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Instance ex6_1_4

Formats ams gms mod nl osil py
Primal Bounds (infeas ≤ 1e-08)
-0.29454129 p1 ( gdx sol )
(infeas: 1e-11)
Other points (infeas > 1e-08)  
Dual Bounds
-0.29454354 (ANTIGONE)
-0.29454129 (BARON)
-0.29454129 (COUENNE)
-0.29454135 (LINDO)
-0.29454129 (SCIP)
References Floudas, C A, Pardalos, Panos M, Adjiman, C S, Esposito, W R, Gumus, Zeynep H, Harding, S T, Klepeis, John L, Meyer, Clifford A, and Schweiger, C A, Handbook of Test Problems in Local and Global Optimization, Kluwer Academic Publishers, 1999.
McDonald, C M and Floudas, C A, Global Optimization for the Phase and Chemical Equilibrium Problem: Application to the NRTL Equation, Computers and Chemical Engineering, 19:11, 1995, 1111-1139.
Source Test Problem ex6.1.4 of Chapter 6 of Floudas e.a. handbook
Added to library 31 Jul 2001
Problem type NLP
#Variables 6
#Binary Variables 0
#Integer Variables 0
#Nonlinear Variables 6
#Nonlinear Binary Variables 0
#Nonlinear Integer Variables 0
Objective Sense min
Objective type nonlinear
Objective curvature indefinite
#Nonzeros in Objective 6
#Nonlinear Nonzeros in Objective 6
#Constraints 4
#Linear Constraints 1
#Quadratic Constraints 3
#Polynomial Constraints 0
#Signomial Constraints 0
#General Nonlinear Constraints 0
Operands in Gen. Nonlin. Functions log mul
Constraints curvature indefinite
#Nonzeros in Jacobian 15
#Nonlinear Nonzeros in Jacobian 12
#Nonzeros in (Upper-Left) Hessian of Lagrangian 21
#Nonzeros in Diagonal of Hessian of Lagrangian 3
#Blocks in Hessian of Lagrangian 1
Minimal blocksize in Hessian of Lagrangian 6
Maximal blocksize in Hessian of Lagrangian 6
Average blocksize in Hessian of Lagrangian 6.0
#Semicontinuities 0
#Nonlinear Semicontinuities 0
#SOS type 1 0
#SOS type 2 0
Minimal coefficient 3.4723e-02
Maximal coefficient 1.4481e+00
Infeasibility of initial point 1.11e-16
Sparsity Jacobian Sparsity of Objective Gradient and Jacobian
Sparsity Hessian of Lagrangian Sparsity of Hessian of Lagrangian

$offlisting
*  
*  Equation counts
*      Total        E        G        L        N        X        C        B
*          5        5        0        0        0        0        0        0
*  
*  Variable counts
*                   x        b        i      s1s      s2s       sc       si
*      Total     cont   binary  integer     sos1     sos2    scont     sint
*          7        7        0        0        0        0        0        0
*  FX      0
*  
*  Nonzero counts
*      Total    const       NL      DLL
*         22        4       18        0
*
*  Solve m using NLP minimizing objvar;


Variables  objvar,x2,x3,x4,x5,x6,x7;

Positive Variables  x5,x6,x7;

Equations  e1,e2,e3,e4,e5;


e1.. -((0.28809 + log(x2))*x2 + (-0.29158 + log(x3))*x3 + (0.59336 + log(x4))*
     x4 + x2*(1.44805026165593*x6 + 0.989428667054834*x7) + x3*(
     1.12676386427658*x5 + 1.00363012835441*x7) + x4*(0.0347225450624344*x5 + 
     0.82681418300153*x6)) + objvar =E= 0;

e2.. x5*(x2 + 0.145002897355373*x3 + 0.989528214945409*x4) - x2 =E= 0;

e3.. x6*(0.293701311601799*x2 + x3 + 0.646291923054068*x4) - x3 =E= 0;

e4.. x7*(0.619143628558899*x2 + 0.239837817616513*x3 + x4) - x4 =E= 0;

e5..    x2 + x3 + x4 =E= 1;

* set non-default bounds
x2.lo = 1E-6; x2.up = 1;
x3.lo = 1E-6; x3.up = 1;
x4.lo = 1E-6; x4.up = 1;

* set non-default levels
x2.l = 7E-5;
x3.l = 0.99686;
x4.l = 0.00307;
x5.l = 0.000474076675116379;
x6.l = 0.997993046160137;
x7.l = 0.0126755759820888;

Model m / all /;

m.limrow=0; m.limcol=0;
m.tolproj=0.0;

$if NOT '%gams.u1%' == '' $include '%gams.u1%'

$if not set NLP $set NLP NLP
Solve m using %NLP% minimizing objvar;


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