Shortens the geometry of a line feature from the ends by snipping specified distances, indices, or measure values. It operates on features with simple line geometry and polygons without holes.
The parameters specify a starting and ending point for the snipping. After execution, the feature's geometry will be a line representing the portion of the original line between those two positions, inclusive of the endpoints. New coordinates will be generated at the beginning or end of the line, if there are not already coordinates at exactly the specified positions. If the line contains three-dimensional coordinates, the Z value at each endpoint will be interpolated linearly from the original feature's coordinates between which the endpoint exists.
Example
Using measures in Snipping Mode
Suppose you have a line with measures that range from 4 to 16. The Starting Location has the value 6 and the Ending Location has the value 8.
If the Snipping Mode is Measure (Value), the resulting feature would have measures that range from 6 to 8.
If the Snipping Mode is Measure (Relative to Start Point), the resulting feature would have measures that range from 10 (= 4 + 6) to 12 (= 4 + 8).
Configuration
Input Ports
Input
Features with polygon or line geometries are accepted. Aggregate features will be accepted if the Aggregate Handling parameter is Deaggregate.
Output Ports
Output
Features with the shortened geometries are output through this port.
Remnants
Features with the removed portions of the original geometries are output through this port.
<Rejected>
Features without polygon or line geometries (for example, points and donut polygons) are output through this port. Aggregate features will be rejected if the Aggregate Handling parameter is Reject.
Parameters
General
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Aggregate Handling |
Choose how aggregate geometries are to be handled. Deaggregate: Decompose aggregates into their individual components. Reject: Do not process aggregates and output them via the <Rejected> port. |
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Snipping Mode |
Distance (Value) or Distance (Percentage): The amount to snip from the beginning and end of the line can be specified as either a measurement in ground units or a percentage of the line's entire length, starting from the first coordinate. A negative value specifies the final vertex on the line. Values larger than the measurement of the original line will be interpreted as the end point. Each of these parameters may either be entered as a number, or can be taken from the value of a feature attribute by selecting the attribute name from the pull-down list. If the Measurement Mode is 3D, and the linear feature has Z coordinates, all measurements will be taken as a distance from one vertex to the next in 3D space. Otherwise, only the X and Y coordinates will be considered, and measurements will be planar distances between vertices. Measure (Relative to Start Point): The values specified in the Starting Location and Ending Location parameters refer to the absolute difference in the measure value of the start point of the original line and the start or end points of the resulting line respectively. Negative values will be interpreted as the start point of the original line and values larger than the measurement of the original line will be interpreted as the end point. If the Measure Name field is blank, the default measure values are used. Otherwise, the measure values with the name specified in the Measure Name field are used instead. Measure (Value): The values specified in the Starting Location and Ending Location parameters refer to the measure values at the start and end points of the resulting line. Any value less than the input’s starting measure will be interpreted as the start point of the original line and values larger than the input’s ending measure will be interpreted as the end point of the original line. If the Measure Name field is blank, the default measure values are used. Otherwise, the measure values with the name specified in the Measure Name field are used instead. Vertex: The vertices from the original line which are to form the first and last vertices of the resulting line are specified as a numeric index, with "0" being the first vertex of the line. Negative numbers measure vertices relative to the last point in the line, with the value "-1" used to specify the vertex which is the last vertex of the line's geometry, "-2" the second last vertex, and so on. If the input vertex number is smaller than the negative absolute value of the total number of vertices, then it will be interpreted as the starting vertex of the original line and if it is larger than the total number of vertices, it will be interpreted as the ending vertex. Each of these parameters may either be entered as a number, or can be taken from the value of a feature attribute by selecting the attribute name from the pull-down list. |
Measurement
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Measurement Mode |
Choose how Z coordinates are handled. This parameter does not have any effect on two-dimensional lines. This parameter is enabled when the Snipping Mode is Distance (Value) or Distance (Percentage). 2D: Only X and Y coordinates are considered. 3D: If the linear feature has Z coordinates, all measurements will be taken as a distance from one vertex to the next in 3D space. |
Distance, Percentage, or Measure Values
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Starting Location |
The value used to determine the start of the resulting line when the Snipping Mode is Distance (Value), Distance (Percentage), Measure (Relative to Start Point), or Measure (Value). |
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Ending Location |
The value used to determine the end of the resulting line when the Snipping Mode is Distance (Value), Distance (Percentage), Measure (Relative to Start Point), or Measure (Value). |
Measure Name
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Measure Name |
The measure values with the specified name are used when the Snipping Mode is Measure (Relative to Start Point) or Measure (Value). If this parameter is blank, the default measure values are used. |
Indices
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Starting Vertex |
The vertex from the original line which is to form the first vertex of the resulting line specified as a numeric index, with "0" being the first vertex of the line. This parameter is enabled when the Snipping Mode is Vertex. |
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Ending Vertex |
The vertex from the original line which is to form the last vertex of the resulting line specified as a numeric index, with "0" being the first vertex of the line. This parameter is enabled when the Snipping Mode is Vertex. |
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.
How to Set Parameter Values
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.
Content Types
| These functions manipulate and format strings. | |
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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 feature-specific values. | |
| FME and workspace-specific parameters may be used. | |
| Creating and Modifying User Parameters | Create your own editable parameters. |
Dialog Options - Tables
Transformers with table-style parameters have additional tools for populating and manipulating values.
Table Tools
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Row Reordering
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Enabled once you have clicked on a row item. Choices include:
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Cut, Copy, and Paste
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Enabled once you have clicked on a row item. Choices include:
Cut, copy, and paste may be used within a transformer, or between transformers. |
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Filter
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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. |
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Import
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Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers. |
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Reset/Refresh
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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.
FME Community
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Keywords: DistanceSnipper VertexSnipper