Re: [Help-glpk] Maximum number of integer variables -- is 1.75 million sufficient?

[Nigel Galloway]

I know I can probably produce a better analysis of the uniformity of glpk's 
random number generator with a sample size smaller than 1.75 million integers, 
but what would be the point of that?

More interestingly is why does mathprog require a 1000 bytes per integer?


/*Arithmetic Mean of a large number of random Integers
   between 1 and 9 inclusive should be 5. The sum over each
   (random Integer - 5) should be 0, is it for glpk's psudo random
   generator?
  - or - another excuse to solve a very large constraint matrix
         over 1.75 million integers with 2GB of memory.
  address@hidden
  July 18th., 2008.
*/

param e := 1750000;
param Sample {x in 1..e} := floor(Uniform(1,10)),integer;
var Mean := 5;
var E {x in 1..e},integer;

/* Mean + variance[n] = Sample[n] */
variances{z in 1..e}: Mean + E[z] = Sample[z];

solve;

printf "%d\n", sum{x in 1..e} E[x];

end;


C:\Users\Nigel\glpk>glpsol --math Mean\randomtest.mathprog
Reading model section from Mean\randomtest.mathprog...
20 lines were read
Generating variances...
Model has been successfully generated
glp_simplex: original LP has 1500000 rows, 1500000 columns, 1500000 non-zeros
Objective value = 0
OPTIMAL SOLUTION FOUND BY LP PRESOLVER
Integer optimization begins...
+     0: mip =     not found yet >=              -inf        (1; 0)
+     0: >>>>>   0.000000000e+00 >=   0.000000000e+00   0.0% (1; 0)
+     0: mip =   0.000000000e+00 >=     tree is empty   0.0% (0; 1)
INTEGER OPTIMAL SOLUTION FOUND
Time used:   8.0 secs
Memory used: 1511.3 Mb (1584708640 bytes)
-4730
Model has been successfully processed

C:\Users\Nigel\glpk>glpsol --math Mean\randomtest.mathprog
Reading model section from Mean\randomtest.mathprog...
20 lines were read
Generating variances...
Model has been successfully generated
glp_simplex: original LP has 1750000 rows, 1750000 columns, 1750000 non-zeros
Objective value = 0
OPTIMAL SOLUTION FOUND BY LP PRESOLVER
Integer optimization begins...
+     0: mip =     not found yet >=              -inf        (1; 0)
+     0: >>>>>   0.000000000e+00 >=   0.000000000e+00   0.0% (1; 0)
+     0: mip =   0.000000000e+00 >=     tree is empty   0.0% (0; 1)
INTEGER OPTIMAL SOLUTION FOUND
Time used:   14.0 secs
Memory used: 1778.8 Mb (1865218544 bytes)
-5814
Model has been successfully processed

C:\Users\Nigel\glpk>glpsol --math Mean\randomtest.mathprog
Reading model section from Mean\randomtest.mathprog...
20 lines were read
Generating variances...
Model has been successfully generated
glp_simplex: original LP has 2000000 rows, 2000000 columns, 2000000 non-zeros
Objective value = 0
OPTIMAL SOLUTION FOUND BY LP PRESOLVER
Integer optimization begins...
+     0: mip =     not found yet >=              -inf        (1; 0)
xmalloc: no memory available

Abnormal program termination



> ----- Original Message -----
> From: mbanco <address@hidden>
> To: address@hidden
> Subject: [Help-glpk] Maximum number of integer variables
> Date: Thu, 17 Jul 2008 03:53:12 -0700 (PDT)
> 
> 
> 
> Does anyone know how many integers variables can handle the glpk 4.29?
> --
> View this message in context: 
> http://www.nabble.com/Maximum-number-of-integer-variables-tp18505960p18505960.html
> Sent from the Gnu - GLPK - Help mailing list archive at Nabble.com.
> 
> 
> 
> _______________________________________________
> Help-glpk mailing list
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> http://lists.gnu.org/mailman/listinfo/help-glpk

>


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