FlowIO

Purpose

Use FlowIO as a lightweight, low-level reader and writer for Flow Cytometry Standard files. Examples in this skill target FlowIO 1.4.0, the current stable release verified on 2026-09-30. Standalone FlowIO checks used Python 3.13, NumPy 2.5.3, and pandas 3.0.6.

FlowIO is appropriate for:

• Reading FCS 2.0, 3.0, and 3.1 files
• Inspecting HEADER, TEXT, ANALYSIS, and channel metadata
• Retrieving event data as a two-dimensional NumPy array
• Reading legacy files that contain multiple datasets
• Writing list-mode, single-precision FCS 3.1 files
• Preparing data for pandas, machine-learning, or downstream cytometry tools