Originally posted by: february_Birthed

Hello ,
I am trying to write cp code for golomb ruler problem
but OPL shows error on this line :

in the following code I want to calculate the value x[i] - x[j] and put the value in array d that has n*n(n+1)/2 elements but it shows error

forall(i,j in 1..n: j>i)dk in ftoi(n*(n+1))/2==abs(x[i] - x[j]) ;
#DecisionOptimization
#OPLusingCPLEXOptimizer

Originally posted by: SystemAdmin

I am not able to completely understand your indexes because you mention that d has n*n(n+1)/2 elements, but in your forall statement d's index k, seems to be iterating over n*(n+1)/2 elements. In any case, you may want to use a syntax like the following and see if that works:

forall(i,j in 1..n,k in 1..ftoi(n*(n+1)/2):j>i)
  d[k]==abs(x[i] - x[j]);

If you are still having problems, please post your code within {code} tags so that the formatting is maintained.
#DecisionOptimization
#OPLusingCPLEXOptimizer