- : one of the equation in the system has not a type 0, -1, -2, 2, 10 or 1 (i.e. it's not an equation or an optimum function, neither inequality or an inequality )
- : there is no optimum function i.e. no equation has type 2 or -2 or 10
- : there is more than one optimum function i.e. more than one equation has type 2 or -2 or 10
- : the last function is not the one to be minimized or maximized

Jean-Pierre Merlet 2012-12-20