Interchange / GeneralValidated with real files

Apache Arrow / Feather (.arrow / .feather)

.arrow.feather

Apache Arrow, Polars, PyArrow, pandas, DuckDB, and modern high-performance analytics engines

What it is

The standard open-source columnar in-memory and on-disk binary format for high-speed scientific and analytics data interchange. Read directly via the official apache-arrow library.

Who produces it

Data scientists and engineers using Python (Polars, pandas, PyArrow), R (arrow), Julia, Rust, or DuckDB to store columnar datasets without serializing to slow text formats.

What we read / what we don't read

What we read

  • Arrow IPC File format (.arrow, .feather with ARROW1 magic header)
  • Arrow IPC Stream format
  • Numeric columns (Float32/64, Int8..64, Uint8..64) normalized to Float64Array
  • Utf8 and LargeUtf8 string columns
  • Boolean columns normalized to numeric binary flags
  • Date32/Date64 and Timestamp columns normalized to epoch milliseconds (with microsecond and nanosecond unit scaling)

What we don't read

  • Nested List, Struct, Map, and Union columns (skipped to preserve 2D spreadsheet topology)
  • 64-bit integers exceeding 2^53 - 1 (may lose least-significant precision due to JavaScript Number limits)

How to import it into AltaiPlot

  1. Open AltaiPlot and drag your .arrow or .feather file onto the window, or use File → Import.
  2. AltaiPlot detects the Arrow IPC signature and parses columns with zero memory duplication.
  3. Preview the schema and column names.
  4. Click Import to load the columnar data instantly.

Auditability note: this page's capability claims are sourced fromsrc/renderer/src/engine/v7/import/importers/ArrowImporter.ts:45 — see the full format list for every extension AltaiPlot recognizes.