collections.md

Collections

CoverageJSON has a compact coverage collection structure which allows to move repeated information like parameters and reference systems to the collection level. It is especially useful for uniform collections but can also be used for any other collection where each coverage may have a different set of parameters or reference systems.

Example:

{
  "type" : "CoverageCollection",
  "domainType" : "VerticalProfile",
  "parameters" : {
    "PSAL": {
      "type" : "Parameter",
      "description" : {
        "en": "The measured salinity, in practical salinity units (psu) of the sea water"
      },
      "unit" : {
        "symbol" : "psu"
      },
      "observedProperty" : {
        "id": "http://vocab.nerc.ac.uk/standard_name/sea_water_salinity/",
        "label" : {
          "en": "Sea Water Salinity"
        }
      }
    }
  },
  "referencing": [{
    "coordinates": ["x","y"],
    "system": {
      "type": "GeographicCRS",
      "id": "http://www.opengis.net/def/crs/OGC/1.3/CRS84"
    }
  }, {
    "coordinates": ["z"],
    "system": {
      "type": "VerticalCRS",
      "cs": {
        "axes": [{
          "name": {
            "en": "Pressure"
          },
          "direction": "down",
          "unit": {
            "symbol": "Pa"
          }
        }]
      }
    }
  }, {
    "coordinates": ["t"],
    "system": {
      "type": "TemporalRS",
      "calendar": "Gregorian"
    }
  }],
  "coverages": [
    {
      "type" : "Coverage",
      "domain" : {
        "type": "Domain",
        "axes": {
          "x": { "values": [-10.1] },
          "y": { "values": [-40.2] },
          "z": { "values": [ 5, 8, 14 ] },
          "t": { "values": ["2013-01-13T11:12:20Z"] }
        }
      },
      "ranges" : {
        "PSAL" : {
          "type" : "NdArray",
          "dataType": "float",
          "shape": [3],
          "axisNames": ["z"],
          "values" : [ 43.7, 43.8, 43.9 ]
        }
      }
    }, {
      "type" : "Coverage",
      "domain" : {
        "type": "Domain",
        "axes": {
          "x": { "values": [-11.1] },
          "y": { "values": [-45.2] },
          "z": { "values": [ 4, 7, 9 ] },
          "t": { "values": ["2013-01-13T12:12:20Z"] }
        }
      },
      "ranges" : {
        "PSAL" : {
          "type" : "NdArray",
          "dataType": "float",
          "shape": [3],
          "axisNames": ["z"],
          "values" : [ 42.7, 41.8, 40.9 ]
        }
      }
    }]
}

For more details, see the Collection section of the specification.