# OR-Library

## J E Beasley

OR-Library is a collection of test data sets for a variety of OR problems.

A full list of the test data sets available in OR-Library can be found here.

## Generalised assignment problem

     There are 16 data files.

     The first 12 data files are gap1, gap2, ..., gap12.

     The problems in these data files were used in:

          I.H. Osman, "Heuristics for the Generalised Assignment Problem:
          Simulated Annealing and Tabu Search Approaches", OR Spektrum, Volume
          17, 211-225, 1995

          D. Cattrysse, M. Salomon and L.N. Van Wassenhove, "A
          set partitioning heuristic for the generalized
          assignment problem", European Journal of Operational Research, Volume
          72, 167-174, 1994

     The format for each of these data files is:

     number of different problem sets (P)
     for each problem set p (p=1,...,P) in turn:
     number of agents (m), number of jobs (n)
     for each agent i (i=1,...,m) in turn:
         cost of allocating job j to agent i (j=1,...,n)
     for each agent i (i=1,...,m) in turn:
         resource consumed in allocating job j to agent i (j=1,...,n)
     resource capacity of agent i (i=1,...,m)

     The problems in each data file have an associated notation as
     follows:

     c515-1    :    denotes a problem of type c with 5-agents and
                    15-jobs, problem number 1 in a group of
                    problems of the same size.

     The optimal solution values are given below for these
     problems when solved as maximisation problems.

     gap1           gap2           gap3           gap4
     c515-1  336    c520-1  434    c525-1  580    c530-1  656
     c515-2  327    c520-2  436    c525-2  564    c530-2  644
     c515-3  339    c520-3  420    c525-3  573    c530-3  673
     c515-4  341    c520-4  419    c525-4  570    c530-4  647
     c515-5  326    c520-5  428    c525-5  564    c530-5  664

     gap5           gap6           gap7           gap8
     c824-1  563    c832-1  761    c840-1  942    c848-1  1133
     c824-2  558    c832-2  759    c840-2  949    c848-2  1134
     c824-3  564    c832-3  758    c840-3  968    c848-3  1141
     c824-4  568    c832-4  752    c840-4  945    c848-4  1117
     c824-5  559    c832-5  747    c840-5  951    c848-5  1127

     gap9            gap10           gap11           gap12
     c1030-1  709    c1040-1  958    c1050-1  1139   c1060-1  1451
     c1030-2  717    c1040-2  963    c1050-2  1178   c1060-2  1449
     c1030-3  712    c1040-3  960    c1050-3  1195   c1060-3  1433
     c1030-4  723    c1040-4  947    c1050-4  1171   c1060-4  1447
     c1030-5  706    c1040-5  947    c1050-5  1171   c1060-5  1446

    The largest file is gap12 of size 20Kb (approximately).

    The final four data files are gapa, gapb, gapc and gapd.

    The problems in these data files were used in:
    P C Chu and J E Beasley "A genetic algorithm for the generalised
    assignment problem", Computers and Operations Research, Volume 24,
    pages 17-23, 1997.

    The format of these data files is as given above.

    File gapa contains type A problems
    File gapb contains type B problems
    File gapc contains type C problems
    File gapd contains type D problems

    The problems in these files are minimisation problems.

    The largest file is gapd of size 67Kb (approximately).

    The entire set of 16 files is of size 400Kb (approximately).

Click here to access these files

OTHER SOURCES

More generalised assignment instances can be found here