ChangeDetector
Detects changes between two sets of input features.
这个变压器 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.
Input Ports
One set of features enters the transformer via the原版的port.
Another set of features enters via the修订port.
Output Ports
An原版的feature is output via the不变port when it is found to have either matching geometry, matching attribute values, or both, with a feature in the修订set.
A修订feature with no match in the原版的set is output via the添加port.
An原版的feature is output via the已删除port when no match for it can be found in the修订set.
Parameters
This parameter controls whether 2D or 3D (or None) geometry must be the same before a match is declared.
FULL makes sure 3D, measures, and Geometry Attributes all match.
When comparing raster geometries: 2D matches the properties, 3D matches the properties and values, and FULL matches the properties, values and geometry traits.
When comparing surface and solid geometries: 2D behaves the same way as 3D, that is, z values will also be compared.
If this parameter is set to Yes, then the order of points in area features will be ignored.
Composition differences between paths and lines will be ignored.For example, consider two lines, each with 10 vertices: One line is a path composed of 3 segments, and the other is just a simple line.These lines are considered to have a different composition.Lenient geometry matching will treat all these as matching, as long as they have the same vertices (no more and no less).Strict geometry matching will say they do not match.
True arcs and ellipses versus their stroked polygon equivalents will be ignored in Aggregates, Polygons, Donuts, Paths, and all other multis.
This transformer does not support surfaces or solids in the input if this parameter is set to Yes.
In conjunction with Selected Attributes, this parameter controls which attributes of input features must have the same value before a match is declared.
- 匹配来选择属性:在所选属性参数指定的属性将被匹配。
- 匹配除了选定属性:所有属性都会被匹配,除了那些在所选属性指定。
使用此选项,匹配仅在已公开的属性进行(与所选择的属性可见选择列表)。其结果是,以对所有属性匹配除了未曝光的格式属性,选择这个选项并将所选属性参数为空。 - 匹配所有属性:所有属性都会被匹配,包括未曝光的格式属性。
This parameter is applicable when属性匹配策略is set to匹配来选择属性or匹配除了选定属性, and specifies which attributes to match, or exclude from the match, depending on the matching strategy chosen.
If this parameter is set to没有, then empty, missing, and null attributes will be treated as equivalent.If this parameter is set to是, then empty, missing, and null attributes will be considered as pairwise different.This parameter applies to attributes as well as几何特征.
没有te: This parameter has no effect when using lenient geometry matching.
When geometry is being matched,额外的顶焦度允差can allow for extra vertices along line segments.
A value of 0 means that no such extra vertices are permitted.A nonzero value controls how close any extra vertices must be to the line connecting the adjoining matching vertices.
For surface and solid geometries, Extra Vertex Tolerance is ignored and assumed to be 0.0.
Example
Related Transformers
The ChangeDetector may require a significant amount of processing time, depending on the number of features and/or attributes.Alternatively, consider using theCRCCalculatorto calculate a CRC value for each feature, then perform a match only on the CRC value attribute.
TheMatcherprovides a more general approach, which may be more convenient for certain applications.
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, clickbeside the applicable parameter.For more information, seeTransformer Parameter Menu Options.
Transformer Categories
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