_IS_NUMBER (v) || VALUE_IS_EMPTY (v)) {
-               gnm_float y = value_get_as_float (v);
-               return solver->flip_sign ? 0 - y : y;
-       } else
-               return gnm_nan;
+       gnm_float y = get_cell_value (solver->target);
+       return solver->flip_sign ? 0 - y : y;
 }
 
 void
@@ -2070,6 +2062,8 @@ gnm_solver_has_analytic_gradient (GnmSolver *sol)
                        else {
                                if (gnm_solver_debug ())
                                        g_printerr ("Unable to compute analytic gradient\n");
+                               g_ptr_array_unref (sol->gradient);
+                               sol->gradient = NULL;
                                sol->gradient_status++;
                                break;
                        }
@@ -2513,8 +2507,7 @@ gnm_solver_get_lp_coeffs (GnmSolver *sol, GnmCell *ycell,
        gnm_float y0;
 
        gnm_solver_set_vars (sol, x1);
-       gnm_cell_eval (ycell);
-       y0 = VALUE_IS_NUMBER (ycell->value) ? value_get_as_float (ycell->value) : gnm_nan;
+       y0 = get_cell_value (ycell);
        if (!gnm_finite (y0))
                goto fail_calc;
 
@@ -2527,8 +2520,7 @@ gnm_solver_get_lp_coeffs (GnmSolver *sol, GnmCell *ycell,
                }
 
                gnm_solver_set_var (sol, ui, x2[ui]);
-               gnm_cell_eval (ycell);
-               y1 = VALUE_IS_NUMBER (ycell->value) ? value_get_as_float (ycell->value) : gnm_nan;
+               y1 = get_cell_value (ycell);
 
                dy = y1 - y0;
                res[ui] = dy / dx;
@@ -2541,8 +2533,7 @@ gnm_solver_get_lp_coeffs (GnmSolver *sol, GnmCell *ycell,
                        x01 = (x1[ui] + x2[ui]) / 2;
                        if (sol->discrete[ui]) x01 = gnm_floor (x01);
                        gnm_solver_set_var (sol, ui, x01);
-                       gnm_cell_eval (ycell);
-                       y01 = VALUE_IS_NUMBER (ycell->value) ? value_get_as_float (ycell->value) : gnm_nan;
+                       y01 = get_cell_value (ycell);
                        if (!gnm_finite (y01))
                                goto fail_calc;