MINLPLib
A Library of Mixed-Integer and Continuous Nonlinear Programming Instances
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Instance ex6_1_4
| Formatsⓘ | ams gms mod nl osil py |
| Primal Bounds (infeas ≤ 1e-08)ⓘ | |
| 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 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;
Last updated: 2025-08-07 Git hash: e62cedfc

