opt = nlopt.opt(nlopt.LD_MMA, 2)
opt.set_lower_bounds([-float('inf'), 0])
opt.set_min_objective(myfunc)
-opt.add_inequality_constraint(lambda x,grad: myconstraint(x,grad,2,0), 1e-8)
-opt.add_inequality_constraint(lambda x,grad: myconstraint(x,grad,-1,1), 1e-8)
+opt.add_inequality_constraint(lambda x, grad: myconstraint(x,grad, 2, 0), 1e-8)
+opt.add_inequality_constraint(lambda x, grad: myconstraint(x,grad, -1, 1), 1e-8)
opt.set_xtol_rel(1e-4)
x = opt.optimize([1.234, 5.678])
minf = opt.last_optimum_value()
-print('optimum at ', x[0],x[1])
+print('optimum at ', x[0], x[1])
print('minimum value = ', minf)
print('result code = ', opt.last_optimize_result())
+print('nevals = ', opt.get_numevals())