Originally posted by: HuuHuy

Dear

I have a problem with using CP ( Constrain programming) of Cplex version 12.6.2. Because stochastic time duration is not interger. Can you help me to declare duration time is float?

Thanks

Huu Huy

Originally posted by: GGR

Hi

For a CP  Optimizer model time as value of end-points of interval is integer. That is at model declaration, you first choose a time unit (for example 1 minute for a week/month schedule horizon) then you scale your data to fit the time unit definition.

The time unit should be the maximal duration so that two events cannot be distinguished in the physical system you are modeling. In CP Optimizer, the largest horizon is 2^53 -1 on a 64bit machine (about 10^16) which is large enough for any problem.

The fact the data are stochastic is not related to the time definition but to your model.

Once done you have to round your data to scale your data in time unit. Your will not loose any piece of relevant information.

If you are using a simulation to generate the time, the generator must follow the time unit principle to not over neither under determine dates and duration having a physical meaning.

Hope that helps