DuplicateFilter
Detects duplicate features based on the value of one or more key attributes.
Output Ports
This transformer outputs to the Duplicate port any feature whose key attribute value is the same as one previously encountered. Any feature whose key value has not yet appeared is output via the Unique port.
The first feature with a unique key value is output via the Unique port – and subsequent features that have the same key value are output via the Duplicate port.
Parameters
Specify one or more attributes to use for the key attribute. If more than one attribute is specified, the collective value of those attributes forms the key.
Specifies if the current feature should be compared against all previous features, or if it should only be compared against the feature that is immediately before it. If the input data is ordered so that all duplicates are grouped together, set this value to Yes for increased performance.
Advanced
This parameter controls the order in which features exit a transformer.
When a transformer has more than one output port, features usually exit one port at a time. At times, it may be useful to keep the order that features arrived in, switching from port to port as necessary. This allows feature order to be preserved, though at a potential cost in processing efficiency.
Select a method for feature ordering.
Per Output Port (Default) |
Only preserve the input order of features as they occur within the group of features exiting a given output port. All features exiting an output port retain their ordering relative to each other (within the group), but not relative to features exiting other output ports. This option is generally the most efficient, where large chunks of features will exit an output port together (taking advantage of bulk mode). As features exiting different output ports may not be strictly output in the order they arrived, output ordering may be unpredictable. |
Across Output Ports |
Strictly preserve the input order of features, regardless of which output port they exit. Features will be output singly in the same order they arrived, switching from port to port as necessary. This option is generally less efficient as the processing gains of bulk mode are less likely to apply - however, feature order is predictable. |
Usage Notes
- This is a more specific type of operation than that provided by the Matcher, which can match on multiple attributes as well as geometry. For such situations, this transformer is dramatically more efficient than the Matcher.
- Output feature order may be controlled with the Advanced > Preserve Feature Order parameter.
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.
Transformer Categories
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