# hs109.mod	OOR2-MY-9-26
# Original AMPL coding by Elena Bobrovnikova (summer 1996 at Bell Labs).

# Ref.: W. Hock and K. Schittkowski, Test Examples for Nonlinear Programming
# Codes.  Lecture Notes in Economics and Mathematical Systems, v. 187,
# Springer-Verlag, New York, 1981, p. 118.

# Number of variables:  9
# Number of constraints:  26
# Objective separable
# Objective nonconvex
# Nonlinear constraints

param a;
param b1;
param b := sin(b1);
param c := cos(b1);

var x{1..9};

minimize Obj:
         3 * x[1] + 1E-6 * x[1]^3 + 2 * x[2] + .522074E-6 * x[2]^3;

s.t. C1:
     x[4] - x[3] + .55 >= 0;
s.t. C2:
     x[3] - x[4] + .55 >= 0;
s.t. C3:
     2250000 - x[1]^2 - x[8]^2 >= 0;
s.t. C4:
     2250000 - x[2]^2 - x[9]^2 >= 0;
s.t. C5:
     x[5] * x[6] * sin(-x[3] - .25) + x[5] * x[7] * sin(-x[4] - .25) +
     2 * b * x[5]^2 - a * x[1] + 400 * a = 0;
s.t. C6:
     x[5] * x[6] * sin(x[3] - .25) + x[6] * x[7] * sin(x[3] - x[4] - .25) +
     2 * b * x[6]^2 - a * x[2] + 400 * a = 0;
s.t. C7:
     x[5] * x[7] * sin(x[4] - .25) + x[6] * x[7] * sin(x[4] - x[3] - .25) +
     2 * b * x[7]^2 + 881.779 * a = 0;
s.t. C8:
     a * x[8] + x[5] * x[6] * cos(-x[3] - .25) +
     x[5] * x[7] * cos(-x[4] - .25) - 200 * a - 2 * c * x[5]^2 +
     .7533E-3 * a * x[5]^2 = 0;
s.t. C9:
     a * x[9] + x[5] * x[6] * cos(x[3] - .25) +
     x[6] * x[7] * cos(x[3] - x[4] - .25) - 2 * c * x[6]^2 +
     .7533E-3 * a * x[6]^2 - 200 * a = 0;
s.t. C10:
     x[5] * x[7] * cos(x[4] - .25) + x[6] * x[7] * cos(x[4] - x[3] - .25) -
     2 * c * x[7]^2 + 22.938 * a + .7533E-3 * a * x[7] ^2 = 0;
s.t. C11 {i in {1..2}}:
     x[i] >= 0;
s.t. C12 {i in {3..4}}:
     -.55 <= x[i] <= .55;
s.t. C13 {i in {5..7}}:
     196 <= x[i] <= 252;
s.t. C14 {i in {8..9}}:
     -400 <= x[i] <= 800;


data;

param a := 50.176;
param b1 := .25;

.