summaryStatistics

import summaryStatistics from "@arcgis/core/smartMapping/statistics/summaryStatistics.js";

Since: ArcGIS Maps SDK for JavaScript 4.2

Function for generating attribute statistics in a Layer based on values returned from a given field.

Known Limitations

SceneLayers must have the supportsRenderer and supportsLayerQuery capabilities enabled unless a predefined statistics object is provided to the statistics parameter of the method. To check a SceneLayer's capabilities, use the SceneLayer.getFieldUsageInfo() method. You cannot generate statistics using SQL expressions for client-side FeatureLayers in a SceneView. The normalizationType parameter only normalizes data returned by a field. It does not apply to values returned from a valueExpression or sqlExpression.

Functions

Name	Return Type	Object
`summaryStatistics`	`Promise<SummaryStatisticsResult>`

Function

Returns an object containing statistics describing a set of values returned from a field (or expression) in a Layer.

Signature: summaryStatistics (parameters: SummaryStatisticsParameters): Promise<SummaryStatisticsResult>

Parameters

Parameter	Type	Description	Required
parameters	`SummaryStatisticsParameters`	The function parameters.

Returns: Promise<SummaryStatisticsResult>
Returns a promise that resolves to SummaryStatisticsResult.

Examples

summaryStatistics({
  layer: featureLayer,
  valueExpression: "( ($feature.POP2020 - $feature.POP2010) / $feature.POP2010 ) * 100"
  view: mapView
}).then((stats) => {
  colorSlider.statistics = stats;
});

summaryStatistics({
  layer: featureLayer,
  field: "Population",
  normalizationType: "natural-log",
  sqlWhere: "Population > 0",
  numBins: 100
}).then((stats) => {
  histogramElement.average = stats.avg;
});