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Permutation for orders 3^7,5^7, 7^7, 11^7 are wrongly documented and implemented #38

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hulpke opened this issue Sep 6, 2018 · 5 comments · Fixed by #46
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Permutation for orders 3^7,5^7, 7^7, 11^7 are wrongly documented and implemented #38

hulpke opened this issue Sep 6, 2018 · 5 comments · Fixed by #46
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@hulpke
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hulpke commented Sep 6, 2018 •
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There was a renumbering of small groups of order 5^7, 7^7, 11^7. Bettina Eick sent me e.g. the following permutation for 5^7 that corrects the numbering to be compatible with Magma:

    perm5  := [1];
Append(perm5, [ 30083, 30084, 30085, 30086 ]);
Append(perm5, [2..30082]);

In small.gd this permutation exist in comments, but then in SMALL_GROUPS_PERM5 a different permutation is built up. Also the documentation and tests claim the permutation is an involution, which is not true.

This was put in wrongly in
b44d824

(Similar errors are in order 7^7 and 11^7)

As a result, the numbering used by GAP is different than in Magma, Viz (from Mark Lewis):

In Magma:  g := SmallGroup (5^7, 348);

yielded:  Exponent (g);
             125
             DerivedLength (g);
             2

In GAP:  g := SmallGroup (5^7,348);
           Exponent (g);
           25
           DerivedLength (g);
           3

This discrepancy needs to be documented and fixed. Given that users consider it as the GAP library this should be part of changes in a release.
@hulpke hulpke changed the title Permutation for degree 7(at least) is wrongly documented and implemented Permutation for orders 5^7, 7^7, 11^7 are wrongly documented and implemented Sep 6, 2018
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 11, 2018
@hulpke
FIX: Align ordering with Magma for degree 5^7
0a2c69a 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38
markuspf pushed a commit to markuspf/smallgrp that referenced this issue Sep 22, 2018
Fix permutations applied to groups of order 5^7,7^7,11^7
69304db 
Closes gap-packages#38
markuspf pushed a commit to markuspf/smallgrp that referenced this issue Sep 22, 2018
Fix permutations applied to groups of order 5^7,7^7,11^7
bdf2bab 
Closes gap-packages#38
@markuspf markuspf mentioned this issue Sep 22, 2018
Closed
50 tasks
@hulpke hulpke changed the title Permutation for orders 5^7, 7^7, 11^7 are wrongly documented and implemented Permutation for orders 3^7,5^7, 7^7, 11^7 are wrongly documented and implemented Oct 10, 2018
@hulpke
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hulpke commented Oct 10, 2018

I have now compared the groups for exponent p^7, 3<=p<=11 explicitly between GAP and MAGMA and there are sighnificant discrepancies beyond the assumed simple shift.
I will prepare a PR that provides permutations that I checked.

hulpke added a commit to hulpke/smallgrp that referenced this issue Oct 10, 2018
@hulpke
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
f4f445b 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38
@hulpke
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hulpke commented Oct 10, 2018

@markuspf Comparing with Magma, the changes turn out to be more than the easy shifts, I thus submitted a PR of my own.

@olexandr-konovalov olexandr-konovalov mentioned this issue Nov 9, 2018
Closed
31 tasks
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 12, 2019
@hulpke
# This is a combination of 2 commits.
fe387de 
# This is the 1st commit message:

FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7

The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

# This is the commit message gap-packages#2:

Removed the old tests

as they required that the permutations were of small support. (They also were
wrong)
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 12, 2019
@hulpke
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
ec4229c 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Version number change. Fixed hashmark and added tests

Added documentation for the new ordering.
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 12, 2019
@hulpke
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
a3b7052 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Version number change. Fixed hashmark and added tests

Added documentation for the new ordering.
@hulpke hulpke mentioned this issue Sep 12, 2019
Merged
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 12, 2019
@hulpke
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
6414985 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Version number change. Fixed hashmark and added tests

Added documentation for the new ordering.
fingolfin pushed a commit to hulpke/smallgrp that referenced this issue Sep 20, 2019
@hulpke @fingolfin
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
0cde2d9 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to deermine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Version number change. Fixed hashmark and added tests

Added documentation for the new ordering.
hulpke added a commit to hulpke/smallgrp that referenced this issue Sep 20, 2019
@hulpke
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
5f1d813 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to determine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Fixed hashmark and added tests

Added documentation for the new ordering.
fingolfin pushed a commit to hulpke/smallgrp that referenced this issue Sep 20, 2019
@hulpke @fingolfin
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
3a81017 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to determine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix gap-packages#38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Fixed hashmark and added tests

Added documentation for the new ordering.
fingolfin pushed a commit that referenced this issue Sep 20, 2019
@hulpke @fingolfin
FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7
17d6c1e 
The permutations applied had been wrongly implemented and were based on
wrong data. New permutations, based on explicitly comparing with Magma data
were used to determine correct permutations.

The test for the permutations in `ordering.tst` was changed, as the old test
relied on the permutations having small support, which is not true any
longer.

This will fix #38

Removed the old tests as they required that the permutations were of small
support. (They also were wrong)

Fixed hashmark and added tests

Added documentation for the new ordering.
@olexandr-konovalov
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@hulpke the fix should perhaps be mentioned in the release notes for GAP 4.11 under "packages"? If so, could you provide a description please?

@hulpke
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hulpke commented Sep 21, 2019

@alex-konovalov
Release notes:
The arrangement of small groups in degrees p^7, p=3,5,7,11, has been corrected.

Once anyone lets me know that a new version has been wrapped and is available for download I will write a mail to the forum, explaining details.

@olexandr-konovalov
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Thanks @hulpke. Shall we add "to ensure that their numbering is the same in GAP and Magma"?

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FIX: Align ordering with Magma for orders 3^7,5^7,7^7,11^7 hulpke/smallgrp
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