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Arrow extension for WarpScript

WarpScript functions for conversions from and to Apache Arrow columnar format.

From WarpScript to Arrow

->ARROW    // Encode input into Arrow columnar format (BYTES).

The supported input types are described in the conversion table below. The output is a BYTES representation of an Arrow table, containing a map of metadata and columns. The arrow metadata will contain the fields WarpScriptConversionMode, WarpScriptVersion and WarpScriptTimeUnitsPerSecond.

Input description Output description Metadata description WarpScriptConversionMode
List of GTS encoders or GTS one column for classname, one per label key, one for timestamp, one for latitude, one for longitude, one for elevation, one per value type no additional output metadata ENCODERS
A GTS one column for timestamp, one for latitude, one for longitude, one for elevation, one for value output metadata includes full GTS metadata GTS
A pair list containing a map of metadata and a map of lists of equal size one column per list the input map of metadata is the output metadata PAIR

Empty columns are not encoded.

From Arrow to WarpScript

ARROW->    // Decode an Arrow stream (BYTES).

The function will try to infer the type of the result using the value of the metadata WarpScriptConversionMode, based on the conversion table above. If the input has no WarpScriptConversionMode, it will use the default WarpScriptConversionMode PAIR.

NOTE

We made a blog article to present this extension: https://blog.senx.io/conversions-to-apache-arrow-format/

Build notes

Depends on rev >= 2.2.0