Optmodel problem

qkaiwei — Wed, 21 Nov 2018 07:12:38 GMT

A question about constraint statement of optmodel procedure, sum of elements in array x must be less or equal to 100, and number of elements greater than 0 must be less or equal to 3, I don't know how to write this properly.

Thanks!

proc optmodel:

set<number> dates=1..10;

var x{dates} >=0 init 0;

......

con c1: sum{i in dates} x[i] <=100;

con c2: sum{i in dates} /*(x[i]>0)*/ <= 3;

quit;

Re: Optmodel problem

RobPratt — Wed, 21 Nov 2018 17:57:55 GMT

Introduce a binary variable y[i] that is 1 if x[i] > 0:

   var x{dates} >=0 init 0 <= 100;
   con c1: sum{i in dates} x[i] <=100;
   var y{dates} binary;
   con c2: sum{i in dates} y[i] <= 3;
   con c3 {i in dates}: x[i] <= x[i].ub * y[i];

topic Optmodel problem in Mathematical Optimization, Discrete-Event Simulation, and OR

Optmodel problem

Re: Optmodel problem