GAMS World Forum

Hi, I am facing problem in making some constraints. At the end of this briefing you can find model. One can see eq_2 under mixer section, it is non-linear equation and I want to transform into linear equation because I am using MIP modelling. Eq_5 is basically energy balance equation of the below fo...

Thanks Renger for your response. I figured out that problem but now I have other problem. I want to transform below equation x = fc('1','H2O')/f('1') where x = composition of water in stream 1 fc('1','H2O') = component flow of water in stream 1 f('1') = total flow of stream 1 Also all x,fc and f are...

Hi Everyone! How to convert following non linear equation into linear z =x/y where z,x and y are continuous variables one way, I figured out from literature is below z*y = x (but this case is only true if z is constant, so this will not work for me) So, anybody please share the technique for reformu...

Hi all, Can anybody help me in finding the problem of following model binary variable b1 b2 ; positive variable p pressure 1 t temperature 1 t2 temperature 2 p2 pressure 2 ; variable obj ; equation a1 a2 a3 a4 a6 a7 ; a1.. t =e= 2*p ; a2.. p =l= 1000*b1 ; a3.. t2 =l= 8*p2 ; a4.. p2=e= 1000*b2; a6.. ...

Hi,
Could anyone tell what this error means, apparently syntax for calling algorithm seems correct and as follow
OPTION MINLP = LMLBOA ;

while error massage is attached in attachment, if more information is required to understand error please let me know.

Regards

Hi, The problem with the equation is You have to enter constant here. You can do this by summing or specifying certain for example 1. Load_balance.. X_g + X_pv -sum(t,L(t)) =E= 0 ; 2. Load_balance.. X_g + X_pv -L('t1') =E= 0 ; Otherwise GAMS dont know which element to select from the domain t until ...

Thank you very much for helping me.

Could you tell me how to make set controlled, As I am freshman, so mostly the error I receive is "uncontrolled set entered as a constant"

for example just see this syntax

material.. sum(pm(i,m),spltfrc(i,m)*f(i)) =e= sum(fm(i,m),f(i)) ;

I am finding error in objective function, I will highly appreciate, If somebody tell me reason of error. Below is the detail of model.. sets str process streams / 1*2/ comp compressor /1/ compon component feed /h2/ icomp(comp,str) inlet stream of compressor /1.1/ ocomp(comp,str) outlet stream of com...