dojo.require("esri.dijit.analysis.FindHotSpots");
Description
(Added at v3.7)
The FindHotSpots widget finds statistically significant clusters of incident points, weighted points, or weighted polygons. For incident data, the analysis field (weight) is obtained by aggregation. The output is a hot spot layer, where hot spots are shown in red and cold spots in blue.
View the
ArcGIS REST API documentation for the
Find Hot Spots task for more details.
Samples
Search for
samples that use this class.
Class hierarchy
esri/dijit/analysis.AnalysisBase
|_esri/dijit/analysis.FindHotSpots
Constructors
CSS
esri/dijit/analysis/FindHotSpots | Download source
Properties
aggregationPolygonLayers | FeatureLayer[] | An array of feature layer candidates to be selected as the aggregation polygon layer. |
analysisField | String | The numeric field in the AnalysisLayer that will be analyzed. |
analysisGpServer | String | The URL to the analysis service, for example "http://analysis.arcgis.com/arcgis/rest/services/tasks/GPServer". |
analysisLayer | FeatureLayer | The feature layer for which hot spots will be calculated. |
boundingPolygonLayer | FeatureLayer | A layer of bounding areas to answer the question: Within the bounding areas, are there any locations with unexpectedly high or low point concentrations? (Added at v3.12). |
boundingPolygonLayers | FeatureLayer[] | An array of feature layer candidates to be selected as the bounding polygon layer. |
folderId | String | Sets the selected folder of the select folder dropdown, based on the provided folderId , when showSelectFolder is true. |
folderName | String | Sets the selected folder of the select folder dropdown, based on the provided folderName , when showSelectFolder is true. |
map | Map | Reference to the map object. |
outputLayerName | String | The name of the output layer to be shown in the Result layer name inputbox. |
portalSelf | Object | The self response of the Portal. |
portalUrl | String | The URL to the ArcGIS.com site or in-house portal where the GP server is hosted, for example "http://www.arcgis.com". |
returnFeatureCollection | Boolean | When true, returns the result of analysis as a client-side feature collection. |
returnProcessInfo | Boolean | Return a report of the analysis process. |
showChooseExtent | Boolean | When true, the choose extent checkbox will be shown. |
showCloseIcon | Boolean | Indicates whether to show the close icon on the widget's user interface. |
showCredits | Boolean | When true, the show credit option is visible. |
showHelp | Boolean | When true, the help links will be shown. |
showReadyToUseLayers | Boolean | When true , adds an option to the UI that allows users to choose ready to use analysis layers from the Living Atlas Analysis Layers. |
showSelectAnalysisLayer | Boolean | Indicates whether to display a drop down menu listing valid input analysis layers. |
showSelectFolder | Boolean | When true, the select folder dropdown will be shown. |
title | String | Overrides the default widget title with a custom title. |
Methods
Events
[ On Style Events | Connect Style Event ]
All On Style event listeners receive a single event object. Additionally, the event object also contains a 'target' property whose value is the object which fired the event.
Constructor Details
Creates a new FindHotSpots dijit using the given DOM node.
Parameters:
<Object > params |
Required |
Various options to configure this dijit. Refer to the Options table below. |
<Node | String > srcNodeRef |
Required |
Reference or id of a HTML element that this dijit is rendered into. |
params
properties:
<FeatureLayer[] > aggregationPolygonLayers |
Required |
An array of feature layer candidates to be selected as the aggregation polygon layer. The aggregation polygon layer defines the boundaries within which incidents will be aggregated before analysis. When this layer is specified, the number of incidents within each polygon will be counted. These polygons with their incident counts will be used as the input features for analysis. The geometry of output hot spots layer will also be based on these polygons.
For example, if you are analyzing traffic accidents in a city and the outlines of census tracts in that city are selected as bounding polygons, the output hot spots value will be based on each census tract instead of each accident's location.
This parameter should be used only when analysisLayer is a point layer. It will be shown as an option under Choose an analysis field. This option is available only when analysisField is not selected.
* Required. |
<String > analysisField |
Optional |
The numeric field in the AnalysisLayer that will be analyzed. When the AnalysisLayer is a point FeatureLayer, rather than a field name the AnalysisField may be "NO ANALYSIS FIELD". |
<String > analysisGpServer |
Optional |
The URL to the GPServer used to execute an analysis job.
* Required when portalUrl is not specified. |
<FeatureLayer > analysisLayer |
Required |
The feature layer for which hot spots will be calculated. Can be a polygon or a point layer.
* Required. |
<FeatureLayer[] > boundingPolygonLayers |
Required |
An array of feature layer candidates to be selected as the bounding polygon layer. The bounding polygon layer defines the study area within which incidents could have occurred. When this layer is specified, all locations within this layer will be analyzed, whether any incident occurred at a location or not. When not specified, only locations with at least one point (incident) will be included in the analysis.
For example, if you are analyzing boating accidents in a harbor, the outline of the harbor might provide a good boundary for where accidents could occur. When no bounding areas are provided, only locations with at least one point will be included in the analysis.
This parameter should be used only when the analysisLayer is a point layer. It will be shown as an option under Choose an analysis field. This option is available only when analysisField is not selected.
* Required. |
<Boolean > isProcessInfo |
Optional |
When true, make process info to get analysis report. |
<Map > map |
Optional |
Reference to the map object.
* Required when showChooseExtent is true . |
<String > outputLayerName |
Optional |
The name of the output layer to be shown in the Result layer name inputbox. If not specified, "Hot Spots ${analysis_layer_title}" will be shown by default. |
<String > portalUrl |
Optional |
The url to the ArcGIS.com site or in-house portal where the GP server is hosted.
* Required when analysisGpServer is not specified. |
<Boolean > returnFeatureCollection |
Optional |
When true, returns the result of analysis as a client-side feature collection. This value determines whether or not the result will be saved and published on a user's arcgis.com account. |
<Boolean > showChooseExtent |
Optional |
When true, the choose extent checkbox will be shown. |
<Boolean > showCredits |
Optional |
When true, the show credit option is visible. |
<Boolean > showHelp |
Optional |
When true, the help links will be shown. |
<Boolean > showSelectFolder |
Optional |
When true, the select folder dropdown will be shown. This parameter should be used when you want to allow users to select a folder in their arcgis.com account where the output feature layer will be exported as a service. When returnFeatureCollection is set to true , this option becomes invalid since no arcgis.com item will be created. |
Sample: var findHotSpots = new esri.dijit.analysis.FindHotSpots({
analysisLayer: inputlayer,
boundingPolygonLayers: polygonLayers,
aggregationPolygonLayers: polygonLayers,
map: map,
portalUrl: "http://www.arcgis.com"
}, "analysis-tool");
Property Details
An array of feature layer candidates to be selected as the aggregation polygon layer. The aggregation polygon layer defines the boundaries within which incidents will be aggregated before analysis. When this layer is specified, the number of incidents within each polygon will be counted. These polygons with their incident counts will be used as the input features for analysis. The geometry of output hot spots layer will also be based on these polygons.
For example, if you are analyzing traffic accidents in a city and the outlines of census tracts in that city are selected as bounding polygons, the output hot spots value will be based on each census tract instead of each accident's location.
This parameter should be used only when analysisLayer
is a point layer. It will be shown as an option under Choose an analysis field. This option is available only when analysisField
is not selected.
The numeric field in the AnalysisLayer that will be analyzed. When the AnalysisLayer is a point FeatureLayer, rather than a field name the AnalysisField may be "NO ANALYSIS FIELD".
The URL to the analysis service, for example "http://analysis.arcgis.com/arcgis/rest/services/tasks/GPServer".
The feature layer for which hot spots will be calculated. Can be a polygon or a point layer.
A layer of bounding areas to answer the question: Within the bounding areas, are there any locations with unexpectedly high or low point concentrations? (Added at v3.12)
An array of feature layer candidates to be selected as the bounding polygon layer. The bounding polygon layer defines the study area within which incidents could have occurred. When this layer is specified, all locations within this layer will be analyzed, whether any incident occurred at a location or not. When not specified, only locations with at least one point (incident) will be included in the analysis.
For example, if you are analyzing boating accidents in a harbor, the outline of the harbor might provide a good boundary for where accidents could occur. When no bounding areas are provided, only locations with at least one point will be included in the analysis.
This parameter should be used only when the analysisLayer
is a point layer. It will be shown as an option under Choose an analysis field. This option is available only when analysisField
is not selected.
Sets the selected folder of the select folder dropdown, based on the provided folderId
, when showSelectFolder
is true. When folderId
and folderName
are both provided, folderId
has higher precedence. (Added at v3.13)
Sets the selected folder of the select folder dropdown, based on the provided folderName
, when showSelectFolder
is true. (Added at v3.13)
Reference to the map object.
The name of the output layer to be shown in the Result layer name inputbox. If not specified, "Hot Spots ${analysis_layer_title}"
will be shown by default.
The self response of the Portal. When set, optimizes performance to reuse self calls made by the widget. For more documentation on the properties of this object, see the
Portal Self ArcGIS REST API documentation.
(Added at v3.14)
The URL to the ArcGIS.com site or in-house portal where the GP server is hosted, for example "http://www.arcgis.com". (Added at v3.7)
When true, returns the result of analysis as a client-side feature collection. This value determines whether or not the result will be saved and published on a user's arcgis.com account.
Known values: true | false
Default value: false
Return a report of the analysis process. (Added at v3.12)
Known values: true | false
Default value: true
When true, the choose extent checkbox will be shown.
Known values: true | false
Default value: true
Indicates whether to show the close icon on the widget's user interface. (Added at v3.14)
Known values: true | false
Default value: true
When true, the show credit option is visible.
Known values: true | false
Default value: true
When true, the help links will be shown.
Known values: true | false
Default value: true
When
true
, adds an option to the UI that allows users to choose ready to use analysis layers from the
Living Atlas Analysis Layers.
(Added at v3.14) Known values: true | false
Default value: true
Indicates whether to display a drop down menu listing valid input analysis layers. (Added at v3.14)
Known values: true | false
Default value: true
When true, the select folder dropdown will be shown. This parameter should be used when you want to allow users to select a folder in their arcgis.com account where the output feature layer will be exported as a service.
Known values: true | false
Default value: false
Overrides the default widget title with a custom title. Set this value in the initial constructor parameters.
For example, instead of using the default title (for example "Find Hot Spots"), you can use this property to change the default to a customized title for the tool (for example "Areas with High Crime"). (Added at v3.14)
Method Details
Cancels an analysis job that is being processed.
Parameters:
<Object > jobInfo |
Required |
An object containing job information including job ID, status, message, etc returned by the job-status event. |
Starts checking the analysis job status for the given jobId. (Added at v3.12)
Parameters:
<String > jobId |
Required |
Job id of the analysis job to check. |
Starts an analysis tool.
Parameters:
<String > params |
Required |
See the object specifications table below for the structure of the params object. |
Object Specifications: <params
>
<Object > itemParams |
Optional |
Parameters for creating the output service item. Refer to the ArcGIS REST API - Add Item help topic for a list of available parameters. Only used when the analysis task creates a hosted service. |
<Object > jobParams |
Required |
The input job parameters. Required parameters vary from class to class. Refer to the Analysis REST API Documentation for details (Under the Request Parameters section of each task). When creating a hosted service, a layer name is required. |
Sample: var params = {
itemParams: {
description: "Item description.",
snippet: "A short summary about this item.",
tags: "<tag1>, <tag2>, <tag3>, ... ",
typeKeywords: "<typeKeyword1>, <typeKeyword2>, <typeKeyword3>, ... "
},
jobParams: {
outputLayerName: "{\"serviceProperties\":{\"name\":\"Name of the output feature service\"},\"itemProperties\":{\"itemId\":\"<itemId>\"}}",
...
}
}
analysisBase.execute(params);
Gets credits estimate for a specific analysis job. This method returns a deferred object. The callback function has an object containing the number of records to be processed and the estimated credit cost for this job.
Parameters:
<String > toolName |
Required |
The name of the analysis tool from which a credits estimate will be returned. |
<String > jobParams |
Required |
The input job parameters. This value should be the same as the jobParams property of an analysis tool dijit. Refer to the jobParams property of this class for detailed syntax. |
Sample:
analysisBase.getCreditsEstimate("FindHotSpots",{
AnalysisLayer: layer._json,
context: '{"outSR":{"wkid":102100}}',
isProcessInfo: true,
returnFeatureCollection: true
}).then(function(result){
console.log(result);
});
//the "result" argument above:
//{
// "cost": 1.472,
// "totalRecords": 1472,
//}
Finalizes the creation of the widget. (Added at v3.12)
Event Details
[ On Style Events | Connect Style Event ]
Fires when close icon is clicked or when run analysis button is clicked. (Added at v3.7)
Fires when the drawn boundaries option is activated. Only valid when using the FindHotSpots or ExtractData widget. A typical usage is to disable the zoom/pan/popup handlers when drawing is activated. (Added at v3.7)
Fires when the drawn boundaries option is deactivated. Only valid when using the FindHotSpots or ExtractData widget. A typical usage is to enable the zoom/pan/popup handlers when drawing is deactivated. (Added at v3.7)
Fires when the job in cancelled. (Added at v3.7)
Event Object Properties:
<Object > response |
An GP job object returned by the GP server. Refer to the GP Job and the Checking job status topics in the ArcGIS REST API Documentation for more information and syntax.
{
"inputs": {},
"jobId": <job id>,
"jobStatus": <job status>,
"messages": <an array of message text>,
"results": {}
} |
Fires when the job fails. (Added at v3.7)
Event Object Properties:
<Object > error |
The error message returned by a failed job.{
"analysisReport": <analysis report message>,
"dataType": <analysis report message>,
"paramName": < parameter name >,
"value": <output item info | feature collection>
} |
Fires after the job fetches result data. The returned argument contains the output value (either a feature collection or a url to the hosted service), which you may add to the map as a feature layer. (Added at v3.7)
Event Object Properties:
<Object > result |
An object containing the resulted message and value. Based on the GP result object returned by the GP server with the analysisReport property added.
If output is a feature collection, value is a feature collection object; if output is a hosted arcgis.com feature service, value is an object with item information including ID and URL. Refer to the ArcGIS REST API documentation - Feature Output for more information.{
"analysisReport": <analysis report message>,
"dataType": <analysis report message>,
"paramName": < parameter name >,
"value": <output item info | feature collection>
} |
Sample: analysisTool.on("job-result", function(result){
var featureLayer = new FeatureLayer(result.value['url'] || result.value);
map.addLayer(featureLayer);
})
Fires when the job execution status is received. (Added at v3.7)
Event Object Properties:
<Object > jobInfo |
An object containing job information including job ID, status, message, etc. Based on the GP job object returned by the GP server with the jobParam property attached. Refer to the GP Job and the Checking job status topics in the ArcGIS REST API Documentation for more information and syntax.{
"inputs": {},
"jobParams": <job parameters>,
"jobId": <job id>,
"jobStatus": <job status>,
"messages": <an array of message text>,
"results": {}
} |
Fires when the job is submitted to the server for asynchronous processing. (Added at v3.7)
Event Object Properties:
<Object > params |
The input job parameters. |
Fires when the job succeeds. (Added at v3.7)
Event Object Properties:
<Object > jobInfo |
An object containing job information including job ID, status, message, etc. Based on the GP job object returned by the GP server with the jobParam property attached. Refer to the GP Job and the Checking job status topics in the ArcGIS REST API Documentation for more information and syntax.
This returned object can be passed into the cancel(jobInfo) method to terminate a job.{
"inputs": {},
"jobParams": <job parameters>,
"jobId": <job id>,
"jobStatus": <job status>,
"messages": <an array of message text>,
"results": {}
} |
Fires when the execute method is called. (Added at v3.7)
Event Object Properties:
<Object > params |
The input job parameters. |
Fires when the job is closed.
Fires when the job is submitted after createservice is called.
Event Object Properties:
<Object > params |
The input job parameters. This value should be the same as the jobParams property of an analysis tool dijit. Refer to the jobParams property of this class for detailed syntax. |
Fires when the job in cancelled.
Event Object Properties:
<Object > response |
An response object returned by a GP server.{
"inputs": {},
"jobId": "j04c9eb46b5fd442ba93001a8682d551c",
"jobStatus": "esriJobCancelled",
"messages": <an array of message text>,
"results": {}
} |
Fires when the job fails.
Event Object Properties:
<Error > error |
The error message returned by a failed job. |
Fires after the job fetches result data.
Event Object Properties:
<Object > result |
An object containing the following properties:{
"_ssl": false,
"analysisReport": "report message",
"dataType": "GPString",
"paramName": "hotSpotsResultLayer",
"value": <a feature collection object>
} |
Fires when the job execution status is received.
Event Object Properties:
<Object > jobInfo |
An object containing job ID, job status, and the initial input parameters.{
jobId: "jf07254b24ffb4e67ba4daa311de45f00",
jobStatus: "esriJobSubmitted",
jobParams: <the jobParams property of this analysis tool>
} |
Fires when a job is submitted to the server for asynchronous processing.
Event Object Properties:
<Object > params |
The input job parameters. The input job parameters. This value should be the same as the jobParams property of an analysis tool dijit. Refer to the jobParams property of this class for detailed syntax. |
Fires when the job succeeds.
Event Object Properties:
<Object > jobInfo |
An object containing job ID, job status, the initial input parameters, messages and result info.{
"inputs": {},
"jobId": "j00177ce97f8a4d01b0e8a44d735f5667",
"jobParams": <the jobParams property of this analysis tool>,
"jobStatus": "esriJobSucceeded"
"messages": <an array of message text>,
"results": {
"hotSpotsResultLayer": {
"paramUrl": "results/hotSpotsResultLayer"
},
"processInfo": {
"paramUrl": "results/processInfo"
}
}
} |
Fires when the job is saved.