Thanks Nasser. Is there an easy way to access this database of differential equations?
It would be useful for SymPy to test against things like this in CI somehow. Oscar On Thu, 13 Mar 2025 at 22:19, 'nma%12...@gtempaccount.com' via sympy <sympy@googlegroups.com> wrote: > > fyi: > > This post is also available in plain text here > > Sympy 1.13.3 dsolve was added to the current > Computer Algebra Independent Differential Equations tests. > > This version of the tests has about 20,000 differential equations. > > This is the final result showing percentage solved > -------------------------------------------------- > > Maple 2024.2 (windows 10) 96.219% > Mathematica 14.2 (windows 10) 95.592% > Sympy 1.13.3 (Linux) 70.477% > > In the above result, a problem which was solved by Sympy using > series when hint is not series, is considered as not solved. > > No verification is made if solution is correct or not for any CAS. > > 3 minutes timelimit was given to solving each ode, else it is considered > failed. > > The pdf and web pages contain full details and lookup tables > with the complete commands used for each problem in plain > text to make it easy to copy each command from either the pdf or > the web page and try it yourself. > > For sympy, there are also lookup tables showing all the > exceptions generated and links to each problem with with exception. This > is in section 5.7. > > There were 625 problems which generated an exception. > > These do not include standard exceptions such as "NotImplementedError" > or "Timed Out". > > The exceptions generated and selected to show in the table are: > --------------------------------------------------------------- > > TypeError : bad operand type for unary -: list > RecursionError : maximum recursion depth exceeded > TypeError : cannot determine truth value of Relational > TypeError : NoneType object is not subscriptable > ValueError : Expected Expr or iterable but got None > ZeroDivisionError : polynomial division > TypeError : property object is not iterable > TypeError : < not supported between instances of NoneType and Zero > IndexError : list index out of range > AssertionError : [False] > KeyError : _y > KeyError : F2_ > KeyError : ordered_hints > TypeError : < not supported between instances of NoneType and y > NonlinearError : nonlinear term: sqrt(-a*b) > TypeError : argument of type Mul is not iterable > ValueError : Rational Solution doesnt exist > TypeError : argument of type NegativeOne is not iterable > IndexError : tuple index out of range > PolynomialDivisionFailed > TypeError : invalid input: 1 - (-21 + 4*sqrt(5))/(-1 + 2*sqrt(5)) > TypeError : Invalid NaN comparison > TypeError : Symbol object cannot be interpreted as an integer > TypeError : Mul object cannot be interpreted as an integer > TypeError : Add object cannot be interpreted as an integer > TypeError : invalid input (many of these) > NotInvertible : zero divisor > ODEMatchError : nth_linear_constant_coeff_undetermined_coefficients solver > cannot > KeyError : Derivative(y(t), (t, 2)) > KeyError : Derivative(y(t), t) > ValueError : substitution cannot create dummy dependencies > AttributeError : list object has no attribute func > TypeError : argument of type Pow is not iterable > HeuristicGCDFailed : no luck > TypeError : Invalid comparison of non-real 1 + sqrt(7)*I > TypeError : exp takes exactly 1 argument (2 given) > ValueError : function with different numbers of args > ValueError : dsolve() and classify_ode() only work with functions of one > variable, not t > PolynomialError : non-commutative expressions are not supported > ValueError : It solves only those systems of equations whose orders are equal > TypeError : < not supported between instances of NoneType and x > > The differential equations are all valid and been tested on Maple and > Mathematica. These were converted to Python from Maple, using Maple's > builtin package CodeGeneration > > There were few cases which the conversion did not produce valid result > that can be used in Sympy and these were all then corrected by hand. This > process > took 30 days to complete. > > Note: The PDF file is very large (over 33,000 pages). So it > can be little slow to open in the browser. > > Reports written in Latex and converted to PDF and HTML using > texlive (lualatex and tex4ht). > > I can no longer login to github as I can't figure how to get code for it, so > if anyone wants to use this to enter bug reports for sympy's dsolve, they are > welcome to. > > --Nasser > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sympy+unsubscr...@googlegroups.com. > To view this discussion visit > https://groups.google.com/d/msgid/sympy/45b0cc5b-75c0-4c20-b37b-3cdddd876372n%40googlegroups.com. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. 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