parameter with undefined set

GAMS
1

Hi all,

I got a problem with a parameter with the undefined set. For example record(*).

I defined a parameter record() and have data input using the flexible name of the index. i.e. record(‘anything I want’)=number for hundreds of them; Now I would like to process this parameter with simple operations like record2()=record(*) +2; But has the following errors. Not sure using the * is the right way to do that. Can anybody share some insight as to how to conduct the mathematical operations using parameters with the undefined set?

Thanks

record2()=record();
**** $145 $145,148,8,119
**** 8 ‘)’ expected
**** 119 Number (primary) expected
**** 145 Set identifier or quoted element expected
**** 148 Dimension different - The symbol is referenced with more/less
**** indices as declared

2

Using universe as a domain is handy but dangerous. Nothing wrong with making a set of “anything you want” elements. If it has to be universe, you can use “*” in assignment statements via the alias statement:

parameter r(*), r2(*);
r('abc') = pi;
alias (*,uni);
r2(uni) = 2*r(uni);

-Michael

3

Thank you Michael!