```
t(cn)$SUM((n,rgn), dat_n(n,cn,rgn,'Node','P')) = cn(cn); /* suppliers */
t_acc_np(t,n)$SUM((rgn), dat_n(n,t,rgn,'Node','P')) = 1;
```

As i as I understand it is a conditional statement that would be read as :

t(cn) should be equal to cn(cn) IF the SUM for all **n** and **rgn**, and im lost after that. Thanks in advance!!

For reference this is part of a gas market model at

https://www.ntnu.edu/iot/energy/energy-models-hub/ggm.

p/s this exact line of code is under the file “data>>in_market.gms”