MINLPLib
A Library of Mixed-Integer and Continuous Nonlinear Programming Instances
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Instance st_e41
| Formatsⓘ | ams gms mod nl osil py |
| Primal Bounds (infeas ≤ 1e-08)ⓘ | |
| Other points (infeas > 1e-08)ⓘ | |
| Dual Boundsⓘ | 641.82356170 (ANTIGONE) 641.82356100 (BARON) 641.82315590 (COUENNE) 641.82345950 (LINDO) 641.82355980 (SCIP) |
| Referencesⓘ | Tawarmalani, M and Sahinidis, N V, Convexification and Global Optimization in Continuous and Mixed-Integer Nonlinear Programming: Theory, Algorithms, Software, and Applications, Kluwer, 2002. Kim, Y S, Problems in reliability, 1998. Personal Communication. |
| Sourceⓘ | BARON book instance misc/e41 |
| Added to libraryⓘ | 03 Sep 2002 |
| Problem typeⓘ | NLP |
| #Variablesⓘ | 4 |
| #Binary Variablesⓘ | 0 |
| #Integer Variablesⓘ | 0 |
| #Nonlinear Variablesⓘ | 4 |
| #Nonlinear Binary Variablesⓘ | 0 |
| #Nonlinear Integer Variablesⓘ | 0 |
| Objective Senseⓘ | min |
| Objective typeⓘ | signomial |
| Objective curvatureⓘ | concave |
| #Nonzeros in Objectiveⓘ | 4 |
| #Nonlinear Nonzeros in Objectiveⓘ | 4 |
| #Constraintsⓘ | 2 |
| #Linear Constraintsⓘ | 0 |
| #Quadratic Constraintsⓘ | 0 |
| #Polynomial Constraintsⓘ | 2 |
| #Signomial Constraintsⓘ | 0 |
| #General Nonlinear Constraintsⓘ | 0 |
| Operands in Gen. Nonlin. Functionsⓘ | |
| Constraints curvatureⓘ | indefinite |
| #Nonzeros in Jacobianⓘ | 8 |
| #Nonlinear Nonzeros in Jacobianⓘ | 8 |
| #Nonzeros in (Upper-Left) Hessian of Lagrangianⓘ | 16 |
| #Nonzeros in Diagonal of Hessian of Lagrangianⓘ | 4 |
| #Blocks in Hessian of Lagrangianⓘ | 1 |
| Minimal blocksize in Hessian of Lagrangianⓘ | 4 |
| Maximal blocksize in Hessian of Lagrangianⓘ | 4 |
| Average blocksize in Hessian of Lagrangianⓘ | 4.0 |
| #Semicontinuitiesⓘ | 0 |
| #Nonlinear Semicontinuitiesⓘ | 0 |
| #SOS type 1ⓘ | 0 |
| #SOS type 2ⓘ | 0 |
| Minimal coefficientⓘ | 6.0000e-01 |
| Maximal coefficientⓘ | 3.0000e+02 |
| Infeasibility of initial pointⓘ | 0.1266 |
| Sparsity Jacobianⓘ | ![]() |
| Sparsity Hessian of Lagrangianⓘ | ![]() |
$offlisting
*
* Equation counts
* Total E G L N X C B
* 3 1 0 2 0 0 0 0
*
* Variable counts
* x b i s1s s2s sc si
* Total cont binary integer sos1 sos2 scont sint
* 5 5 0 0 0 0 0 0
* FX 0
*
* Nonzero counts
* Total const NL DLL
* 13 1 12 0
*
* Solve m using NLP minimizing objvar;
Variables x1,x2,x3,x4,objvar;
Equations e1,e2,e3;
e1.. -(-sqr(1 - x1)*x3*sqr(1 - x4) - sqr(1 - (1 - (1 - x1)*(1 - x4))*x2)*(1 -
x3)) =L= 0.1;
e2.. (-sqr(1 - x1)*x3*sqr(1 - x4)) - sqr(1 - (1 - (1 - x1)*(1 - x4))*x2)*(1 -
x3) =L= 0;
e3.. -(200*x1**0.6 + 200*x2**0.6 + 200*x3**0.6 + 300*x4**0.6) + objvar =E= 0;
* set non-default bounds
x1.lo = 0.5; x1.up = 1;
x2.lo = 0.5; x2.up = 1;
x3.lo = 0.5; x3.up = 1;
x4.lo = 0.5; x4.up = 1;
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

