Determine Travel Cost Paths to Destinations

Determine Travel Cost Paths to Destinations diagram

The Determine Travel Cost Paths To Destinations task calculates specific paths between known sources and known destinations.

Example applications include the following:

  • Find the best route for a new road in terms of construction costs.
  • Identify the path to take from several suburban locations (sources) to the closest shopping mall (destination).

The least-cost path is one cell wide, and it travels from the destination to the source. This path is guaranteed to be the least expensive route relative to the cost units defined by the original cost raster that was input into the weighted-distance function.

Request URL

http://<raster analysis url>/DetermineTravelCostPathstoDestinations/submitJob

Request Parameters

The following table lists the parameters with syntax and details for each.

ParameterDescription

inputDestinationRasterOrFeatures

(Required)

The layer that defines the destinations used to calculate the distance. The layer can be raster or feature.

Raster input

Syntax: This parameter can be specified as a Portal Item ID, a URL to a raster image service layer, or a cloud raster dataset.

Domain: Integer raster

Examples:

  • "inputDestinationRasterOrFeatures":{"itemID": <portal item id>}
  • "inputDestinationRasterOrFeatures":{"url": <image service layer url>}

Feature input

Syntax: This parameter can be specified as one of the following:

  • A URL to a feature service layer
  • A feature collection

Examples:

  • "inputDestinationRasterOrFeatures":{"url": <feature service layer url>}
  • "inputDestinationRasterOrFeatures":{"layerDefinition": {}, "featureSet": {}}

inputCostDistanceRaster

(Required)

The cost distance raster used to determine the least-cost path from the destination locations to a source.

Typically the Calculate Travel Cost task is used to create this input.

Syntax: This parameter can be specified as a Portal Item ID, a URL to a raster image service layer, or a cloud raster dataset.

Examples:

  • "inputCostDistanceRaster": {"itemId": <portal item id>}
  • "inputCostDistanceRaster": {"url": <image service layer url>}

inputCostBacklinkRaster

(Required)

A raster defining the return to a source via the least-cost path.

Typically the Calculate Travel Cost task is used to create this input.

Syntax: This parameter can be specified as a Portal Item ID, a URL to a raster image service layer, or a cloud raster dataset.

Examples:

  • "inputCostBacklinkRaster": {"itemId": <portal item id>}
  • "inputCostBacklinkRaster": {"url": <image service layer url>}

outputName

(Required)

The output image service name that will be created.

Syntax: A JSON object describes the name of the output or the output raster.

You can specify the name, or you can create an empty service using Portal Admin Sharing API and use the return JSON object as input to this parameter.

Output name example:

"outputName":{"serviceProperties":{"name":"testrasteranalysis"}}

Output raster examples:

"outputName":{"itemId": <portal item id>}
"outputName":{"url": <image service url}
"outputName":{"serviceProperties":
                  {"name":"testrasteranalysis",
                   "serviceUrl":"http://<server name>/server/rest/services/Hosted/testrasteranalysis/ImageServer"},
                   "itemProperties":{"itemId":"8cfbd3ec25584d0d8f4ed23b8ff7c43b","folderId":"sdfwerfbd3ec25584d0d8f4"}}

destinationField

A field on theinputDestinationRasterOrFeatures layer that holds the values that define each destination.

It can be an integer or a string field of the source dataset.

Domain: Integer or string field

Default: Value

Example:

  • "destinationField": "Dest1"

pathType

A keyword defining the manner in which the values and zones on the input destination data will be interpreted in the cost path calculations.

Syntax: A string describing the path type, which can be one of the following:

  • EACH_CELL—For each cell with valid values on the input destination data, a least-cost path is determined and saved on the output raster. With this option, each cell of the input destination data is treated separately, and a least-cost path is determined for each from cell. This is the default.
  • EACH_ZONE—For each zone on the input destination data, a least-cost path is determined and saved on the output raster. With this option, the least-cost path for each zone begins at the cell with the lowest cost distance weighting in the zone.
  • BEST_SINGLE—For all cells on the input destination data, the least-cost path is derived from the cell with the minimum of the least-cost paths to source cells.

Example:

  • "pathType": "EACH_ZONE"

context

Contains additional settings that affect task execution.

This task has the following settings:

  • Extent (extent)—A bounding box that defines the analysis area.
  • Output Spatial Reference (outSR)—The output raster will be projected into the output spatial reference.
  • Snap Raster (snapRaster)—The output raster will have its cells aligned with the specified snap raster.
  • Cell Size (cellSize)—The output raster will have the resolution specified by cell size.
  • Mask (mask)—Only cells that fall within the analysis mask will be considered in the operation.

f

The response format. The default response format is html.

Values: html | json

Response

When you submit a request, the task assigns a unique job ID for the transaction.

Syntax:

{
"jobId": "<unique job identifier>",
"jobStatus": "<job status>"
}

After the initial request is submitted, you can use the jobId to periodically check the status of the job and messages as described in Checking job status. Once the job has successfully completed, you use the jobId to retrieve the results. To track the status, you can make a request of the following form:

http://<raster analysis url>/DetermineTravelCostPathstoDestinations/jobs/<jobId>

Accessing results

When the status of the job request is esriJobSucceeded, you can access the results of the analysis by making a request of the following form:

http://<raster analysis url>/jobs/<jobId>/results/outputRaster?token=<your token>&f=json

ParameterDescription

outputRaster

This is the output travel cost path raster item ID and URL.

Example:

{"url": 
"http://<raster analysis url>/DetermineTravelCostPathstoDestinations/jobs/<jobId>/results/outputRaster"}

The result has properties for parameter name, data type, and value. The content of value is always the itemid of the output raster dataset and the image service URL. For example:

{
    "paramName": "outRaster",
    "dataType": "GPString",
    "value": {
        "itemId": "f121390b85ef419790479fc75b493efd", 
        "url": "https://<server name>/arcgis/rest/services/Hosted/<service name>/ImageServer"
    }
}