Replaces the geometry of the feature with a two-dimensional circular arc whose shape is estimated from the first, middle, and last point of the linear feature passed in. The result is an approximation only and unless the linear feature is previously known to be circular, the result could be completely different than the original feature.

This transformer is most useful when the feature was known to have been a circular arc originally, and was stroked into a line. This transformer can then be used to turn it back into an arc.

For example, a feature containing these points:



    0,2.236067977 (sqrt(5))

will be turned into an arc feature with this geometry:


and these attributes:

    fme_primary_axis     2.236067977

    fme_secondary_axis   2.236067977

    fme_start_angle      26

    fme_sweep_angle      63

    fme_rotation         0


Usage Notes

  • If the parameters for the arc are already available as attributes on the feature, then use the 2DArcReplacer or 3DArcReplacer transformer.


Input Ports

Output Ports


This transformer has no parameters.

Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.

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