net1-v2.json

{
  "PROBLEM": {
    "NAME": "general_transshipment v2.0",
    "REFERENCE": "https://ampl.com/BOOK/EXAMPLES/EXAMPLES2/net1.mod",
    "AUTHOR": "Jeremy A. Bloom (jeremyblmca@gmail.com)",
    "NOTICES": "Copyright © 2019 Jeremy A. Bloom"
  },
  "INPUT_DATA_MODEL": {
    "cities": {
      "*city":              "String",
      "netSupply":          "Double"
    },
    "links": {
      "*origin":            "String",
      "*destination":       "String",
      "cost":               "Double",
      "capacity":           "Double"
    }
  },
  "Output_Data_Model": {
    "ship": {
      "*origin(city)":      "String",
      "*destination(city)": "String",
      "packages":           "Double"
    }
  },
  "DATA": {
    "cities": [
      {"city": "PITT", "netSupply": 450.0},
      {"city": "NE", "netSupply": 0.0},
      {"city": "SE", "netSupply": 0.0},
      {"city": "BOS", "netSupply": -90.0},
      {"city": "EWR", "netSupply": -120.0},
      {"city": "BWI", "netSupply": -120.0},
      {"city": "ATL", "netSupply": -70.0},
      {"city": "MCO", "netSupply": -50.0}
    ],
    "links": [
      {"origin": "PITT", "destination": "NE", "cost": 2.5, "capacity": 250.0},
      {"origin": "PITT", "destination": "SE", "cost": 3.5, "capacity": 250.0},
      {"origin": "NE", "destination": "BOS", "cost": 1.7, "capacity": 100.0},
      {"origin": "NE", "destination": "EWR", "cost": 0.7, "capacity": 100.0},
      {"origin": "NE", "destination": "BWI", "cost": 1.3, "capacity": 100.0},
      {"origin": "SE", "destination": "EWR", "cost": 1.3, "capacity": 100.0},
      {"origin": "SE", "destination": "BWI", "cost": 0.8, "capacity": 100.0},
      {"origin": "SE", "destination": "ATL", "cost": 0.2, "capacity": 100.0},
      {"origin": "SE", "destination": "MCO", "cost": 2.1, "capacity": 100.0}
    ]
  },
  "VARIABLES": [
    {
      "NAME": "ship",
      "TYPE": "Continuous",
      "INDEX": "links",
      "BOUNDS": {"LOWER": "0.0", "UPPER": "ship*.capacity"}
    }
  ],
  "CONSTRAINTS": [
    {
      "NAME": "balance",
      "TYPE": "CONTINUOUS",
      "INDEX": "cities",
      "BOUNDS": {"LOWER": "balance*.netSupply", "UPPER": "balance*.netSupply"}
   }
  ],
  "DECISION_EXPRESSIONS": [
    {
      "NAME": "totalCost",
      "TYPE": "LINEAR",
      "INDEX": "SELF",
      "SENSE": "MINIMIZE"
    }
  ],
  "COEFFICIENTS": [
    {
      "NAME": "balance_shipFrom",
      "CONSTRAINTS": "balance",
      "VARIABLES": "ship",
      "CONDITION": "balance*.city == ship*.origin",
      "ENTRIES": "1.0"
    },
    {
      "NAME": "balance_shipTo",
      "CONSTRAINTS": "balance",
      "VARIABLES": "ship",
      "CONDITION": "balance*.city == ship*.destination",
      "ENTRIES": "-1.0"
    },
    {
      "NAME": "total_ship",
      "DECISION_EXPRESSIONS": "totalCost",
      "VARIABLES": "ship",
      "CONDITION": "ship* MATCHES links",
      "ENTRIES": "links.cost"
    }
  ]
}