ChangeDetector

Detects changes between two sets of input features.

This transformer is often used with multiple readers, to identify changed features in the two files. It can identify all features that two input files have in common, and those which are in one file and not the other, such as the additions and the deletions.

Usage Notes

  • The Matcher provides a more general approach, which may be more convenient for certain applications.
  • Oriented points are supported, however, precision loss when converting between orientation representations will often cause the ChangeDetector and Matcher to identify two oriented points as Updated/NotMatched unless Lenient Geometry Matching is enabled.

Configuration

Input Ports

Output Ports

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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