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IrisIris

Job shop

All formats · Reader spec · Cases and output

jobshop.iris reads job and machine counts, then one (machine, duration) pair per operation in each job. Machine numbers start at 0. Free text, # comments, and +++ separators are skipped. Each job must use every machine once. Data contains the counts and two-dimensional machine and duration arrays, plus name when present.

The format sources are the OR-Library job shop documentation and the format description at the start of jobshop1.txt, also used by JSPLIB. The reader spec is copied verbatim from Gecode’s job-shop.cpp.

  • or-library has three jobs and three machines, a description, separators, and instance handmade-or. Its params.json selects that instance by name.
  • jsplib has a different 3×3 instance with comment headers and no instance name.
  • duplicate-machine uses machine 0 twice in the first job. The reference reports E-CHECK-FAILED with record path [0].

The instances statement also supports files with several instances; these samples each contain one. These are hand-made samples under the repository’s MIT license. See the library README for case layout, validation, and Gecode notices.

Reader spec

From Gecode commit 5e7bbd5c26b0702c6fd652356b2289da0710ac3c. Source notices.

jobshop.irisView full reader spec
format jobshop


comment "#" "+++"
instances {
  sections skip other {
    "instance {name:word}" optional
    "{n_jobs:1..} {n_machines:1..}" last {
      check n_jobs <= (gecode.int_max - 2) / 2 / n_machines "there are too many jobs and machines"


      repeat n_jobs as jobs {
        each job
        repeat n_machines as steps {
          each step
          machine: 0..<n_machines
          duration: 0..
        }
      }
    }
  }


  check distinct(job.machine) "a job uses a machine twice; each job must use every machine once"
  check sum(j in jobs: sum(j.duration)) <= gecode.int_max "the total duration is too large"
}

Cases and output

Run the commands from the repository root. Successful reads show dzn, JSON, and a summary. Rejected inputs show the CLI's diagnostic and caret, with the stable error code beside it.

duplicate-machine

A job uses machine zero twice

Parameters: instance=handmade-invalid

InputView full input
instance handmade-invalid
3 3
0 2 0 3 2 1
1 1 2 4 0 2
2 3 0 1 1 2

E-CHECK-FAILED

check failed for record 1 of 'jobs': a job uses a machine twice; each job must use every machine once

Read rejectedRun from the repository root.
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/duplicate-machine/input.txt --dzn --param instance=handmade-invalid
formats/jobshop/cases/duplicate-machine/input.txt:3:1: check failed for record 1 of 'jobs': a job uses a machine twice; each job must use every machine once
     3 | 0 2 0 3 2 1
       | ^
while reading: instance [1]
spec: formats/jobshop/jobshop.iris:21

Input rejected

View full diagnosticDownload error JSON

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jsplib

Three-job instance with JSPLIB comments

InputView full input
# Hand-made JSPLIB style file
# Jobs and machines, then machine-duration pairs
3 3
0 3 2 2 1 4
1 2 0 1 2 3
2 4 1 3 0 2
dzn
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/jsplib/input.txt --dzn
dznView full dzn
n_jobs = 3;
n_machines = 3;
machine = [| 0, 2, 1
  | 1, 0, 2
  | 2, 1, 0 |];
duration = [| 3, 2, 4
  | 2, 1, 3
  | 4, 3, 2 |];
JSON
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/jsplib/input.txt --json
JSONView full json
{"iris":"0.1","entries":[{"name":"n_jobs","type":"int","depth":0,"value":3},{"name":"n_machines","type":"int","depth":0,"value":3},{"name":"machine","type":"int","depth":2,"value":[[0,2,1],[1,0,2],[2,1,0]]},{"name":"duration","type":"int","depth":2,"value":[[3,2,4],[2,1,3],[4,3,2]]}]}
Summary
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/jsplib/input.txt --summary
SummaryView full summary
formats/jobshop/cases/jsplib/input.txt [jobshop]
  n_jobs: int 3
  n_machines: int 3
  machine: int array 3 x 3
  duration: int array 3 x 3

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or-library

Named three-job instance with OR-Library wrappers

Parameters: instance=handmade-or

InputView full input
Hand-made OR-Library style file
+++++++++++++++++++++++++++++
instance handmade-or
+++++++++++++++++++++++++++++
Three jobs on three machines
3 3
0 2 1 3 2 1
1 1 2 4 0 2
2 3 0 1 1 2
dzn
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/or-library/input.txt --dzn --param instance=handmade-or
dznView full dzn
name = "handmade-or";
n_jobs = 3;
n_machines = 3;
machine = [| 0, 1, 2
  | 1, 2, 0
  | 2, 0, 1 |];
duration = [| 2, 3, 1
  | 1, 4, 2
  | 3, 1, 2 |];
JSON
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/or-library/input.txt --json --param instance=handmade-or
JSONView full json
{"iris":"0.1","entries":[{"name":"name","type":"string","depth":0,"value":"handmade-or"},{"name":"n_jobs","type":"int","depth":0,"value":3},{"name":"n_machines","type":"int","depth":0,"value":3},{"name":"machine","type":"int","depth":2,"value":[[0,1,2],[1,2,0],[2,0,1]]},{"name":"duration","type":"int","depth":2,"value":[[2,3,1],[1,4,2],[3,1,2]]}]}
Summary
iris read formats/jobshop/jobshop.iris formats/jobshop/cases/or-library/input.txt --summary --param instance=handmade-or
SummaryView full summary
formats/jobshop/cases/or-library/input.txt [jobshop]
  name: string "handmade-or"
  n_jobs: int 3
  n_machines: int 3
  machine: int array 3 x 3
  duration: int array 3 x 3

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