Overview

Fityk [fi:tik] is for peak fitting.

Longer version: fityk is a program for nonlinear fitting of analytical functions (especially peak-shaped) to data (usually experimental data). There are also people using it to remove the baseline from data, or to display data only.

It is reportedly used in crystallography, chromatography, photoluminescence and photoelectron spectroscopy, infrared and Raman spectroscopy, to name but a few.

Fityk knows about common peak-shaped functions (Gaussian, Lorentzian, Voigt, Pearson VII, bifurcated Gaussian, EMG, Doniach-Sunjic, etc.) and polynomials. It also supports user-defined functions.

Fityk offers intuitive graphical interface (and also command line interface), variouse optimization methods (standard Marquardt least-square algorithm, Genetic Algorithms, Nelder-Mead simplex), equality constraints, modelling error of x coordinate of points (eg. zero-shift of instrument), handling series of datasets, automation of common tasks with scripts, and more.

It is a portable (Linux, FreeBSD, MS Windows, MacOS X) and free software (GPL).

Both graphical and command line interfaces use libfityk library. The library is written in C++, and comes with Python bindings.

Xylib library is used for reading data files.

Download

Source code: fityk-0.8.9.tar.bz2
MS Windows Installer: fityk-0.8.9-setup.exe
Fresh Linux RPMs from OBS. Good Linux distros and FreeBSD ports also have fityk packaged.
A bit old MacOSX universal binary (ver. 0.8.2) compiled by Ken McIvor. Read more in the wiki.
Older versions of the program
Daily builds
The latest code: svn co https://fityk.svn.sourceforge.net/svnroot/fityk/trunk fityk

New version notifications:

e-mails from http://freshmeat.net/projects/fityk/
RSS feeds from SourceForge

History

2009-08-20 Version 0.8.9
2009-06-21 Version 0.8.8 (no Windows exe this time)
2009-06-11 Version 0.8.7
2008-04-15 Version 0.8.6

See the full history (and what’s new in each release) in the NEWS file.

Documentation

The manual (PDF) documents mostly commands of the fityk mini-language.

Trac Wiki contains all other informations. You are also welcome to contribute.

Questions or comments?

Join the Google group fityk-users. You may select option “no mail” when joining and use the web interface to read and send messages. Feel free to send there questions, comments, bug reports, feature ideas or success stories.

Asking for a new feature usually results in adding the request to the TODO list or, if it is already on the list, in assigning higher priority to it.

If for some reasons you do not want to use the group, you may contact directly the maintainer of the program: Marcin Wojdyr wojdyr at gmail.com