Add an interface to Jean-Eric Pin's Semigroupe package

[nthiery]

Add an interface to Jean-Eric Pin's Semigroupe package

http://www.liafa.jussieu.fr/~jep/semigroupes.html

An experimental spkg is now on trac; here is the patch taken from the old Sage-Combinat patch server:

:attachment:trac_8360_semigroupe-interface-nt.patch

Status: advanced proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.

The following should hopefully get you started:

   sage -f https://github.com/sagemath/sage-prod/files/10648262/semigroupe-2.0-2.spkg.gz
   sage -combinat update
   sage -br

   sage: semigroupe?
   sage: semigroupe.tutorial?

Beware 'sage -f an_url' does not redownload the package if sage
already has a copy of it. So you may have to first do:

        rm <SAGE_ROOT>/spkg/optional/semigroupe-2.0.spkg

Update 2016-12-05: James Mitchel is reimplementing Semigroupe in C++, which will lift the main limitation (a single semigroup at a time):
https://james-d-mitchell.github.io/semigroupsplusplus/

This could be the occasion to revive this old code.

CC: @sagetrac-sage-combinat Jean-Eric.Pin@liafa.jussieu.fr @sagetrac-abmasse @tscrim

Component: algebra

Keywords: Semigroupes

Author: Florent Hivert, Jean-Eric Pin, Nicolas M. Thiéry

Issue created by migration from https://trac.sagemath.org/ticket/8360

[nthiery]

comment:1

Attachment: Semigroupe-2.0.spkg.gz

[nthiery]

Description changed:

--- 
+++ 
@@ -2,4 +2,8 @@
 
 http://www.liafa.jussieu.fr/~jep/semigroupes.html
 
-Patch and spkg under development on the Sage-Combinat server.
+Patch and spkg under development on the Sage-Combinat server:
+
+http://combinat.sagemath.org/hgwebdir.cgi/patches/file/tip/trac_8360_semigroupe-interface-nt.patch
+
+Status: more than a proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.

[nthiery]

Superceedes the previous spkg

[nthiery]

comment:2

Attachment: semigroupe-2.0.spkg.gz

[nthiery]

Description changed:

--- 
+++ 
@@ -2,8 +2,21 @@
 
 http://www.liafa.jussieu.fr/~jep/semigroupes.html
 
-Patch and spkg under development on the Sage-Combinat server:
+An experimental spkg is now on trac, and the patch is up and unguarded
+on the Sage-Combinat patch server:
 
 http://combinat.sagemath.org/hgwebdir.cgi/patches/file/tip/trac_8360_semigroupe-interface-nt.patch
 
-Status: more than a proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.
+So the following should hopefully get you started:
+
+   sage -f https://github.com/sagemath/sage-prod/files/10648261/Semigroupe-2.0.spkg.gz
+   sage -combinat update
+   sage -br
+
+   sage: semigroupe?
+   sage: semigroupe.tutorial?
+
+Status: advanced proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.
+
+
+

[nthiery]

Description changed:

--- 
+++ 
@@ -9,12 +9,14 @@
 
 So the following should hopefully get you started:
 
+```
    sage -f https://github.com/sagemath/sage-prod/files/10648261/Semigroupe-2.0.spkg.gz
    sage -combinat update
    sage -br
 
    sage: semigroupe?
    sage: semigroupe.tutorial?
+```
 
 Status: advanced proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.
 

[nthiery]

Description changed:

--- 
+++ 
@@ -7,7 +7,9 @@
 
 http://combinat.sagemath.org/hgwebdir.cgi/patches/file/tip/trac_8360_semigroupe-interface-nt.patch
 
-So the following should hopefully get you started:
+Status: advanced proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.
+
+The following should hopefully get you started:
 
 ```
    sage -f https://github.com/sagemath/sage-prod/files/10648261/Semigroupe-2.0.spkg.gz
@@ -18,7 +20,14 @@
    sage: semigroupe.tutorial?
 ```
 
-Status: advanced proof of concept, with interactions in both directions (building a semigroup in Semigroupe from Sage data). Main show stopper: one can only manipulate one semigroup at a time.
+Beware 'sage -f an_url' does not redownload the package if sage
+already has a copy of it. So you may have to first do:
+
+```
+        rm <SAGE_ROOT>/spkg/optional/semigroupe-2.0.spkg
+```
 
 
 
+
+

[saliola]

comment:5

There seems to be a problem on a 64bit machine. After installing the spkg, the following commands will cause Sage to segfault:

sage: W = CoxeterGroup(["H",4])
sage: S = semigroupe.AutomaticSemigroup(W.semigroup_generators(), W.one(), category = FiniteCoxeterGroups())
sage: S.cardinality()
------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occured in Sage.
...

The problem seems to be with compiling Semigroupe on a 64bit machine. After installing the package, the following segfaults:

karkwa: cd $SAGE_ROOT/local/bin
karkwa: Semigroupe
karkwa: ./Semigroupe
Segmentation fault
karkwa: ./SelfContainedTest 
Toto
a | 2  3  1 
b | 2  1  3 
c | 1  2  1 

Segmentation fault
karkwa: ./SemigroupeModuleTest 

a | 2  1 
b | 1  1 

Segmentation fault 

I think that the two test suites (I think they are test suites...) should be run by the spkg-check script.

[anneschilling]

comment:6

On a 32-bit machine, I obtain the following error:

sage: S = semigroupe.AutomaticSemigroup(W.semigroup_generators(), W.one(), category = FiniteCoxeterGroups())
sage: S.cardinality()
python(24860) malloc: *** vm_allocate(size=262144) failed (error code=3)
python(24860) malloc: *** error: can't allocate region
python(24860) malloc: *** set a breakpoint in szone_error to debug
memory allocation failed
memory usage :

size : 2^ used/allocated
0 310/312
1 21/22
2 109/109
3 73/73
4 49/50
5 5/6
6 9/9
7 3/3
8 1/1
9 1/1
10 1/2
11 0/1
12 0/0
13 0/1
14 1/1
15 25959/25959
16 0/0
17 0/0
18 0/0
19 0/0
20 0/0
21 0/0
22 0/0
23 0/0
24 0/0
25 0/0
26 0/0
27 0/0
28 0/0
29 0/0
30 0/0
31 0/0

total : 850645964/850657280 4-byte units used/allocated
.../Applications/sage-4.4/devel/sage-combinat/sage/combinat/crystals$

Anne