FCALGS is a collection of standalone tools implementing algorithms for Formal Concept Analysis (FCA) – a method of qualitative data analysis founded by Rudolf Wille (TU Darmstadt) in mid 80s. Our intention is to implement high-performance command-line tools for computing formal concepts, (frequent) itemsets, nonredundant bases, boolean matrix decompositions, and solving other problems related to the FCA.


All packages come with sources and static precompiled binaries for GNU/Linux and Microsoft Windows operating systems. Supported and tested hardware platforms include i686, x86_64, and sparc64. Each program is individually packaged and documented.

Package Release Date Implementation Download Documentation
IterEss ins 2017/11/29 serial, bitarrays iteress-ins.zip
FCbO ins 2010/10/05 serial, bitarrays fcbo-ins.zip fcbo-ins.html
PCbO amai 2009/03/03 parallel, bitarrays pcbo-amai.zip pcbo-amai.html

All tools in FCALGS use a common set of input/output data formats.

License and Resources

The tools are distributed under the terms of GNU General Public License Version 2.

Users in academia are kindly asked to cite the following resources if the software is used to pursue any research activities which may result in publications:

  1. Outrata J., Vychodil V.: Fast Algorithm for Computing Fixpoints of Galois Connections Induced by Object-Attribute Relational Data.
    Information Sciences 185(1)(2012), pp. 114–127.
    DOI 10.1016/j.ins.2011.09.023, ISSN 0020–0255
  2. Krajca P., Outrata J., Vychodil V.: Advances in algorithms based on CbO.
    In: Kryszkiewicz M., Obiedkov S. (Eds.): Proc. CLA 2010, pp. 325–337.
    CEUR WS, Vol. 672, ISBN 978–84614–4027–6
  3. Krajca P., Outrata J., Vychodil V.: Parallel Algorithm for Computing Fixpoints of Galois Connections.
    Annals of Mathematics and Artificial Intelligence 59(2)(2010), pp. 257–272.
    DOI 10.1007/s10472–010–9199–5, ISSN 1012–2443 (paper), 1573–7470 (online)
  4. Krajca P., Outrata J., Vychodil V.: Parallel Recursive Algorithm for FCA.
    In: Belohlavek R., Kuznetsov S. O. (Eds.): Proc. CLA 2008, pp. 71–82.
    CEUR WS, Vol. 433, ISBN 978–80–244–2111–7