MINLPLib
A Library of Mixed-Integer and Continuous Nonlinear Programming Instances
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Instance hadamard_5
Maximize determinant of 5 times 5 binary matrix Let a(n) be the maximal determinant of a 0/1-matrix of size n by n. Hadamard proved that a(n) ≤ 2(-n) (n+1)((n+1)/2). A Hadamard matrix attains this bound. The Hadamard conjecture states that this is the case if and only if n+1 is 1 or 2 or a multiple of 4. The values of a(n) for small n are known. See the on-line encyclopedia of integer sequences for more information.
| Formatsⓘ | ams gms mod nl osil pip py |
| Primal Bounds (infeas ≤ 1e-08)ⓘ | |
| Other points (infeas > 1e-08)ⓘ | |
| Dual Boundsⓘ | 5.00000001 (ANTIGONE) 5.00000001 (BARON) 5.00000000 (COUENNE) 5.00000000 (LINDO) 5.00000000 (SCIP) 5.00000000 (SHOT) |
| Sourceⓘ | POLIP instance hadamard/hadamard_5 |
| Applicationⓘ | Linear Algebra |
| Added to libraryⓘ | 08 Dec 2018 |
| Problem typeⓘ | MBNLP |
| #Variablesⓘ | 26 |
| #Binary Variablesⓘ | 25 |
| #Integer Variablesⓘ | 0 |
| #Nonlinear Variablesⓘ | 25 |
| #Nonlinear Binary Variablesⓘ | 25 |
| #Nonlinear Integer Variablesⓘ | 0 |
| Objective Senseⓘ | max |
| Objective typeⓘ | linear |
| Objective curvatureⓘ | linear |
| #Nonzeros in Objectiveⓘ | 1 |
| #Nonlinear Nonzeros in Objectiveⓘ | 0 |
| #Constraintsⓘ | 1 |
| #Linear Constraintsⓘ | 0 |
| #Quadratic Constraintsⓘ | 0 |
| #Polynomial Constraintsⓘ | 1 |
| #Signomial Constraintsⓘ | 0 |
| #General Nonlinear Constraintsⓘ | 0 |
| Operands in Gen. Nonlin. Functionsⓘ | |
| Constraints curvatureⓘ | indefinite |
| #Nonzeros in Jacobianⓘ | 26 |
| #Nonlinear Nonzeros in Jacobianⓘ | 25 |
| #Nonzeros in (Upper-Left) Hessian of Lagrangianⓘ | 400 |
| #Nonzeros in Diagonal of Hessian of Lagrangianⓘ | 0 |
| #Blocks in Hessian of Lagrangianⓘ | 1 |
| Minimal blocksize in Hessian of Lagrangianⓘ | 25 |
| Maximal blocksize in Hessian of Lagrangianⓘ | 25 |
| Average blocksize in Hessian of Lagrangianⓘ | 25.0 |
| #Semicontinuitiesⓘ | 0 |
| #Nonlinear Semicontinuitiesⓘ | 0 |
| #SOS type 1ⓘ | 0 |
| #SOS type 2ⓘ | 0 |
| Minimal coefficientⓘ | 1.0000e+00 |
| Maximal coefficientⓘ | 1.0000e+00 |
| Infeasibility of initial pointⓘ | 0 |
| Sparsity Jacobianⓘ | ![]() |
| Sparsity Hessian of Lagrangianⓘ | ![]() |
$offlisting
*
* Equation counts
* Total E G L N X C B
* 1 0 1 0 0 0 0 0
*
* Variable counts
* x b i s1s s2s sc si
* Total cont binary integer sos1 sos2 scont sint
* 26 1 25 0 0 0 0 0
* FX 0
*
* Nonzero counts
* Total const NL DLL
* 26 1 25 0
*
* Solve m using MINLP maximizing objvar;
Variables b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17,b18,b19
,b20,b21,b22,b23,b24,b25,objvar;
Binary Variables b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17
,b18,b19,b20,b21,b22,b23,b24,b25;
Equations e1;
e1.. b1*b7*b13*b19*b25 - b1*b7*b13*b20*b24 + b1*b7*b15*b18*b24 - b1*b10*b12*b18
*b24 + b5*b6*b12*b18*b24 - b5*b6*b12*b19*b23 + b1*b10*b12*b19*b23 - b1*b7*
b15*b19*b23 + b1*b7*b14*b20*b23 - b1*b7*b14*b18*b25 + b1*b9*b12*b18*b25 -
b1*b9*b12*b20*b23 + b1*b9*b15*b17*b23 - b1*b10*b14*b17*b23 + b5*b6*b14*b17
*b23 - b5*b9*b11*b17*b23 + b4*b10*b11*b17*b23 - b4*b6*b15*b17*b23 + b4*b6*
b12*b20*b23 - b4*b6*b12*b18*b25 + b4*b6*b13*b17*b25 - b4*b6*b13*b20*b22 +
b4*b6*b15*b18*b22 - b4*b10*b11*b18*b22 + b5*b9*b11*b18*b22 - b5*b6*b14*b18
*b22 + b1*b10*b14*b18*b22 - b1*b9*b15*b18*b22 + b1*b9*b13*b20*b22 - b1*b9*
b13*b17*b25 + b1*b8*b14*b17*b25 - b1*b8*b14*b20*b22 + b1*b8*b15*b19*b22 -
b1*b10*b13*b19*b22 + b5*b6*b13*b19*b22 - b5*b6*b13*b17*b24 + b1*b10*b13*
b17*b24 - b1*b8*b15*b17*b24 + b1*b8*b12*b20*b24 - b1*b8*b12*b19*b25 + b3*
b6*b12*b19*b25 - b3*b6*b12*b20*b24 + b3*b6*b15*b17*b24 - b3*b10*b11*b17*
b24 + b5*b8*b11*b17*b24 - b5*b8*b11*b19*b22 + b3*b10*b11*b19*b22 - b3*b6*
b15*b19*b22 + b3*b6*b14*b20*b22 - b3*b6*b14*b17*b25 + b3*b9*b11*b17*b25 -
b3*b9*b11*b20*b22 + b3*b9*b15*b16*b22 - b3*b10*b14*b16*b22 + b5*b8*b14*b16
*b22 - b5*b9*b13*b16*b22 + b4*b10*b13*b16*b22 - b4*b8*b15*b16*b22 + b4*b8*
b11*b20*b22 - b4*b8*b11*b17*b25 + b4*b8*b12*b16*b25 - b4*b8*b12*b20*b21 +
b4*b8*b15*b17*b21 - b4*b10*b13*b17*b21 + b5*b9*b13*b17*b21 - b5*b8*b14*b17
*b21 + b3*b10*b14*b17*b21 - b3*b9*b15*b17*b21 + b3*b9*b12*b20*b21 - b3*b9*
b12*b16*b25 + b3*b7*b14*b16*b25 - b3*b7*b14*b20*b21 + b3*b7*b15*b19*b21 -
b3*b10*b12*b19*b21 + b5*b8*b12*b19*b21 - b5*b8*b12*b16*b24 + b3*b10*b12*
b16*b24 - b3*b7*b15*b16*b24 + b3*b7*b11*b20*b24 - b3*b7*b11*b19*b25 + b2*
b8*b11*b19*b25 - b2*b8*b11*b20*b24 + b2*b8*b15*b16*b24 - b2*b10*b13*b16*
b24 + b5*b7*b13*b16*b24 - b5*b7*b13*b19*b21 + b2*b10*b13*b19*b21 - b2*b8*
b15*b19*b21 + b2*b8*b14*b20*b21 - b2*b8*b14*b16*b25 + b2*b9*b13*b16*b25 -
b2*b9*b13*b20*b21 + b2*b9*b15*b18*b21 - b2*b10*b14*b18*b21 + b5*b7*b14*b18
*b21 - b5*b9*b12*b18*b21 + b4*b10*b12*b18*b21 - b4*b7*b15*b18*b21 + b4*b7*
b13*b20*b21 - b4*b7*b13*b16*b25 + b4*b7*b11*b18*b25 - b4*b7*b11*b20*b23 +
b4*b7*b15*b16*b23 - b4*b10*b12*b16*b23 + b5*b9*b12*b16*b23 - b5*b7*b14*b16
*b23 + b2*b10*b14*b16*b23 - b2*b9*b15*b16*b23 + b2*b9*b11*b20*b23 - b2*b9*
b11*b18*b25 + b2*b6*b14*b18*b25 - b2*b6*b14*b20*b23 + b2*b6*b15*b19*b23 -
b2*b10*b11*b19*b23 + b5*b7*b11*b19*b23 - b5*b7*b11*b18*b24 + b2*b10*b11*
b18*b24 - b2*b6*b15*b18*b24 + b2*b6*b13*b20*b24 - b2*b6*b13*b19*b25
- objvar =G= 0;
Model m / all /;
m.limrow=0; m.limcol=0;
m.tolproj=0.0;
$if NOT '%gams.u1%' == '' $include '%gams.u1%'
$if not set MINLP $set MINLP MINLP
Solve m using %MINLP% maximizing objvar;
Last updated: 2025-08-07 Git hash: e62cedfc

