GAMS World Forum

Hi,
I want to model this TTP. But i don't know, how to define the Set of Di? Have anyone of you some ideas how i can implement this?
My level of experience is very low

look up the section on the
"The conditional alternative: the tuple"

in the McCarl Guide at https://www.gams.com/mccarlGuide/gams_u ... e_2005.htm