ArcMap

ListTransformations

Summary

Returns a list of valid transformation methods for converting data from one spatial reference to another. An extent can be used to narrow the list of valid transformation methods for a specific geographic area.

Syntax

ListTransformations (from_sr, to_sr, {extent})
ParameterExplanationData Type
from_sr

The starting geographic coordinate system. Can be specified with a SpatialReference object, the name of the spatial reference, or a path to a projection file (.prj).

SpatialReference
to_sr

The final geographic coordinate system. Can be specified with a SpatialReference object, the name of the spatial reference, or a path to a projection file (.prj).

SpatialReference
extent

Only transformations that span the entire extent will be returned. The extent needs to be specified in coordinates from the in_sr. When working with data, the extent on a Describe object can be used.

Extent

Return Value

Data TypeExplanation
String

A list of valid transformation methods.

Code sample

ListTransformations example

Use ListTransformations to identify valid transformations for projecting from one coordinate system to another.

import arcpy

from_sr = arcpy.SpatialReference('WGS 1984')
to_sr = arcpy.SpatialReference('NAD 1927 StatePlane California VI FIPS 0406')

extent = arcpy.Extent(-178.217598182, 18.9217863640001,
                      -66.969270909, 71.4062354550001)
transformations = arcpy.ListTransformations(from_sr, to_sr, extent)

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