Houdini 18.0 Nodes TOP nodes

Filter by Expression TOP node

Conditionally filter upstream work items

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This node evaluates an expression for each upstream work item to determine if the upstream item should be filtered out. The filter can be inverted so that matched work items are kept by setting the Operation parameter to Keep Matched Items.


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.


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.


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.


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.


Determines whether this node should remove any work items that match the Filter Expresion or keep the work items that match the filter

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 Output Files

When this toggle is enabled, output files from the upstream item are included on the copied work items.


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.

See also

TOP nodes