3DArcReplacer
Replaces the geometry of the feature with a threedimensional arc whose shape is set by the parameters, which can be either constant floating point values or the values of existing attributes.
Usage Notes
Creating and Modifying Arcs, Circles, and Ellipses
These transformers work with arcs in a variety of ways.

Function 
Geometry Out 
Z Coordinates 

Creates one or more new features with arc geometry (when Geometry Object is an arc type). 
Arc by center point Arc by center point with ends Arc by 3 points Arc by bulge Ellipse (Arc by center point) 
Supported 

Replaces any existing feature’s geometry with a 2D arc. 
Arc by center point 
No 

Replaces any existing feature’s geometry with a 3D arc. 
Arc by center point 
Yes, at center point 

Replaces an existing feature’s geometry with a 2D ellipse or circle (closed arc). 
Ellipse (Arc by center point) 
No 

Modifies an existing arc or converts a point to an arc. 
Arc by center point Arc by center point with ends Arc by 3 points 
Supported, at center and/or ends 

Modifies an existing ellipse (closed arc) or converts a point to an ellipse. 
Ellipse (Arc by center point) 
Supported, at center point 

Extracts the property values that describe an arc’s geometry and stores them as attributes. 
Arc by center point Arc by center point with ends Arc by 3 points Arc by bulge 
Supported 

Extracts the property values that describe an ellipse’s geometry and stores them as attributes. 
Ellipse (Arc by center point) 
Supported 

Converts arcs and ellipses to lines or polygons by interpolating points along the arc. 
Path Line Area 
Supported 

Replaces geometry with an arc described by the first, middle, and last vertices of the input feature. 
Arc by 3 points 
Supported 

Replaces lines or polygons with an optimal combination of line and arc segments, creating smooth curving lines. 
Path Area Arc by bulge Line 
Supported 

Reduces point density on lines or polygons, fitting arcs where possible (When using Algorithm > Douglas With Arc Fitting (Generalize) ). 
Path Area Arc by 3 points Line 
Supported 

Either replaces an existing feature’s geometry with circle that contains all of its vertices or extracts the circle property values into attributes. 
Ellipse (Arc by center point) 
No 
Configuration
Input Ports
This transformer accepts any feature.
Output Ports
Parameters
Center X 
The center x, y, and z parameters set the origin of the arc. 
Center Y 
The center x, y, and z parameters set the origin of the arc. 
Center Z 
The center x, y, and z parameters set the origin of the arc. 
Primary Radius 
The primary and secondary radius set the radii of the arc. Note that the primary radius need not be larger than the secondary, however, the rotation angle is always measured from the x axis to the primary axis. To make a circular arc, set both the primary and secondary radius to the same value. 
Secondary Radius 
The primary and secondary radius set the radii of the arc. Note that the primary radius need not be larger than the secondary, however, the rotation angle is always measured from the x axis to the primary axis. To make a circular arc, set both the primary and secondary radius to the same value. 
Start Angle 
The start angle controls where the arc begins, and is measured in degrees counterclockwise from horizontal. 
Sweep Angle 
The sweep angle controls the duration of the arc, and is measured in degrees. The arc will run from the start angle to the start angle plus the sweep angle. 
Rotation 
The rotation angle is measured in degrees counterclockwise from horizontal, and measures the rotation of the primary axis from horizontal. 
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 dropdown context menu adjacent to the value field.
Using the Text Editor
The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.
Using the Arithmetic Editor
The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.
Conditional Values
Set values depending on one or more test conditions that either pass or fail.
Parameter Condition Definition Dialog
Content
Expressions and strings can include a number of functions, characters, parameters, and more.
When setting values  whether entered directly in a parameter or constructed using one of the editors  strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.
These functions manipulate and format strings.  
Special Characters 
A set of control characters is available in the Text Editor. 
Math functions are available in both editors.  
Date/Time Functions  Date and time functions are available in the Text Editor. 
These operators are available in the Arithmetic Editor.  
These return primarily featurespecific values.  
FME and workspacespecific parameters may be used.  
Creating and Modifying User Parameters  Create your own editable parameters. 
Dialog Options  Tables
Transformers with tablestyle parameters have additional tools for populating and manipulating values.
Row Reordering

Enabled once you have clicked on a row item. Choices include:

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:
Cut, copy, and paste may be used within a transformer, or between transformers. 
Filter

Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer  it does not alter which attributes are output. 
Import

Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers. 
Reset/Refresh

Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers. 
Note: Not all tools are available in all transformers.
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