`GRADIENT`

variables ;

The GRADIENT statement defines the gradient vector which contains the first-order derivatives of the objective function with respect to . For more information, see the section Derivatives. To specify the values of nonzero derivatives, the variables specified in the GRADIENT statement must be defined on the left-hand side of algebraic expressions in programming statements. For example, consider the Rosenbrock function:

proc nlp tech=congra; min y; decvar x1 x2; gradient g1 g2; y1 = 10 * (x2 - x1 * x1); y2 = 1 - x1; y = .5 * (y1 * y1 + y2 * y2); g1 = -200 * x1 * (x2 - x1 * x1) - (1 - x1); g2 = 100 * (x2 - x1 * x1); run;