static void
set_vector (GnmNlsolve *nl, const gnm_float *xs)
{
gnm_solver_set_vars (nl->sol, xs);
}
static gboolean
glpk_affine_func (GString *dst, GnmCell *target, GnmSubSolver *ssol,
gnm_float const *x1, gnm_float const *x2,
gboolean zero_too,
gnm_float cst, GError **err)
{
GnmSolver *sol = GNM_SOLVER (ssol);
unsigned ui;
gboolean any = FALSE;
gnm_float y;
gboolean ok = TRUE;
GPtrArray *input_cells = sol->input_cells;
gnm_float *cs;
if (!target) {
gnm_string_add_number (dst, cst);
return TRUE;
}
gnm_solver_set_vars (sol, x1);
gnm_cell_eval (target);
y = cst + value_get_as_float (target->value);
cs = gnm_solver_get_lp_coeffs (sol, target, x1, x2, err);
if (!cs)
goto fail;
/* Adjust constant for choice of x1. */
for (ui = 0; ui < input_cells->len; ui++)
y -= x1[ui] * cs[ui];
for (ui = 0; ui < input_cells->len; ui++) {
GnmCell *cell = g_ptr_array_index (input_cells, ui);
gnm_float x = cs[ui];
if (x == 0 && !zero_too)
continue;
if (any) {
if (x < 0)
g_string_append (dst, " - ");
else
g_string_append (dst, " + ");
} else {
if (x < 0)
g_string_append_c (dst, '-');
}
x = gnm_abs (x);
if (x != 1) {
gnm_string_add_number (dst, x);
g_string_append_c (dst, ' ');
}
g_string_append (dst, glpk_var_name (ssol, cell));
any = TRUE;
}
if (!any || y) {
if (any) {
g_string_append_c (dst, ' ');
if (y > 0)
g_string_append_c (dst, '+');
}
gnm_string_add_number (dst, y);
}
fail:
g_free (cs);
return ok;
}