[GAP Forum] List of available functions

[Alexander Konovalov]

Dear Timothy, dear Forum,

On 10 Nov 2010, at 19:46, Ivan Andrus wrote:

> Perhaps GLOBAL_FUNCTION_NAMES is what you are looking for.
> 
> -Ivan Andrus
> 
> On Nov 9, 2010, at 3:52 AM, Timothy Murphy wrote:
> 
>> I once brought up a list of available functions in GAP,
>> but have forgotten what command I gave.
>> Could some kind soul remind me, please.
>> (I'm mainly interested in functions related to groups.)

In addition to Joe's reference to the HTML version of the manual
(which is not only available on the GAP website, but is also a
part of a GAP installation), I would recommend using the search 
facilities of the GAP help system as the best way to get an 
overview of the functionality related with groups. 

Entering ??group at the GAP prompt will result in this:

gap> ??group
Help: several entries match this topic - type ?2 to get match [2]

[1] polycyclic (not loaded): Group
[2] RCWA (not loaded): Group
[3] Tutorial: Groups and Homomorphisms
[4] Tutorial: Permutation groups
[5] Tutorial: Actions of Groups
[6] Tutorial: Subgroups as Stabilizers
[7] Tutorial: Group Homomorphisms by Images
[8] Tutorial: Further Information about Groups and Homomorphisms
[9] Tutorial: group general mapping
[10] Tutorial: GroupHomomorphismByImages vs. GroupGeneralMappingByImages
[11] Tutorial: group general mapping single-valued
[12] Tutorial: group general mapping total
[13] Reference: Free Groups, Monoids and Semigroups
[14] Reference: FreeGroup
[15] Reference: Rewriting in Groups and Monoids
  -- <space> page, <n> next line, <b> back, <p> back line, <q> quit --

and (for my particular GAP installation) this ends up with more than a 
thousand entries, including also those from GAP packages manuals:

...
[1180] RCWA (not loaded): GeneratorsAndInverses for a group
[1181] RCWA (not loaded): EpimorphismByGenerators for two groups
gap>        

Note that GLOBAL_FUNCTION_NAMES is an undocumented internal variable 
(as its name in uppercase with underscores suggests). Moreover, it 
does not contain GAP operations, as you can see from the following 
convincing example:

gap> ConjugacyClasses;
<Operation "ConjugacyClasses">
gap> "ConjugacyClasses" in GLOBAL_FUNCTION_NAMES;
false

so it will not give you the full picture (unless you are specifically
interested in the list of *functions* and not operations).

Best regards,
Alexander