Hi all,

I read GAMS manual and find some unclear points.

I want to know what is the prod meaning in GAMS?

I know that it uses same sysntax as sum. But I am not sure what is it implying in economics.

Sum(j, x(j)) = x1+x2+x3+....xn

What prod(j, x(i, j)) is equivalent to?

Note that I see it uses with objective function.

obj.. UU =e= prod(i,x(i)**alpha(i));

Anyone, please help clarify me.

Thank you,

## GAMS sum and prod syntax_ what different?

### Re: GAMS sum and prod syntax_ what different?

Hi,

The product operation prod() represents the capital pi notation (see https://en.wikipedia.org/wiki/Multiplic ... i_notation).

This is similar to the sum operation sum() representing the captal sigma notation (https://en.wikipedia.org/wiki/Summation ... a_notation)

I hope this helps!

Fred

The product operation prod() represents the capital pi notation (see https://en.wikipedia.org/wiki/Multiplic ... i_notation).

This is similar to the sum operation sum() representing the captal sigma notation (https://en.wikipedia.org/wiki/Summation ... a_notation)

I hope this helps!

Fred

### Re: GAMS sum and prod syntax_ what different?

Hi Fred,

Many thanks for your reply.

I totally understand it now.

Best regards,

Many thanks for your reply.

I totally understand it now.

Best regards,