Opened 11 years ago
Last modified 7 years ago
#9625 new defect
solve hangs on a small algebraic system with 4 equations in 4 unknowns
Reported by: | zimmerma | Owned by: | burcin |
---|---|---|---|
Priority: | major | Milestone: | sage-6.4 |
Component: | calculus | Keywords: | |
Cc: | jason, kcrisman, malb, was | Merged in: | |
Authors: | Reviewers: | ||
Report Upstream: | N/A | Work issues: | |
Branch: | Commit: | ||
Dependencies: | Stopgaps: |
Description
The following command hangs with Sage 4.4.4:
var = [s,t,w,z] sys = [-83065036657810695629*s^2 + 83065036657810695629*t*w - 68998003149632685\ 30106646060491053792528*s - 395748941050538664245556665401237631434*w + 6899800\ 710712292645598903080085537498136631434, 124597554986716043444*s^2 - 1245975549\ 86716043444*t*w + 10349700472444902795201501609065485036608*s - 268851627794621\ 336185309600880111037777*w - 10349700203593399598010554584812612113052962223, -\ 282961047374832134660970*s^2 - 8410334961603332923585*s*z + 8410334961603332923\ 585*t^2 + 282961047374832134660970*t*w - 23504169772922374247873205131210852239\ 883040*s - 30616067929472784598571512251700309424241225*t - 7028115267891297114\ 2272480500812537457*w - 349302390945015468969034253953644989640360*z - 94573827\ 6702217921211141587964108207667243789392, -5322973679105824997312280*s^2 + 9157\ 920291523629102472*s*z - 9157920291523629102472*t^2 + 5322973679105824997312280\ *t*w - 442153003783476173947515315017330812575960960*s + 3127353268883216472554\ 94866020283168151616125*t - 167582752514587776396443776337970730676*w + 3803514\ 92362350173958234007398030593401152*z - 176904945185291980573382635775655917064\ 32113716525] solve(sys,var)
In comparison, Maple 13 answers in 38 milliseconds...
Change History (14)
comment:1 follow-ups: ↓ 2 ↓ 3 Changed 11 years ago by
- Milestone changed from sage-4.5.2 to 4.5.3
comment:2 in reply to: ↑ 1 Changed 11 years ago by
Replying to mpatel:
But I think it's too late in the 4.5.2 release cycle to fix this problem, so I've changed the milestone to 4.5.3.
Or is there a simple fix someone can post very soon?
comment:3 in reply to: ↑ 1 Changed 11 years ago by
Replying to mpatel:
Possibly naive question: Is this a problem in the Maxima wrapper or in Maxima itself?
it seems to be a problem in the main Maxima to_poly_solve
function. With the option
use_grobner=true
it returns (but never gets a chance to get there in the try ... except).
Out of curiosity: Does this system have a special provenance?
yes, it comes from Coppersmith's algorithm to find small roots of a polynomial system, which was itself used by a master student (Thomas Prest) in the context of polynomial selection for the Number Field Sieve with two non-linear polynomials.
Paul
comment:4 follow-up: ↓ 6 Changed 11 years ago by
- Cc jason kcrisman was added
Is this purely an upstream problem?
comment:5 Changed 11 years ago by
- Milestone changed from sage-4.5.3 to sage-4.6
The 4.5.3 series will soon be in "feature freeze."
comment:6 in reply to: ↑ 4 Changed 11 years ago by
Replying to mpatel:
Is this purely an upstream problem?
I have no idea. The maxima SPKG.txt contains no maintainer name, thus I don't know who to put in cc to report this problem upstream (if needed). Can anybody help?
Paul
comment:7 Changed 11 years ago by
Eventually someone will look into it - it can just take a while to have the time. I'll try to look at this soon.
comment:8 Changed 11 years ago by
- Priority changed from blocker to major
comment:9 follow-up: ↓ 10 Changed 11 years ago by
I'm not sure if this is related or not:
z = var('z') f = 1 - z - z^2 - z^3 - z^4 - z^5 solve(f == 0,z)
this takes about 2 minutes before
Exception RuntimeError: 'maximum recursion depth exceeded while calling a Python object' in <type 'exceptions.TypeError'> ignored Exception RuntimeError: 'maximum recursion depth exceeded while calling a Python object' in <type 'exceptions.TypeError'> ignored Exception RuntimeError: 'maximum recursion depth exceeded in __subclasscheck__' in <type 'exceptions.TypeError'> ignored Exception RuntimeError: 'maximum recursion depth exceeded in __subclasscheck__' in <type 'exceptions.TypeError'> ignored Exception RuntimeError: 'maximum recursion depth exceeded while calling a Python object' in <type 'exceptions.GeneratorExit'> ignored Exception RuntimeError: 'maximum recursion depth exceeded while calling a Python object' in <type 'exceptions.GeneratorExit'> ignored Exception GeneratorExit in <generator object <genexpr> at 0x6af3a00> ignored Traceback (most recent call last): File "<stdin>", line 1, in <module> File "_sage_input_100.py", line 10, in <module> exec compile(u'open("___code___.py","w").write("# -*- coding: utf-8 -*-\\n" + _support_.preparse_worksheet_cell(base64.b64decode("c29sdmUoZiA9PSAwLHop"),globals())+"\\n"); execfile(os.path.abspath("___code___.py"))' + '\n', '', 'single') File "", line 1, in <module> File "/tmp/tmpTusLV8/___code___.py", line 3, in <module> exec compile(u'solve(f == _sage_const_0 ,z)' + '\n', '', 'single') File "", line 1, in <module> File "/tmp/tmpfp2kNu/___code___.py", line 7, in solve z = solve(z,n-_sage_const_1 ) ... 2000 or so lines ... File "/tmp/tmpfp2kNu/___code___.py", line 7, in solve z = solve(z,n-_sage_const_1 ) File "/tmp/tmpfp2kNu/___code___.py", line 4, in solve if n <= _sage_const_0 : File "expression.pyx", line 1647, in sage.symbolic.expression.Expression.__nonzero__ (sage/symbolic/expression.cpp:8049) File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/relation.py", line 381, in test_relation_maxima m = relation._maxima_() File "expression.pyx", line 433, in sage.symbolic.expression.Expression._maxima_ (sage/symbolic/expression.cpp:3382) File "sage_object.pyx", line 379, in sage.structure.sage_object.SageObject._interface_ (sage/structure/sage_object.c:3374) File "sage_object.pyx", line 468, in sage.structure.sage_object.SageObject._maxima_init_ (sage/structure/sage_object.c:5083) File "expression.pyx", line 458, in sage.symbolic.expression.Expression._interface_init_ (sage/symbolic/expression.cpp:3510) File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 216, in __call__ return self.relation(ex, operator) File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 459, in relation return "%s %s %s"%(self(ex.lhs()), self.relation_symbols[operator], File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 214, in __call__ return self.arithmetic(ex, operator) File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 505, in arithmetic args = ["(%s)"%self(op) for op in ex.operands()] File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 201, in __call__ return self.pyobject(ex, obj) File "/home/boothby/sage-4.4.4/local/lib/python2.6/site-packages/sage/symbolic/expression_conversions.py", line 443, in pyobject return getattr(obj, self.name_init)() File "sage_object.pyx", line 468, in sage.structure.sage_object.SageObject._maxima_init_ (sage/structure/sage_object.c:5083) File "integer.pyx", line 4329, in sage.rings.integer.Integer._interface_init_ (sage/rings/integer.c:24709) File "integer.pyx", line 815, in sage.rings.integer.Integer.__repr__ (sage/rings/integer.c:7526) RuntimeError: maximum recursion depth exceeded while calling a Python object
comment:10 in reply to: ↑ 9 Changed 11 years ago by
Dang, can't undo comments. This is entirely user error, and has nothing to do with this ticket.
comment:11 Changed 8 years ago by
- Milestone changed from sage-5.11 to sage-5.12
comment:12 Changed 8 years ago by
- Milestone changed from sage-6.1 to sage-6.2
comment:13 Changed 7 years ago by
- Milestone changed from sage-6.2 to sage-6.3
comment:14 Changed 7 years ago by
- Milestone changed from sage-6.3 to sage-6.4
I see this problem on both bsd and sage.math. Pressing Control-C yields
Possibly naive question: Is this a problem in the Maxima wrapper or in Maxima itself?
On sage.math, Maple 12 responds to
solve({...}, [s, t, w, z]);
almost immediately withBut I think it's too late in the 4.5.2 release cycle to fix this problem, so I've changed the milestone to 4.5.3.
Out of curiosity: Does this system have a special provenance?