fcswrite

library0.6.4pypypi✓ verified 85d ago

A lightweight library for writing Flow Cytometry Standard (FCS) files from Python. Current version 0.6.4, requires Python >=3.6. The library is in maintenance mode with infrequent releases.

data

pip install fcswrite

github ↗package ↗changelog ↗

INSTALL

IMPORT

SIG · FCSWRITE

fcswrite

datapythonv0.6.4

Install

3.5s avg

Import

278ms

Disk

89MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.6.4 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.274s · 89.4MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 3.5s · import 0.282s · 86MB

89MB installed

● package 89MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

fcswrite

✓ from fcswrite import fcswrite

✗ import fcswrite

fcswrite is a module, not a package; the correct import is 'from fcswrite import fcswrite' to get the write_fcs function.

Minimal example to write an FCS file with two channels and three events.

from fcswrite import fcswrite import numpy as np # Create some data (events x channels) data = np.array([[1, 2], [3, 4], [5, 6]], dtype=np.float32) # Channel names chnames = ['FSC', 'SSC'] # Write FCS file fcswrite.write_fcs('test.fcs', chnames, data) print('FCS file written successfully.')

Debug

Known issues

gotchaThe function is named 'write_fcs' but must be accessed via 'fcswrite.write_fcs' after 'from fcswrite import fcswrite'.

fix

Use: from fcswrite import fcswrite; fcswrite.write_fcs(...)

affects: all

gotchaThe library does not support writing FCS 3.0 or later versions; it only writes FCS 2.0 files.

fix

For FCS 3.0+ support, consider other libraries like 'flowio' or 'fcsy'.

affects: all

Errors

Common errors & fixes

AttributeError: module 'fcswrite' has no attribute 'write_fcs'

Incorrect import: using 'import fcswrite' instead of 'from fcswrite import fcswrite'

fix

Use: from fcswrite import fcswrite

TypeError: write_fcs() missing 1 required positional argument: 'data'

Calling write_fcs without all required arguments (filename, chnames, data).

fix

Provide all three positional arguments: write_fcs('output.fcs', ['FSC','SSC'], data_matrix)

Upgrade

Version history

0.6.4latest on PyPI · released Nov 9, 2025

Audit

Dependencies

No dependency data recorded yet.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/DC-analysis/fcswrite ↗

packagehttps://pypi.org/project/fcswrite/ ↗

changeloghttps://raw.githubusercontent.com/DC-analysis/fcswrite/refs/heads/master/CHANGELOG ↗