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How to cite GAP or its package?

Is may be well-known that there is a page on the GAP website which suggests how to cite GAP.

Perhaps less known is the fact that GAP installation has a file called CITATION, situated in the GAP root directory. This file contains sample citations for this particular version of GAP in text, HTML, BibXML and LaTeX formats.

However, it may be even less known that since GAP 4.7.2 release (December 2013), GAP also provides a function Cite(), which is documented here. Called without arguments, it generates sample citations for GAP in all formats mentioned above. If it is called with the optional string pkgname which contains a name of a GAP package, it produces instructions on citing this package (only if its working version is available in this GAP installation).

It is a good practice to specify the version of the software used in the paper, so this functionality should help to keep it accurate!


Ten hints for GAP beginners


  1. Remember that GAP is case-sensitive! That means that ABC, Abc and abc are three different identifiers. A call to SymmetricGroup(3) works, but Symmetricgroup(3)will cause an error.
  2. An error message “Error, Variable: 'FuncName' must have a value” in a function call usually points to a typo in the function name (see the previous hint), or to some package that must be loaded in advance using LoadPackage.
  3. Do not hesitate to use longer and more informative variable names where appropriate. For example, x looks perfectly suitable for List([1..10], x -> x^2), while ConClassesReps may be more informative than just x for a list of representatives of conjugacy classes of a group.
  4. Use command line editing: scroll the history of commands and navigate within the command line using arrow keys.
  5. Use autocompletion instead of typing names of functions and variables in full. Type the initial part of the identifier and then press <Tab>. It will be autocompleted if its unique completion is possible. If not, you may press <Tab> again to see all possible suggestions.
  6. To view help pages, use ? and ?? commands. This will search not only in the GAP manuals, but also in the manuals of all GAP packages available in your GAP installation.
  7. Set default help format to HTML. Use SetHelpViewer function to view it with your preferred browser.
  8. Use LogTo function to save all GAP input and output into a text file. It should be called before calculations, not after!
  9. If calculation takes too long, press <Control>-C to interrupt it. Then type quit; to leave the break loop.
  10. Read A First Session with GAP from the GAP Tutorial.