FME Transformers: 2024.2
Categories and Related Transformers
Categories
Attributes
Copies the attributes of the list element specified by the index to become main attributes of the feature.
Example
If this feature enters this transformer:
somelist{0}.length = 7.3
somelist{0}.kind = ’paved’
somelist{1}.length = 8.4
somelist{1}.kind = ’smooth’
somelist{1}.lanes = 2
somelist{2}.length = 1.1
somelist{2}.kind = ’rough’
and the index is set to 2, then the feature leaving the transformer will have these attributes:
length = 1.1
kind = 'rough'
somelist{0}.length = 7.3
somelist{0}.kind = paved
somelist{1}.length = 8.4
somelist{1}.kind = 'smooth'
somelist{1}.lanes = 2
somelist{2}.length = 1.1
somelist{2}.kind = 'rough'
The index 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.
Configuration
Output Ports
Note Feature order may change in relation to other output ports. Feature order per port is maintained.
<Rejected> (Dynamic)
The dynamic <Rejected> port appears when a parameter is set to a non-literal value that might make processing impossible.
For example, if a numeric parameter such as Line Width, Count Start, or Decimal Places is set to an expression, attribute value, or user parameter, it is possible to pass in a non-numeric value that cannot be used. Decimal Places = Cat cannot be processed, so the feature will be output via this port.
Rejected features will have an fme_rejection_code attribute explaining the reason for rejection.
Rejected Feature Handling: can be set to either terminate the translation or continue running when it encounters a rejected feature. This setting is available both as a default FME option and as a workspace parameter.
Parameters
General
|
List Attribute |
Specifies the name of the list attribute the transformer will read from. |
|
List Index To Copy |
The index of the list element whose contents will be copied to the main attribute(s) of the output feature. If you enter a negative number, the index starts from the back of the list (for example, -1 will copy the last element in the list). |
|
Copied Attribute Prefix |
An optional prefix that is added to the demoted attributes. |
|
Copied Attribute Suffix |
An optional suffix that is added to the demoted attributes. |
Editing Transformer Parameters
Transformer parameters can be set by directly entering values, using expressions, or referencing other elements in the workspace such as attribute values or user parameters. Various editors and context menus are available to assist. To see what is available, click 
beside the applicable parameter.
How to Set Parameter Values
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.
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. | |
|
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
Table Tools
Transformers with table-style 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.
For more information, see Transformer Parameter Menu Options.
Additional Resources
FME Community
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