apis/examples_matlab_control/transport5_8m_source.html

function transport5(varargin)


    % check workspace info from arguments

    if nargin > 0

        wsInfo = gams.control.WorkspaceInfo();

        wsInfo.systemDirectory = varargin{1};

        ws = gams.control.Workspace(wsInfo);

    else

        ws = gams.control.Workspace();

    end


    model = {

    ' Sets                                                               '

    '     i   canning plants   / seattle, san-diego /                    '

    '     j   markets          / new-york, chicago, topeka / ;           '

    '                                                                    '

    'Parameters                                                          '

    '     a(i)  capacity of plant i in cases                             '

    '       /    seattle     350                                         '

    '            san-diego   600  /                                      '

    '                                                                    '

    '     b(j)  demand at market j in cases                              '

    '       /    new-york    325                                         '

    '            chicago     300                                         '

    '            topeka      275  / ;                                    '

    '                                                                    '

    'Table d(i,j)  distance in thousands of miles                        '

    '                  new-york       chicago      topeka                '

    '    seattle          2.5           1.7          1.8                 '

    '    san-diego        2.5           1.8          1.4  ;              '

    '                                                                    '

    'Scalar f      freight in dollars per case per thousand miles  /90/ ;'

    'Scalar bmult  demand multiplier /1/;                                '

    '                                                                    '

    'Parameter c(i,j)  transport cost in thousands of dollars per case ; '

    '                                                                    '

    '          c(i,j) = f * d(i,j) / 1000 ;                              '

    '                                                                    '

    'Variables                                                           '

    '     x(i,j)  shipment quantities in cases                           '

    '     z       total transportation costs in thousands of dollars ;   '

    '                                                                    '

    'Positive Variable x ;                                               '

    '                                                                    '

    'Equations                                                           '

    '     cost        define objective function                          '

    '     supply(i)   observe supply limit at plant i                    '

    '     demand(j)   satisfy demand at market j ;                       '

    '                                                                    '

    'cost ..        z  =e=  sum((i,j), c(i,j)*x(i,j)) ;                  '

    '                                                                    '

    'supply(i) ..   sum(j, x(i,j))  =l=  a(i) ;                          '

    '                                                                    '

    'demand(j) ..   sum(i, x(i,j))  =g=  bmult*b(j) ;                    '

    '                                                                    '

    'Model transport /all/ ;                                             '

    'Scalar ms ''model status'', ss ''solve status'';                        '};

    model = sprintf('%s\n', model{:});


    % create a checkpoint

    cp = ws.addCheckpoint();


    % initialize a checkpoint by running a job

    t5 = ws.addJobFromString(model);

    t5.run(cp);


    % clear database

    t5.outDB.dispose();


    bmultlist = [0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3];


    % create a new Job that is initialized from the Checkpoint

    for i = 1:numel(bmultlist)

        job = sprintf('bmult=%f; solve transport min z use lp; ms=transport.modelstat; ss=transport.solvestat;', bmultlist(i));

        t5 = ws.addJobFromString(job, cp);

        t5.run();


        fprintf('Scenario bmult=%f:\n', bmultlist(i));

        fprintf('  Modelstatus: %s\n', gams.control.globals.ModelStat(t5.outDB.getParameter('ms').record.value).select);

        fprintf('  Solvestatus: %s\n', gams.control.globals.SolveStat(t5.outDB.getParameter('ss').record.value).select);

        fprintf('  Obj: %f\n', t5.outDB.getVariable('z').record.level);


        % clear database

        t5.outDB.dispose();

    end


    % remove working directory

    rmdir(ws.workingDirectory, 's');

end