histogram

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

Since: ArcGIS Maps SDK for JavaScript 4.2

Generates a histogram based on data in a Layer for a given field. The returned object can be used for displaying a histogram in the UI within visualization authoring applications and analytical apps that query and display statistics.

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
`histogram`	`Promise<HistogramResult>`

Function

Generates a histogram for data returned from a field in a given layer. The returned object can be used for displaying a histogram to the UI in visualization authoring applications and analytical apps that query and display statistics.

Signature: histogram (parameters: HistogramParameters): Promise<HistogramResult>

Parameters

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

Returns: Promise<HistogramResult>
Resolves to a HistogramResult object.

Examples

histogram({
  layer: featureLayer,
  valueExpression: "( ($feature.POP2020 - $feature.POP2010) / $feature.POP2010 ) * 100"
  view: mapView,
  numBins: 30
}).then((histogramResult) => {
  colorSlider.histogram = histogramResult;
});

histogram({
  layer: featureLayer,
  field: "Population",
  normalizationType: "natural-log",
  sqlWhere: "Population > 0",
  numBins: 100
}).then((histogramResult) => {
  const histogramElement = document.createElement("arcgis-histogram");
  // Set histogram properties based on the histogramResult
  histogramElement.min = histogramResult.minValue;
  histogramElement.max = histogramResult.maxValue;
  histogramElement.bins = histogramResult.bins;
});