Originally posted by: Lav4n

Hi all,

hope you can help me with this:

I have a decision expression, using the prev function on an index "period". In order to avoid an error I would like to constrain the calculation for all periods except the first one, where all values should be 0. So

dexpr float CostCalc [t in period] = CostPrameter[t] * (varX[t] - varX[prev(period,t)])

How could i prevend the error on t = 1 and condition it something like forall(t in period: t != 1)?

Thanks for your help!

Hi,

you could use the ternary operator.

Let me share a tiny example:

range period=1..5;
dvar int x[period];;

dexpr float CostCalc [t in period] = (t==1)?0:sum(i in 1..t-1)x[i];

regards

https://www.linkedin.com/pulse/what-optimization-how-can-help-you-do-more-less-zoo-buses-fleischer/

Originally posted by: Lav4n

Hi Alex,

thanks for your quick and kind answer!

That's exactly what I was searching for.

Really appreciate your support in this community through all the years!

Regards