FME Transformers: 2024.1
FME Transformers: 2024.1
TimeWindower
Adds a time window attribute to each feature, assigning a Window ID based on either the time the feature arrives at the transformer or a timestamp stored as an attribute.
The duration of a time window is specified with a choice of units (seconds, minutes, hours, or days), and the first window may commence at workspace startup, with the arrival of the first feature, or at a specified timestamp.
The Window ID value may be either:
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an incremental count of windows (based on the specified duration, starting with zero (0)), or
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the start or end time of the window (in seconds, Unix time).
Configuration
Output Ports
Output
Features that successfully have the Window ID attribute added to the feature.
All features exit via this port unless:
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the feature is rejected, or
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an Order Type is selected and the feature is outside of the current window
WindowChanged
When the Window ID attribute changes, a new feature is created and sent out of this port.
This new feature leaves the WindowChanged port before any features in that window are sent out of the Output port.
OutOfSequence Features are output here if the data entering the TimeWindower is sequenced and a feature’s timestamp is outside of the current window and window tolerance.
Note This transformer does not sort the features through time. If the features entering the transformer are not ordered then the same window changed feature could be output more than once.
OutOfSequence
This port is only exposed if the time window is based on the value of an attribute.
Features are output through this port if their timestamp does not line up with the current time window and the tolerance interval for the window it belonged to has ended.
<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
Window Definition
Window Duration |
The window duration in units specified by the Time Units parameter. |
Time Units |
The units for the window duration.
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Time Window Starts |
Defines when the first window initiates.
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At Timestamp |
User specified timestamp for the first window. This parameter is enabled when At Timestamp is selected for the Time Window Starts parameter. |
Timestamps
Data Has Timestamps |
Determines how features entering the transformer are assigned to a window. If set to No (Default), then the features are assigned to the window from the current processing time. If set to Yes, then the Timestamp Attribute is used for window assignment. |
Timestamp Attribute |
The timestamp to be evaluated and used to assign the feature to a window. It must be a valid FME Date/Time. This parameter is enabled when the Data Has Timestamps parameter is Yes. |
Output Attribute Name
Window ID Attribute
Name the attribute to contain the window id. The type of id is specified by ID Type.
ID Type
Specifies the window id type.
- Window Start Time (Default): The start time of an assigned window in seconds since the start of the Unix epoch, 00:00:00 UTC on 1 January 1970. Window start time before this date are in negative seconds.
- Window End Time: The end time of an assigned window in seconds since the start of the Unix epoch, 00:00:00 UTC on 1 January 1970. Window end time before this date are in negative seconds.
- Window Number: An integer count for the assigned windows. The count starts at 0 and it is assigned to the first window. The number may also be negative, -1 is assigned to the window before the first window.
Window ID Attribute |
Name the attribute to contain the window id. The type of id is specified by ID Type. |
ID Type |
Specifies the window id type.
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Order Settings
Specifies the time order that the data is expected to arrive at the transformer. This is only useful when a Timestamp Attribute is specified.
Order Type |
Enforces the order of the features through the output port. Features that did not follow the specified ordering will be sent to the OutOfSequence port.
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Tolerance Settings
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Enabled when Order Type is Chronological or Reverse Chronological.
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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
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Enabled once you have clicked on a row item. Choices include:
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Cut, Copy, and Paste
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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
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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
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Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers. |
Reset/Refresh
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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.
FME Community
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