Derive New Locations

inputLayers

(Required)

A list of layers that will be used in the expressions parameter.

Each layer in the list can be:

• a URL to a feature service layer with an optional filter to select specific features, or
• a feature collection.

Examples:

• {"url": <feature service layer url>, "filter": <where clause>}
• {"layerDefinition": {}, "featureSet": {}, "filter": <where clause>}

[
    {"url": "http://someservices.arcgis.com/ees4FIJk4mpkX1ID/arcgis/rest/services/LAParkSitingData/FeatureServer/0"},
    {"url": "http://someservices.arcgis.com/ees4FIJk4mpkX1ID/arcgis/rest/services/LAParkSitingData/FeatureServer/1"},
    {"url": "http://someservices.arcgis.com/ees4FIJk4mpkX1ID/arcgis/rest/services/LAParkSitingData/FeatureServer/2"}
]

expressions

(Required)

This is a list of expressions. There are two types of expressions, attribute and spatial.

{
     "operator": "and",
     "layer": 0,
     "where": "STATUS = 'VACANT'"
}

• operator can be either and or or
• layer is the index of the layer in the inputLayers parameter.
• The where clause must be surrounded by double quotes.
• When dealing with text fields, values must be single-quoted ('VACANT').
• Date fields support all queries except LIKE. Dates are strings in YYYY:MM:DD hh:mm:ss format. Here's an example using the date field ObsDate:
  • "where": "ObsDate >= '1998-04-30 13:30:00' "

{
      "operator": "and",
      "layer": 0,
      "spatialRel": "withinDistance",
      "selectingLayer": 1,
      "distance": 10,
      "units": "miles"
}

• operator can be either and or or
• layer is the index of the layer in the inputLayers parameter. The result of the expression is features in this layer.
• spatialRel is the spatial relationship. There are nine spatial relationships.

  spatialRel	Description
  intersects notIntersects	A feature in layer passes the intersect test if it overlaps any part of a feature in selectingLayer, including touches (where features share a common point). intersects—If a feature in layer intersects a feature in selectingLayer, the portion of the feature in layer that intersects the feature in selectingLayer is included in the output. notIntersects—If a feature in layer intersects a feature in selectingLayer, the portion of the feature in layer that intersects the feature in selectingLayer is excluded from the output.
  withinDistance notWithinDistance	The within a distance relationship uses the straight-line distance between features in layer to those in selectingLayer. withinDistance—The portion of the feature in layer that is within the specified distance of a feature in selectingLayer is included in the output. notWithinDistance—The portion of the feature in layer that is within the specified distance of a feature in selectingLayer is excluded from output. You can think of this relationship as "is farther away than".
  contains notContains	A feature in layer passes this test if it completely surrounds a feature in selectingLayer. No portion of the contained feature can be outside the containing feature; however, the contained feature is allowed to touch the containing feature (that is, share a common point along its boundary). contains—If a feature in layer contains a feature in selectingLayer, the feature in layer is included in the output. notContains—If a feature in layer contains a feature in selectingLayer, the feature in the first layer is excluded from the output. Note: You can use the contains relationship with points and lines. For example, you have a layer of street centerlines (lines) and a layer of manhole covers (points), and you want to find streets that contain a manhole cover. You could use contains to find streets that contain manhole covers, but in order for a line to contain a point, the point must be exactly on the line (that is, in GIS terms, they are snapped to each other). If there is any doubt about this, use the withinDistance relationship with a suitable distance value.
  within notWithin	A feature in layer passes this test if it is completely surrounded by a feature in selectingLayer. The entire feature in layer must be within the containing feature; however, the two features are allowed to touch (that is, share a common point along its boundary). within—If a feature in layer is completely within a feature in selectingLayer, the feature in layer is included in the output. notWithin—If a feature in layer is completely within a feature in selectingLayer, the feature in layer is excluded from the output. Note: You can use the within relationship for points and lines, just as you can with the contains relationship. For example, your first layer contains points representing manhole covers and you want to find the manholes that are on street centerlines (as opposed to parking lots or other non-street features). You could use within to find manhole points within street centerlines, but in order for a point to contain a line, the point must be exactly on the line (that is, in GIS terms, they are snapped to each other). If there is any doubt about this, use the withinDistance relationship with a suitable distance value.
  nearest	A feature in the first layer passes this test if it is nearest to a feature in the second layer. nearest—If a feature in the first layer is nearest to a feature in the second layer, the feature in the first layer is included in the output.

• distance is the distance to use for the withinDistance and notWithinDistance spatial relationship.
• units is the units for distance. Values: Meters | Kilometers | Feet | Yards | Miles

An expression may be a list, which denotes a group. The first operator in the group indicates how the group expression is added to the previous expression. Grouping expressions is only necessary when you need to create two or more distinct sets of features from the same layer. One way to think of grouping is that without grouping, you would have to execute Derive New Locations multiple times and merge the results.

Following is an example where grouping is needed:

• You have a layer representing places that contain toxic chemicals. Each feature has an attribute, CHEMICAL, containing the name of the toxic chemical known to exist at the site.
• You want to find toxic sites containing Mercury or Selenium that are near a river (layer 0).
• You also want to find toxic sites containing Benzene or Lead that are near a park (layer 1).

[
    {
        "operator": "and",
        "layer": 0,
        "spatialRel": "withinDistance",
        "selectingLayer": 1,
        "distance": 0.5,
        "units": "Miles"
    },
    [
        {
            "operator": "and",
            "layer": 0,
            "where": "CHEMICAL = 'MERCURY'"
        },
        {
            "operator": "or",
            "layer": 0,
            "where": "CHEMICAL = 'SELENIUM'"
        },
    ],
    [
        {
            "operator": "or",
            "layer": 0,
            "spatialRel": "withinDistance",
            "selectingLayer": 2,
            "distance": 0.5,
            "units": "Miles"
        },
        [
            {
                "operator": "and",
                "layer": 0,
                "where": "CHEMICAL = 'BENZENE'"
            },
            {
                "operator": "or",
                "layer": 0,
                "where": "CHEMICAL = 'LEAD'"
            }
        ]
    ]
]

outputName

If provided, the task will create a feature service of the results. You define the name of the service. If outputName is not supplied, the task will return a feature collection.

{
  "serviceProperties": {
    "name": "<service name>"
  }
}

context

Context contains additional settings that affect task execution. For Derive New Locations, there are two settings.

1. Extent (extent)—a bounding box that defines the analysis area. Only those features in the input list inputLayers that intersect the bounding box will be analyzed.
2. Output Spatial Reference (outSR)—the output features will be projected into the output spatial reference.

{
"extent" : {extent}
"outSR" : {spatial reference}
}

f

The response format. The default response format is html.

Values: html | json

resultLayer

{"url": 
"http://<analysis url>/DeriveNewLocations/jobs/<jobId>/results/resultLayer"}

The result has properties for parameter name, data type, and value. The contents of value depends upon the outputName parameter provided in the initial request.

• If outputName was provided, value contains the url to the feature service layer.

  {
  "paramName":"resultLayer", 
  "dataType":"GPString",
  "value":{"url":"<hosted featureservice layer url>"}
  }
  

• If outputName was not provided, value contains a feature collection.

  {
  "paramName":"resultLayer",
  "dataType":"GPString",
  "value":{"layerDefinition": {}, "featureSet": {}}
  }
  

See Feature Output for more information about how the result layer or collection is accessed.