Send entire columns at once

The log API is designed to extract data from your running code as it's being generated. It is, by nature, row-oriented. If you already have data stored in something more column-oriented, it can be both a lot easier and more efficient to send it to Rerun in that form directly.

This is what the send_columns API is for: it lets you efficiently update the state of an entity over time, sending data for multiple index and component columns in a single operation.

⚠️ send_columns API bypasses the time context and micro-batcher ⚠️

In contrast to the log API, send_columns does NOT add any other timelines to the data. Neither the built-in timelines log_time and log_tick, nor any user timelines. Only the timelines explicitly included in the call to send_columns will be included.

To learn more about the concepts behind the columnar APIs, and the Rerun data model in general, refer to this page.

Reference

Examples

Updating a scalar over time, in a single operation

Consider this snippet, using the row-oriented log API:

snippet: archetypes/scalars_row_updates

which can be translated to the column-oriented send_columns API as such:

snippet: archetypes/scalars_column_updates

Updating a point cloud over time, in a single operation

Consider this snippet, using the row-oriented log API:

snippet: archetypes/points3d_row_updates

which can be translated to the column-oriented send_columns API as such:

snippet: archetypes/points3d_column_updates

Each row in the component column can be a batch of data, e.g. a batch of positions. This lets you log the evolution of a point cloud over time efficiently.

Updating a fixed number of arrows over time, in a single operation

Consider this snippet, using the row-oriented log API:

snippet: archetypes/arrows3d_row_updates

which can be translated to the column-oriented send_columns API as such:

snippet: archetypes/arrows3d_column_updates

Each row in the component column can be a batch of data, e.g. a batch of positions. This lets you log the evolution of a set of arrows over time efficiently.