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Hello

hope somebody can help me with my problem - any tiny help is highly appreciated! For days I have been trying to fix this, but I am not able to find a solution for it on my own (using the linked documents).

I am trying to optimize a scenario, where 3 suppliers are delivering 2 commodities to 3 markets. The costs for purchase (material prices + transportation) are subject to minimization. These are constrained by the capacity of the supplier and the demand of the markets.

I keep receiving an error message for the last 2 lines, where I want to define the constraints for the objective functions. According to the log file, there are no errors except for those 2 lines (Error 141 I will take care of afterwards).

54 cost … z =e= sum((i,j,k,t), f(i,j)*x(i,j,k,t)) + sum((i,j,k,t),x(i,j,k,t) *c(i,k,j));

55 supply(i) … sum((j,k,t), x(i,j,k,t)) =l= b(i,k,t) ;

**** $149,149

56 demand(j) … sum((i,k,t), x(i,j,k,t)) =g= a(j,t,k) ;

**** $149,149

57 Model Material_flow /all/ ;

58 Solve Material_flow using lp minimizing z ;

**** $257

59 Display x.l, x.m ;

**** $141

GAMS 24.1.3 r41464 Released Jul 26, 2013 WEX-VS8 x86/MS Windows 12/27/13 21:24:55 Page 2

G e n e r a l A l g e b r a i c M o d e l i n g S y s t e m

Error Messages

141 Symbol neither initialized nor assigned

A wild shot: You may have spurious commas in the explanatory

text of a declaration. Check symbol reference list.

149 Uncontrolled set entered as constant

257 Solve statement not checked because of previous errors

Many thanks for your feedback in advance!

Kind regards,

Alex

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Input.gms (2.82 KB)