[GAP Forum] IsomorphismTypeFiniteSimpleGroup results in an error.

buynnnmmm1 at yahoo.co.jp buynnnmmm1 at yahoo.co.jp
Mon Sep 15 12:41:26 BST 2014


Thank you very much for e-mail immediately.
Thank you very much for your help.
I was sure that even here can do it.

gap> s8:=Group((1,2),(1,2,3,4,5,6,7,8));
Group([ (1,2), (1,2,3,4,5,6,7,8) ])
gap> a8:=CommutatorSubgroup(s8,s8);
Group([ (1,3,2), (2,4,3), (3,5,4), (4,6,5), (5,7,6), (6,8,7) ])
gap> elab:= Group( (1,2)(3,4)(5,6)(7,8), (1,3)(2,4)(5,7)(6,8),  (1,5)(2,6)(3,7)(4,8));
Group([ (1,2)(3,4)(5,6)(7,8), (1,3)(2,4)(5,7)(6,8), (1,5)(2,6)(3,7)(4,8) ])
gap> norm:= Normalizer( a8, elab );;
gap> hom:=NaturalHomomorphismByNormalSubgroup( norm , elab );
<action epimorphism>
gap> f := Image( hom );
Group([ (), (), (), (4,5)(6,7), (4,6)(5,7), (2,3)(6,7), (2,4)(3,5), (1,2)(5,6) ])
gap> IsomorphismTypeInfoFiniteSimpleGroup( f );
rec( name := "A(1,7) = L(2,7) ~ B(1,7) = O(3,7) ~ C(1,7) = S(2,7) ~ 2A(1,7) = U(2,7) ~ A(2,2) = L(3,2)", parameter := [ 2, 7 ], 
  series := "L" )

I've read http://www.gap-system.org/Manuals/doc/ref/chap77.html.
Then, Http://www.math.niu.edu/help/math/gap4/ref/CHAP036.htm was hit when I net doing a keyword search for "IsomorphismTypeFiniteSimpleGroup".

I was Written in the document with the "GAP 4 manual February 2000". 
It seems there was IsomorphismTypeInfoFiniteSimpleGroup function in GAP4 of the old version.

This document, because it is updated on 2014/8/16 recently, I think the document author and not using "GAPDoc package". 
I leave the mail also "GAPDoc package" to the author.


Thank you very much for your help!

P.S.
I resend same e-mail because I've forgotten cc column of mail (forum at gap-system.org).

                   buynnnmmm1




----- Original Message -----
> From: Alexander Konovalov <alexk at mcs.st-andrews.ac.uk>
> To: buynnnmmm1 at yahoo.co.jp
> Cc: "forum at gap-system.org" <forum at gap-system.org>
> Date: 2014/9/15, Mon 18:25
> Subject: Re: [GAP Forum] IsomorphismTypeFiniteSimpleGroup results in an error.
> 
> Hello,
> 
> The correct name of this function is IsomorphismTypeInfoFiniteSimpleGroup. Using 
> the input from the question, it produces the expected result:
> 
> gap> IsomorphismTypeInfoFiniteSimpleGroup( f );
> rec( name := "A(1,7) = L(2,7) ~ B(1,7) = O(3,7) ~ C(1,7) = S(2,7) ~ 2A(1,7) 
> = U(2,7) ~ A(2,2) = L(3,2)", parameter := [ 2, 7 ], series := "L" 
> )
> gap> 
> 
> I don't know for sure if this is a typo or the function was renamed in GAP, 
> but it could be the former - I can see IsomorphismTypeInfoFiniteSimpleGroup 
> mentions dated back to 2003. It seems that the document you mention is dated 
> 2002 and refers to GAP 4.2, so it is plausible that some examples are not 
> reproducible and should be adapted to GAP 4.7. Most of such cases are covered in 
> the Chapter "Replaced and Removed Command Names" of the GAP Reference 
> manual (http://www.gap-system.org/Manuals/doc/ref/chap77.html), and in doubt 
> please just ask.
> 
> Best wishes
> Alexander
> 
> P.S. It should be possible to produce GAP teaching materials in various 
> languages using GAPDoc package, and run automated tests of their examples to 
> check that they all still work with new versions of GAP. This will simplify 
> their maintenance and their upgrading after major GAP releases.
> 
> 
> On 15 Sep 2014, at 05:06, buynnnmmm1 at yahoo.co.jp wrote:
> 
>> 
>> 
>>  Hello.
>>  It is an error to try to do in the Gap4.7.5 
> IsomorphismTypeFiniteSimpleGroup of P.27 of 
> http://sci.kj.yamagata-u.ac.jp/~waki/jpn/gap_docs/take_gap.pdf. 
>> 
>>  gap> s8:=Group((1,2),(1,2,3,4,5,6,7,8));
>>  Group([ (1,2), (1,2,3,4,5,6,7,8) ])
>>  gap> a8:=CommutatorSubgroup(s8,s8);
>>  Group([ (1,3,2), (2,4,3), (2,3)(4,5), (2,4,6,5,3), (2,5,3)(4,7,6), 
> (2,3)(5,6,8,7) ])
>>  gap> elab:= Group( (1,2)(3,4)(5,6)(7,8), (1,3)(2,4)(5,7)(6,8),  
> (1,5)(2,6)(3,7)(4,8));
>>  Group([ (1,2)(3,4)(5,6)(7,8), (1,3)(2,4)(5,7)(6,8), (1,5)(2,6)(3,7)(4,8) ])
>>  gap> norm:= Normalizer( a8, elab );;
>>  gap> hom:=NaturalHomomorphismByNormalSubgroup( norm , elab );
>>  <action epimorphism>
>>  gap> f := Image( hom );
>>  Group([ (), (), (), (4,5)(6,7), (4,6)(5,7), (2,3)(6,7), (2,4)(3,5), 
> (1,2)(5,6) ])
>>  gap> IsomorphismTypeFiniteSimpleGroup( f );
>>  Error, Variable: 'IsomorphismTypeFiniteSimpleGroup' must have a 
> value
>>  not in any function at line 16 of *stdin*
>> 
>> 
>>  However, I should be able to get the following output: In P.27 of this PDF 
> file.
>> 
>>  gap> IsomorphismTypeFiniteSimpleGroup( f );
>>  rec( series := "L", parameter := [ 2, 7 ],
>>  name := "A(1,7) = L(2,7) ~ B(1,7) = O(3,7) ~ C(1,7) = S(2,7) ~
>>  2A(1,7) = U(2\
>>  ,7) ~ A(2,2) = L(3,2)" )
>> 
>> 
>>  Could you tell me how to solve this problem? 
>>  How to use or probably been changed in accordance with the version up? 
>>  Or bug or probably are mixedin Gap version up?
>> 
>> 
>>                                    buynnnmmm1
>> 
>>  _______________________________________________
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>>  http://mail.gap-system.org/mailman/listinfo/forum
> 



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