two conditional statement in a summation

GAMS
1

Hello
I want to add a conditional range summation equation, which has two conditional statements as mentioned below:

 Con23(bus).. 
sum (node $ ( conex(bus,node) and  (node>bus) ) ,lambda(bus,node)/branch(bus,node,'x') =e= 0 ;

There is no problem with the conditional sumation with first condition:

conex(bus,node)

but when I run the code with second one:

(node>bus)

, also with both of the conditions, I get this error (error code 148):
“dimension different: the symbol is referenced with more/less indices as declared.”
It is worth mentioning both “bus” and “node” sets are exactly equal, and I don’t know which indices are more/less.

2

what do you want to achieve with node > bus? Are these sets with numerical values?

You can consider using ord(node) > ord(bus)
or
node.val > bus.val

ord() gives position of the element .val understands that the set element is a number and uses that value.

Hope this helps.

  • Atharv
3

Thank you! The error is resolved