Filter By Expression TOP node

Conditionally filter upstream work items

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Parameters
Examples

This node evaluates an expression for each upstream work item to determine if the upstream item should be filtered out.

Parameters

Work Item Generation

Whether this node generates static or dynamic work items. You should generally leave this set to "Automatic" unless you know the node’s work items can be computed statically, or that they need to be generated dynamically.

Dynamic

This node always creates dynamic work items: it waits until the upstream work items are known, and generates new work items from the upstream work items.

Static

This node always creates static work items: it creates the number of work items it thinks it needs based on the parameters (and any upstream static items) before the network runs.

Automatic

If the input is static (a static processor, or a partitioner with only static inputs, or a mapper), this node generates static work items, otherwise it generates dynamic work items.

Filter Expression

Evaluated for each upstream work item. When the result is 1/true, the upstream item is filtered out, otherwise the item will be copied by this node.

Include Result Data

When this toggle is enabled result data from the upstream item is includes on the copied work items.

Invert Filter

Inverts the filter so that work items that match are filtered out and items that don’t are copied.

Examples

example_top_filterbyexpression Example for Filter By Expression TOP node

This example demonstrates how to filter upstream workitems so that the remaining set can be further processed or debugged.

The following examples include this node.

example_top_filterbyexpression Example for Filter By Expression TOP node

This example demonstrates how to filter upstream workitems so that the remaining set can be further processed or debugged.

example_top_partitionbycomparison Example for Partition by Comparison TOP node

This example demonstrates how to use the partition by combination node in PDG/TOPs.

See also

TOP nodes

Attribute Copy

Copies attributes from work items in one branch onto work items in another branch.
Attribute Create

Creates or sets an attribute on all incoming work items.
Attribute Delete

Removes attributes from work items.
Attribute from String

Parses attribute values from a string, such as a file name.
Block Begin Feedback

Starts a feedback loop. TOP nodes within the block execute serially, optionally looping for each incoming work item.
Block End Feedback

Ends a feedback loop. TOP nodes within the block execute serially, optionally looping for each incoming work item.
CSV Input

Copies data from a CSV file into work item attributes.
CSV Output

Writes work item attributes to a CSV file.
Command Send

Sends code to a shared server to execute
Command Server End

Ends a command server block.
Deadline Scheduler

PDG Scheduler for Thinkbox’s Deadline software.
Download File

Downloads the contents of one or more URLs into files.
Environment Edit

Edits the variables set in the environment work item command lines execute in.
Error Handler

Error handler for failed work items.
FFmpeg Encode Video

Encodes a sequence of still images as a video file.
FFmpeg Extract Images

Extracts a sequence of still images from a video file.
File Compress

Compress files into an archive.
File Copy

Copies a file from one location to another, either at runtime or whenever the node generates.
File Decompress

Decompresses archive files specified by incoming work items into individual files.
File Pattern

Creates work items based on files that match a certain pattern.
File Remove

Deletes a file at a specified path.
File Rename

Renames or moves a file.
Filter By Expression

Conditionally filter upstream work items
Generic Generator

Generates work items with no attributes that run a command line.
Generic Server Begin

Starts a generic command server.
Geometry Import

Load points or primitives from SOP or file geometry into work item attributes or a temporary file.
HDA Processor

Creates work items that cook a digital asset
HQueue Scheduler

Schedules work items using HQueue.
Houdini Server Begin

Starts a persistent Houdini command server
ImageMagick

Provides easy access to ImageMagick functionality such as mass image convert, resize, and image mosaics.
Invoke

Invokes a compiled block on input geometry
Json Input

Extracts data from JSON files and creates attributes
Json Output

Performs various operations that produce JSON output
Local Scheduler

Schedules work items on the local machine.
Make Directory
Map All

Maps all upstream work items to downstream work items.
Map by Expression

Maps upstream work items to downstream work items using an expression
Map by Index

Maps upstream work items to downstream work items based on their index.
Map by Range

Map upstream work items to downstream work items using range values
Maya Server Begin

Starts a persistent Maya command server
Merge

Merge all upstream work items
Null

Does nothing
OP Notify

Notify an OP node that some TOP work has completed
Output

Subnet output
Partition by Attribute

Partitions work items based on their attributes
Partition by Bounds

Partitions source items spatially using the bounding items.
Partition by Combination

Partitions work items into pairs, triples, etc
Partition by Comparison

Partitions work items using existing comparisons
Partition by Expression

Partitions work items based on an expression
Partition by Frame

Partitions work items based on their frame
Partition by Index

Partitions work items based on their index
Partition by Node

Partitions work items based on their node
Partition by Range

Partition work items based on range values
Partition by Tile

Partitions work items spatially using axis-aligned bounding boxes.
Perforce

Execute Perforce commands through PDG
Python Mapper

Maps work items using a Python script
Python Partitioner

Partitions work items using a Python script
Python Processor

Generate work items using a Python script
Python Scheduler

A Python-based programmable Scheduler for PDG.
Python Script

Creates work items that run a script
ROP Alembic Output

Creates work items that cook an embedded ROP Alembic node
ROP Composite Output

Creates work items that cook an embedded ROP Composite node
ROP Fetch

Creates work items that cook a ROP node or network
ROP Geometry Output

Creates work items that cook an embedded ROP Geometry node
ROP Mantra Render

Creates work items that cook an embedded ROP Mantra node
Render IFD

Creates work items that render an IFD with Mantra
SQL Input
SQL Output
Send Email

Sends an email
Shotgun Create

Create a Shotgun entity.
Shotgun Download

Download an attachment from Shotgun.
Shotgun Find

Find a Shotgun entity.
Shotgun New Version

Create a new Version with an attachment.
Shotgun Session

Start a session to connect to a Shotgun instance.
Shotgun Update

Update fields on an existing Shotgun entity.
Shotgun Upload

Create an attachment in Shotgun.
Sort

Sorts work items by a list of attributes
Split

Splits upstream items in two
Switch

Switch which between network branches
TOP Fetch

Cooks another TOP network
TOP Fetch Input

Input to a TOP fetch-ed network
Text to CSV

Converts some plain text to CSV
Tractor Scheduler

Schedules work items using Pixar’s Tractor.
Wait for All

Waits for all upstream work items to complete.
Wedge

Creates work items with varying attribute values.
Work Item Expand

Expands file lists or partitions into multiple work items
Xml Input

Extracts data from an XML file and creates a string attribute containing the data