Opened 3 years ago
Closed 2 years ago
#28982 closed enhancement (fixed)
Use CombinatorialPolyhedron to obtain faces lattice of polyhedra
Reported by:  ghkliem  Owned by:  

Priority:  major  Milestone:  sage9.2 
Component:  geometry  Keywords:  polyhedron, face lattice 
Cc:  jipilab, ghLaisRast  Merged in:  
Authors:  Jonathan Kliem  Reviewers:  JeanPhilippe Labbé, Matthias Koeppe 
Report Upstream:  N/A  Work issues:  
Branch:  6b7b5b6 (Commits, GitHub, GitLab)  Commit:  6b7b5b6c17a645f55766666295a0424de8efde72 
Dependencies:  #29583  Stopgaps: 
Description (last modified by )
We use CombinatorialPolyhedron
to compute the face lattice of a polyhedron.
Along the way we implement hasse_diagram
for CombinatorialPolyhedron
and Polyhedron_base
.
Instead of caching face_lattice
, we cache hasse_diagram
now.
This is much slower, but removes a memory leak. As hasse_diagram
is hardly used with #28646, this seems to be reasonable.
Caching the face lattice does create a memory leak:
sage: import gc sage: P = polytopes.cube() sage: P.my_face_lattice = P.face_lattice() sage: n = get_memory_usage() sage: P = polytopes.cube() sage: P.my_face_lattice = P.face_lattice() sage: _ = gc.collect() sage: n == get_memory_usage() False
Change History (36)
comment:1 Changed 3 years ago by
Branch:  → public/28982 

comment:2 Changed 3 years ago by
Commit:  → cfb153d6c9f2c110a2468a920a14f4fa3914735a 

comment:3 Changed 3 years ago by
Status:  new → needs_review 

comment:4 Changed 3 years ago by
Commit:  cfb153d6c9f2c110a2468a920a14f4fa3914735a → 41254c28fc83112e7b3b001a1b12c2995613ca8f 

Branch pushed to git repo; I updated commit sha1. New commits:
41254c2  fixed pyflakes warnings

comment:5 Changed 3 years ago by
Branch:  public/28982 → public/28982reb 

Commit:  41254c28fc83112e7b3b001a1b12c2995613ca8f → f249c9db8be362dbd8aa7adac95b672eddd6d3b4 
I changed to face lattice not to be set up with linear extension anymore.
New commits:
261feff  add hasse_diagram to combinatorial polyhedron

721cff6  implemented method hasse diagram for polyhedra

0768b90  use combinatorial polyhedron to obtain face lattice of polyhedron

c82545f  fixed pyflakes warnings

f249c9d  fixed failing doctest; face lattice can compute whether it is eulerian again

comment:6 Changed 3 years ago by
Few comments:
 Test that face lattice give no memory leak:: + Test that computing the face lattice does not lead to a memory leak::
 Return the hasse diagram of ``self``. + Return the hasse diagram of the face lattice of ``self``.
I will go more in depth soon.
Does this mean that we can remove the file hasse_diagram.py
?
comment:7 Changed 3 years ago by
Branch:  public/28982reb → public/28982reb2 

Commit:  f249c9db8be362dbd8aa7adac95b672eddd6d3b4 → f44afa26835ca7a4991864766c1f1c01c9e6f399 
New commits:
ef69d37  add hasse_diagram to combinatorial polyhedron

919af02  implemented method hasse diagram for polyhedra

f040df6  use combinatorial polyhedron to obtain face lattice of polyhedron

f9f7a42  fixed pyflakes warnings

f306cd0  fixed failing doctest; face lattice can compute whether it is eulerian again

f44afa2  improved documentation

comment:8 Changed 3 years ago by
Description:  modified (diff) 

comment:9 Changed 3 years ago by
Commit:  f44afa26835ca7a4991864766c1f1c01c9e6f399 → e9b3201a8b6dd36d5edf0ac54e4d554d9aaff6b4 

Branch pushed to git repo; I updated commit sha1. New commits:
e9b3201  improved doctest, gc.collect should be run before the test as well

comment:10 Changed 3 years ago by
Milestone:  sage9.1 → sage9.2 

Batch modifying tickets that will likely not be ready for 9.1, based on a review of the ticket title, branch/review status, and last modification date.
comment:11 Changed 3 years ago by
Reviewers:  → JeanPhilippe Labbé 

Status:  needs_review → needs_work 
Suggestions:
+ .. NOTE::  The face lattice is not cached, as long as this would create a memory leak. + The face lattice is not cached, as long as this creates a memory leak, see :trac:`28982`.
Hasse is a lastname, so you can capitalize it within the documentation.
Could the function below have more information? Like which order is meant to be simulated here? Inclusion or lex on indices of vertices, etc? Just one more sentence to specify might be nice?
+ def __lt__(self, other):
+ r"""
+ Compare faces of the same polyhedron.
+
+ EXAMPLES::
+
+ sage: P = polytopes.simplex()
+ sage: C = CombinatorialPolyhedron(P)
+ sage: F1 = C.face_by_face_lattice_index(0)
+ sage: F2 = C.face_by_face_lattice_index(1)
+ sage: F1 < F2
+ True
+ """
+ return hash(self) < hash(other)
Is there a reason why the hasse diagram of the combinatorial polyhedron is not cached?
comment:12 Changed 3 years ago by
Branch:  public/28982reb2 → public/28982reb3 

Commit:  e9b3201a8b6dd36d5edf0ac54e4d554d9aaff6b4 → 92842be2496dd8fd327f84f79a3dd3b3cf1dbfca 
Status:  needs_work → needs_review 
comment:13 Changed 3 years ago by
Status:  needs_review → needs_work 

Great! Thanks for the quick changes. You forgot a capital "H" in the last commit. Apart from that it is good to go!
once you make this last typo change, you can set it to positive review on my behalf.
comment:14 Changed 3 years ago by
Commit:  92842be2496dd8fd327f84f79a3dd3b3cf1dbfca → 708dd7dcf0dbc70c9c53a3c4946624a389b2580e 

Branch pushed to git repo; I updated commit sha1. New commits:
708dd7d  typo

comment:17 Changed 3 years ago by
Branch:  public/28982reb3 → public/28982reb4 

Commit:  708dd7dcf0dbc70c9c53a3c4946624a389b2580e → 819d5433d00510a69bc43b8138296713cd9853f5 
Status:  needs_work → needs_review 
Last 10 new commits:
d7bc78d  use combinatorial polyhedron to obtain face lattice of polyhedron

d6f874e  fixed pyflakes warnings

7e53757  fixed failing doctest; face lattice can compute whether it is eulerian again

015232c  improved documentation

651e621  improved doctest, gc.collect should be run before the test as well

898feee  cache hasse_diagram of combinatorial polyhedron

ff18524  improved documentation

6497d62  explain __lt__

4e19d6c  typo

819d543  fix failing doctest

comment:18 Changed 3 years ago by
Status:  needs_review → needs_work 

It doesn't seem to build... See patchbot.
comment:19 Changed 3 years ago by
Branch:  public/28982reb4 → public/28982reb5 

Commit:  819d5433d00510a69bc43b8138296713cd9853f5 → 0e865a04996fe35097ffd04fbdb879b97732e2ce 
Status:  needs_work → needs_review 
Last 10 new commits:
5edeaa3  fixed pyflakes warnings

00f234c  fixed failing doctest; face lattice can compute whether it is eulerian again

ab0a789  improved documentation

fefe3b2  improved doctest, gc.collect should be run before the test as well

4bc4957  cache hasse_diagram of combinatorial polyhedron

381f7d9  improved documentation

404efca  explain __lt__

84746b1  typo

587738d  fix failing doctest

0e865a0  missing import

comment:21 Changed 3 years ago by
Status:  positive_review → needs_work 

sage t long warnlong 36.4 src/sage/geometry/polyhedron/face.py ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 454, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation Failed example: face = p.face_lattice()[5] Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation[1]>", line 1, in <module> face = p.face_lattice()[Integer(5)] File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/geometry/polyhedron/base.py", line 5873, in face_lattice return FiniteLatticePoset(self.hasse_diagram()) File "sage/misc/cachefunc.pyx", line 2310, in sage.misc.cachefunc.CachedMethodCallerNoArgs.__call__ (build/cythonized/sage/misc/cachefunc.c:12712) self.cache = f(self._instance) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/geometry/polyhedron/base.py", line 5901, in hasse_diagram return D.relabel(index_to_polyhedron_face, inplace=False, immutable=True) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/graphs/generic_graph.py", line 21864, in relabel complete_partial_function = complete_partial_function) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/graphs/generic_graph.py", line 21929, in relabel raise NotImplementedError("Non injective relabeling") NotImplementedError: Non injective relabeling ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 455, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation Failed example: face Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation[2]>", line 1, in <module> face NameError: name 'face' is not defined ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 457, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation Failed example: face.ambient_Hrepresentation() Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation[3]>", line 1, in <module> face.ambient_Hrepresentation() NameError: name 'face' is not defined ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 462, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation Failed example: face.n_ambient_Hrepresentation() Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation[4]>", line 1, in <module> face.n_ambient_Hrepresentation() NameError: name 'face' is not defined ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 481, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation Failed example: face = p.face_lattice()[5] Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation[1]>", line 1, in <module> face = p.face_lattice()[Integer(5)] File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/geometry/polyhedron/base.py", line 5873, in face_lattice return FiniteLatticePoset(self.hasse_diagram()) File "sage/misc/cachefunc.pyx", line 2310, in sage.misc.cachefunc.CachedMethodCallerNoArgs.__call__ (build/cythonized/sage/misc/cachefunc.c:12712) self.cache = f(self._instance) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/geometry/polyhedron/base.py", line 5901, in hasse_diagram return D.relabel(index_to_polyhedron_face, inplace=False, immutable=True) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/graphs/generic_graph.py", line 21864, in relabel complete_partial_function = complete_partial_function) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/graphs/generic_graph.py", line 21929, in relabel raise NotImplementedError("Non injective relabeling") NotImplementedError: Non injective relabeling ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 482, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation Failed example: face Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation[2]>", line 1, in <module> face NameError: name 'face' is not defined ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 484, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation Failed example: face.ambient_Vrepresentation() Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation[3]>", line 1, in <module> face.ambient_Vrepresentation() NameError: name 'face' is not defined ********************************************************************** File "src/sage/geometry/polyhedron/face.py", line 486, in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation Failed example: face.n_ambient_Vrepresentation() Exception raised: Traceback (most recent call last): File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 680, in _run self.compile_and_execute(example, compiler, test.globs) File "/home/release/Sage/local/lib/python3.7/sitepackages/sage/doctest/forker.py", line 1104, in compile_and_execute exec(compiled, globs) File "<doctest sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation[4]>", line 1, in <module> face.n_ambient_Vrepresentation() NameError: name 'face' is not defined ********************************************************************** 2 items had failures: 4 of 6 in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Hrepresentation 4 of 6 in sage.geometry.polyhedron.face.PolyhedronFace.n_ambient_Vrepresentation [119 tests, 8 failures, 0.44 s]
comment:22 Changed 3 years ago by
Dependencies:  → #29583, #28894 

comment:23 Changed 3 years ago by
Dependencies:  #29583, #28894 → #29583 

comment:24 Changed 3 years ago by
Branch:  public/28982reb5 → public/28982reb6 

Commit:  0e865a04996fe35097ffd04fbdb879b97732e2ce → f4e1deccef14f7aa3dcf1e19241ac042157e4f92 
I rebased on top of #29583 (as there is some merge conflict).
I also fixed the error in #28894, which caused the doctest failure. Now this ticket works by itself and on top of #28894. At least the following tests pass on my machine with and without #28894:
sage t long p 8 src/doc/en/thematic_tutorials/geometry sage t long p 8 src/sage/geometry/polyhedron/ sage t long p 8 src/sage/plot/
Last 10 new commits:
cb5e58a  fixed pyflakes warnings

76a7247  fixed failing doctest; face lattice can compute whether it is eulerian again

f0c9f6f  improved documentation

b76f653  improved doctest, gc.collect should be run before the test as well

a405173  cache hasse_diagram of combinatorial polyhedron

d2c5332  improved documentation

e59938a  explain __lt__

8fbc9c2  typo

0fbd87d  fix failing doctest

f4e1dec  missing import

comment:25 Changed 3 years ago by
Status:  needs_work → needs_review 

comment:27 Changed 2 years ago by
Branch:  public/28982reb6 → public/28982reb7 

Commit:  f4e1deccef14f7aa3dcf1e19241ac042157e4f92 → 22974744b2b580cf94737ca9d04734d89687b73e 
Status:  needs_work → needs_review 
comment:28 Changed 2 years ago by
+ if polyhedron.dimension() == 0: + # In case of the 0dimensional polyhedron, + # there is a facets but no inequality. + H_indices = tuple(range(n_equations)) +
The comment needs rewording
comment:29 Changed 2 years ago by
Status:  needs_review → needs_work 

comment:30 Changed 2 years ago by
Branch:  public/28982reb7 → public/28982reb8 

Commit:  22974744b2b580cf94737ca9d04734d89687b73e → 92487de288ea07cc6f39df2befb5383935285537 
Status:  needs_work → needs_review 
comment:31 followup: 33 Changed 2 years ago by
Reviewers:  JeanPhilippe Labbé → JeanPhilippe Labbé, Matthias Koeppe 

+ def __lt__(self, other): + r""" + Compare faces of the same polyhedron. + + This is a helper function. + In order to construct a Hasse diagram (a digraph) with combinatorial faces, + we must define some order relation that is compatible with the Hasse diagram. + + Any order relation compatible with ordering by dimension is suitable. + We us :meth:`__hash__` to define the relation.
I don't fully understand what's happening in that hash function. If one uses the face iterator in nondual mode, is the resulting order relation still correct?
comment:32 Changed 2 years ago by
Commit:  92487de288ea07cc6f39df2befb5383935285537 → 6b7b5b6c17a645f55766666295a0424de8efde72 

Branch pushed to git repo; I updated commit sha1. New commits:
6b7b5b6  make hash function consistent with dual mode

comment:33 Changed 2 years ago by
Replying to mkoeppe:
+ def __lt__(self, other): + r""" + Compare faces of the same polyhedron. + + This is a helper function. + In order to construct a Hasse diagram (a digraph) with combinatorial faces, + we must define some order relation that is compatible with the Hasse diagram. + + Any order relation compatible with ordering by dimension is suitable. + We us :meth:`__hash__` to define the relation.I don't fully understand what's happening in that hash function. If one uses the face iterator in nondual mode, is the resulting order relation still correct?
You are right.
I'm surprised it worked that way.
The hash function should be consistent now. And __lt__
returns None
if the faces are clearly incompatible.
What's nice about this hash function, if I understand it correctly, is that it allows to store faces in sets etc.
comment:34 Changed 2 years ago by
Status:  needs_review → positive_review 

comment:36 Changed 2 years ago by
Branch:  public/28982reb8 → 6b7b5b6c17a645f55766666295a0424de8efde72 

Resolution:  → fixed 
Status:  positive_review → closed 
Branch pushed to git repo; I updated commit sha1. New commits:
add hasse_diagram to combinatorial polyhedron
implemented method hasse diagram for polyhedra
use combinatorial polyhedron to obtain face lattice of polyhedron