TestFilter

Filters features by test conditions to one or more output ports.

Typical Uses

Replacing multiple Testers
Dividing features into multiple streams

How does it work?

The TestFilter accepts any type of feature and evaluates them against any number of specified tests.

Features are output though a named port when they pass a test, and may be output at the first test they pass or for every test they pass.

Features that do not pass any tests are output as <Unfiltered>.

Creating Test Clauses

Each clause is composed of a value to test, and the method of testing it. Depending on the type of test, at a minimum the clause will consist of a Left Value and an Operator. If the chosen Operator needs more information (for example, testing for an attribute that is greater than a certain value), a Right Value field is provided.

The Test Clauses are created in a table, and numbered from the top down.

Left Value	Operator	Right Value	Mode*
The value or expression to test	The type of test to perform	The value for comparison, if required by the operator	Test the values in a specific manner
Examples
Latitude	>	49.000001	Automatic
@Area()	In Range	(1,100)	Numeric
SnackType	Like	Kebabs	Case Sensitive
Traffic	Attribute Is Null	<Unused>	Automatic
Count	Type Is	Integer	Automatic

* Note that Mode is only available for individual tests when Comparison Mode is set to Specify Per Test.

Test Clause Operators

See all operators

These are the Operators available for constructing test clauses. They may be used to test attribute values, constructed expressions, constants, and published parameters.

Note that (unless otherwise specified) most operators can be used with both numeric values and strings. Strings may be compared with the =, !=, <, >, <=, and >= operators, and are evaluated by their character codes, so A < B.

Operator

Description

Right Value Configuration

Equal to

Enter a value for comparison.

Not Equal to

Enter a value for comparison.

Less than

Enter a value for comparison.

Greater than

Enter a value for comparison.

Less than or equal to

Enter a value for comparison.

Greater than or equal to

Enter a value for comparison.

In Range

Tests if the value falls within the numeric range specified in set notation.

Open-ended ranges may be defined by leaving either the lower or upper limit blank.

Range values are separated by a comma and enclosed by brackets.

Square brackets - [ ] - indicate inclusive limits (greater than or equal to, less than or equal to).

Round brackets - ( ) - indicate exclusive limits (greater than, less than).

Valid range examples:

(1,9) Greater than 1 and less than 9

[1,9] Greater than or equal to 1 and less than or equal to 9

(1,9] Greater than 1 and less than or equal to 9

(1,) Greater than 1

[,9] Less than or equal to 9

Note This operator is not available when Mode is set to Case Sensitive or Case Insensitive, and those modes are not available when the operator is set to In Range.

Tests if the value may be found in the provided list of possible values and ranges.

Enter any combination of comma-separated strings, numeric values, and/or ranges (in the form of x-y).

Valid configuration examples:

1,10,100

1-99

cat

cat,dog,cats and dogs

dogs,1-9,7

String ranges (for example, a-d) can also be specified. To test for values that contain a hyphen, enclose the value in quotation marks: "LL-27","LL-83".

To test for values that contain either single (') or double (") quotes, enclose the value in the opposing quotes: "Duncan's Lake" or 'Say "Hello"'.

Like

Tests that the value matches a specified string pattern.

Enter a string pattern. Wildcards are supported using the percentage symbol (%), rather than an asterisk (*).

In Automatic mode, this operator is case insensitive. This operator is not available when Mode is set to Numeric.

Example:

If Right Value is %bc%:

abcd: Passed

bc: Failed

Contains

Tests that the Right Value occurs somewhere in the Left Value.

Enter a value to test for.

In Automatic mode, this operator is case insensitive. This operator is not available in Numeric mode.

Example:

If Right Value is bc:

abcd: Passed

abde: Failed

Begins With

Tests that the Left Value string begins with the Right Value string.

Enter the string to be tested against.

In Automatic mode, this operator is case insensitive. This operator is not available in Numeric mode.

Example:

If Right Value is Do:

Dogs: Passed

Cats: Failed

Ends With

Tests that the Left Value string ends with the Right Value string.

Enter the string to be tested against.

In Automatic mode, this operator is case insensitive. This operator is not available in Numeric mode.

Example:

If Right Value is gs:

Dogs: Passed

Cats: Failed

Contains Regex

Tests that the value contains a string that matches a pattern described by a Regular Expression.

Enter a Regular Expression.

The Regular Expression Editor is available via the ellipsis (...) button, and may be used to construct and test expressions.

The regex to test may represent a string to be found anywhere within the value, or may represent the entire value (by creating a regex long enough to represent the extent of the desired value).

Example:

If regex is \d (Any digit)

cats: Failed

9: Passed

cats82: Passed

Type Is

Tests if the value is compatible with the chosen Type.

You may test for multiple types by adding additional Test Clauses.

Select the Type to test for.

Boolean	Valid Boolean values are the strings: TRUE, True, true, YES, Yes, yes, 1 FALSE, False, false, NO, No, no, 0
Double	Floating-point number
Integer	Integer
Numeric	A number (same behavior as Double)
Alphanumeric	All characters are either a digit (0-9) or a letter (a-z, A-Z). White space, nulls, control codes, punctuation, and accented or extended characters are not included.
String	A sequence of characters. The value does not contain any null characters.
XML	Checks for valid XML syntax.
JSON	Checks for valid JSON syntax.

Encodable In

Tests if the value is encodable in the specified encoding without data loss.

Select from a list of standard encodings.

Sample encodings:

Unicode 32-bit(utf-32)
Windows Cyrillic (windows-12510
EBCDIC US (ibm037)

Attribute has a value

Tests that the attribute has a value, and is not null, missing, or empty.

Attribute Is Null

Tests that the attribute has a null value.

Attribute is Empty String

Tests that the value is an empty string.

Attribute is Missing

Tests that the attribute is absent on the feature

Cached Values and Data-Aware Test Clauses

If Feature Caching is enabled, valid attribute values from upstream features can be viewed to complete test clauses.

As shown here in the Tester, if the Left Value has been set to an Attribute Value and the features have been cached, the context menu provides access to the values available in those features. If there are only a few choices, they will be presented in a sub-menu.

If there are a large number of choices, the values will be presented in a Select Value dialog, where the values may be sorted and searched with the Filter option.

Connecting Test Clauses: Logic

Multiple test clauses are connected with Logic, using AND, OR, and NOT in addition to parentheses to specify how the tests are evaluated to determine passing or failing.

Logic connectors can be edited by selecting options in the Logic column of the Test Clauses table, or may be edited directly using the Composite Expression parameter’s Edit button.

Configuration

Input Ports

Output Ports

Parameters

Advanced

Preserve Feature Order

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.

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.

Text Editor

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.

Arithmetic Editor

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

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	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:

Add a row
Remove a row
Move current row up one
Move current row down one
Move current row to top
Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

Cut a row - delete and copy to clipboard
Copy a row to the clipboard
Paste a row from the clipboard

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.

Reference

Processing Behavior	Feature-Based
Feature Holding	No
Dependencies	None
Aliases
History

FME Community

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Examples may contain information licensed under the Open Government Licence – Vancouver, Open Government Licence - British Columbia, and/or Open Government Licence – Canada.