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Class: GeographicTransformation

require(["esri/geometry/GeographicTransformation"], function(GeographicTransformation) { /* code goes here */ });

Description

(Added at v3.24)
Projecting your data between coordinate systems sometimes requires transforming between geographic coordinate systems. Geographic transformations are used to transform coordinates between spatial references that have different geographic coordinate systems, and thus different datums. Using the most suitable transformation ensures the best possible accuracy when converting geometries from one spatial reference to another. The projection module provides the gettransformation() and getTransformations() methods which return the default geographic transformation for the given projection or a list of suitable geographic transformations.

Things to consider:

See also:
SpatialReference References Guide
What are map projections
Choosing an appropriate transformation
Geographic transformation methods

Samples

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Constructors

NameSummary
new GeographicTransformation(params?)Creates a new GeographicTransformation object.

Properties

NameTypeSummary
stepsGeographicTransformationStep[]Geographic transformation steps.

Methods

NameReturn typeSummary
getInverse()GeographicTransformationReturns the inverse of the geographic transformation, calling this method or null if the transformation is not invertible.
Constructor Details

new GeographicTransformation(params?)

Creates a new GeographicTransformation object.
Parameters:
<Object> params Optional See options descriptions for further information.
params properties:
<GeographicTransformationStep[]> steps Optional Geographic transformation steps. Each step represents a geographic transformation that will be used in the process of transforming coordinates from one geographic coordinate system to another.
Property Details
Geographic transformation steps. Each step represents a geographic transformation that will be used in the process of transforming coordinates from one geographic coordinate system to another.
Method Details

getInverse()

Returns the inverse of the geographic transformation, calling this method or null if the transformation is not invertible. The inverse of a transformation converts coordinates using the same method and parameters, but in the opposite direction of the original object. For example, if the original object represents the NAD_1983_HARN_To_NAD_1983_NSRS2007_1 transformation, then the inverse will transform from NAD 83 (NSRS 2007) to NAD 83 (HARN).
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