void lmm_elem_set_value(lmm_system_t sys, lmm_constraint_t cnst,
lmm_variable_t var, double value);
-lmm_constraint_t) lmm_get_cnst_from_var(lmm_system_t sys,
+lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t sys,
lmm_variable_t var, int num);
int lmm_get_number_of_cnst_from_var(lmm_system_t sys, lmm_variable_t var);
lmm_variable_t lmm_get_var_from_cnst(lmm_system_t sys,