Useful commands for developing the course project

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*= add a comment $... = execute a command; $title = title of the code $ontext/$offtext = add a comment without using * $include + name of the file.gms = I can add subprograms by calling them from outside of my code you can avoid listing n elements by using the compact notation w/ the * ; Display = display the specified variables on the output report; use it frequently Sum(sets, variables(sets)) SET = I define the domain of a parameter or variable Identify the domain + ‘name of the domain’ + / elements of the domain / ; \ I can avoid to express every element if these are subsequently by using *; I may also want to define subsets, so I define 1 set dependent from the other like a variable with parenthesis; mapping gives me the possibility to relate a set with another and help me to visualize the results in a logical table (I have to use a point between the elements of the different sets); \ Ord (set) = ; Card (set) = number of elements in a set; ALIAS = give different name to previously defined sets; Managing Data: PARAMETER = define a parameter called x that has a value for each element of the defined domain 1 Identify the parameter (which domain is considering) + ‘name of the parameter’ + / elements of the domain and value / ; 2 instead of assigning a value directly to the parameter I can define an equation; 3 I can covert data from an excel file into a .gdx file : $call GDXXRW.EXE i=data.xlsx o=data.gdx par=a rng=capacity!A2:B3 rdim=1 par=b rng=demand!A2:B4 rdim=1 par=d rng=distance!A2:D4 rdim=1 cdim=1 $GDXIN data.gdx $LOAD a, b, d $GDXIN \ I and o are the name of the input and output files, par need the name of the parameter to import, rng is where we have to take the data from and rdim/cdim define the labels needed to import parameters defined over a set; names must…