Houdini 17.5 Nodes TOP nodes

Partition by Range TOP node

Partition work items based on range values

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Parameters

Use Dynamic Partitioning

When this toggle is enabled the partitioner will wait for all input work items to be generated before partitioning them. If the input work items are dynamic, this means the partitioner will have to wait for and depend on the parent(s) of those items.

Merge Input Attributes

When this toggle is enabled the partitioner will merge the attributes of the work items in each partition and export them to the partition itself.

Range

Range Type

Determines how the work item range is specified.

Custom

Custom range based on a ratio of upstream items to partition count and an offset in the left/right directions.

Fixed Count

Creates a fixed number of partitions no matter how many upstream work items there are. Upstream items are distributed as evenly as possible amongst the partitions. If the items don’t divide evenly, the first few partitions will have an extra work item.

Fixed Size

Creates partitions of a fixed size when possible. If the upstream items don’t divide evenly, only the last partition will have the wrong size. It will contain whatever items are left after dividing the upstream items into groups of the desired fixed size.

First/Last

Creates exactly two partitions. The first one contains the first work item from each of the input nodes, and the second partition contains the last work item from each of the input nodes. Other upstream items are not partitioned.

First/Middle/Last

Create exactly three partitions. Behaves the same as the First/Last range type, except the middle work items from each input node are also put into a partition.

Custom Range

These parameters configure the behavior of the partitioner when the Custom Range type is selected. The range is determined by two main properties: the ratio of upstream work items to partitions, and an offset in the left and right direction.

For example, with Upstream Range set to 2 and Partition Range set to 1, one partition will be created for every two upstream work items.

Upstream Range

Along with the Partition Range parameter, determines the ratio between upstream work items and partitions

Partition Range

Determines the number of partitions to create, along with the Upstream Range parameter.

Left Offset

The number of additional items proceeding the selected items that should also be included in the partitions.

Right Offset

The number of additional items that follow the selected items that should also be included in the partitions.

Fixed Count

Range Count

The number of partitions that will be created.

Fixed Size

Range Size

The number of upstream items that will be added to each partition.

Advanced

These are advanced parameters that provide finer control over the behavior of the partitioner.

Auto Remove Stale Dependencies

When recooking the node, indicates that the partitioner should remove old dependencies if the partitioning scheme changes as a result of the cook.

Force Re-Evaluation on Cook

Forces the partitioner to re-evaluation the partitioning scheme even if all of the work items are already cooked and no new work items have been added.

Dirtying Mode

The dirty mode parameter offers fine grained control over when a partition is dirtied and the effects on child items when that occurs. This parameter is particularity useful for working around some of the limitation of using dynamic partitioning.

Standard

A given partition will be dirtied when any of the work items in the partition are dirtied. In the case of dynamic partitioning, if any ancestor of a dynamic work item in a partition is dirtied, then All partitions will be dirtied.

When a partition is dirtied all of its children are deleted.

Non-destructive

The same dirtying behavior as Standard, except when a partition is dirtied its children will be dirtied instead of deleted.

Mapping Standard

A given partition will only be dirtied if an item in the partition is dirtied or if the partition’s contents changes as a result of a recook. When the partition is dirtied, any child work items will be deleted.

Mapping Non-destructive

The same as Mapping Standard, except when a partition is dirtied its children will be dirtied instead of deleted.

Sort Contents By

Determines the order that work items are sorted when accessing the partitions on this node. This also affects the sort order of output files on the partition.

None

No sorting is applied - the work items in the partition are handled in no particular order.

Work Item Index

Work items in the partition are sorted based on their index

Input Node Order

Work items in the partition are sorted based on the order of inputs nodes wired into the partitioner itself. If two work items are from the same input, they are then sorted by index.

Attribute

Work items in the partition are sorted based on the attribute specified in the Sort Attribute parameter.

Sort Direction

Determines whether the work items in this node’s partitions are sorted in ascending or descending order.

Sort Attribute

When Sort Contents By is set to Attribute, this parameter is used to determine the name of the attribute to sort by.

Partition When

This parameter is only enabled when using dynamic partitioning. It controls when the partitioning step is performed on the input work items.

Input Items Are Generated

Inputs are partitioned once all of them have been generated.

Input Items Are Cooked

Inputs are partitioned once all of them are cooked. This is required when the partitioning scheme is based on the results of the work items' execution.

This makes this partitioner behave like a Wait for All except that it may create multiple partitions.

Partition Target

This parameter is only enabled when using dynamic partitioning. When the target is set, the partition scheme will be applied to the work items in the target TOP node instead of the input work items.

The target TOP node must be a processor in the same graph above this node, and there cannot be any other mappers or partitioner between this node and the target.

Examples

example_top_partitionbyrange Example for Partition by Range TOP node

This example demonstrates the multiple partition options provided by the partition by range node.

The following examples include this node.

example_top_partitionbyrange Example for Partition by Range TOP node

This example demonstrates the multiple partition options provided by the partition by range node.

See also

TOP nodes