Water Resources Research Report - Western Engineering ...

infeasible solution. Careful selection of the penalty parameters is required for the proper
convergence to a feasible optimal solution.
The main C program has many user-defined functions. The user needs to enter objective
function and constraints in the user-defined function evaluate( ). The program code is
commented, so the user needs to follow the comments to enter the number of constraints,
ncons (in this example, ncons = 2), objective function, constraints (if any) and the penalty
coefficient for each constraint (if any), at the appropriate places. The “evaluate( )”
function for the example problem is displayed below:
double evaluate(double *x)
{
int ncons, i;
double *val, *penal, temp;
long double value=0;
feval++;
/* DO NOT CHANGE ANYTHING ABOVE */
/* Enter the Number of Constraints to the variable ncons*/
ncons = 2;
/*------------------------------------------------------*/
val = (double *)malloc(sizeof(double)*ncons);
penal = (double *)malloc(sizeof(double)*ncons);
penal[0]=1;
/*----------------------CODE YOUR OBJECTIVE FUNCTIONS HERE------------*/
/*All functions must be of minimization type*/
/*============Start Coding Your Objective Function=============*/
val[0] = (x[0]*x[0]+x[1]-11)*(x[0]*x[0]+x[1]-11) +
(x[0]+x[1]*x[1]-7)*(x[0]+x[1]*x[1]-7);
/*========END YOUR CODING UPTO THIS POINT============*/
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