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Maple is the uncontested leader for computing symbolic
solutions to differential equations. Numerous improvements in Maple 15
further expand the classes of problems that can be handled.
Kamke Benchmark
Ordinary Differential Equations
Partial Differential Equations
PDE Tools

Kamke Benchmark
Maple 15 now computes symbolic solutions to 97% of the 1390 linear and nonlinear ODEs from the famous text, Differentialgleichungen by Kamke. Mathematica® 8 only handles 79%. Maple also solves these ODEs almost 10 times faster than Mathematica.

Looking at the details, Maple is the only system to solve any of the systems in some classes of ODEs:

| Kamke (1390 ODEs) |
Mathematica 8 |
Maple 15 |
| 1st order ODEs (576) |
86% (solved in 234 minutes) |
99% (solved in 26 minutes) |
| 2nd order linear ODEs (448) |
91% (39min) |
99.5% (2.3min) |
| 2nd order nonlinear ODEs (188) |
70% (78min) |
97% (14min) |
| 2nd order reducible nonlinear ODEs (58) |
0% (23min) |
86% (3min) |
| 3rd order linear ODEs (85) |
67.5% (23min) |
91% (2.5min) |
| 4th order linear ODEs (45) |
77% (5.8min) |
93% (0.5min) |
| 5th order linear ODEs (12) |
67% (7.4min) |
92% (0.5min) |
| High-order nonlinear ODEs (12) |
67% (1.5min) |
100% (0.6min) |
| High-order reducible nonlinear ODEs (5) |
0% (0.5min) |
100% (0.2min) |
| Total |
79% (408min) |
96% (49min) |

Ordinary Differential Equations (ODEs)
By using new algorithms, the dsolve command can now solve two
additional 1st order and eleven 2nd order nonlinear ODE families, all of
them parametrized by arbitrary functions of the independent and
dependent variables and out of reach of the previously existing solving
methods.



Partial Differential Equations (PDEs)
A significant number of improvements and additions were made to the
PDEtools package, setting a new benchmark for the state-of-the-art in
symbolic computation and partial differential equation solving and
symmetry analysis.
New commands: FunctionFieldSolutions, SymmetryCommutator and SymmetryGauge
Three new commands were added to PDEtools.
- FunctionFieldSolutions is a new command that
involves an innovative approach to computing exact solutions to DE
systems involving mathematical functions, possibly inequations, ODEs and
also non-differential equations. In these cases, due to the presence of
nonpolynomial objects, the original Maple approach was to decouple the
system using differential polynomial extensions. This approach,
although powerful, sometimes failed to solve the problem. The new
approach in FunctionFieldSolutions skips that step
entirely and instead searches for solutions that can be written as a
power series (with some upper bound degree n) in the mathematical functions and its derivatives (up to some upper bound differential order m), having for coefficients multivariable polynomials (with some upper bound degree r).
In turn these polynomials have undetermined coefficients that get
adjusted, resulting in the solution. To compute the key values of n, m, r
to construct these function field solutions, the new command maps the
problem into one that can be tackled with the existing
PDEtools:-Library:-UpperBounds (see PDEtools[Library]).
- SymmetryCommutator is a new command to compute
the commutator between two symmetries, given either as lists of
infinitesimals or as infinitesimal generator procedures. This command is
useful when studying the properties of a group of symmetries or when
deriving the group constants or relations to make the group complete.
- SymmetryGauge is a new command to gauge PDE
symmetries. It is well known that an ODE symmetry can be rewritten in
different ways (see Xgauge). It is not so well known, but the same
happens with PDE symmetries. The ability to rewrite a symmetry is
relevant for a number of purposes. First, that permits identifying that
two apparently different symmetries are actually the same by rewriting
them in evolutionary form (gauge ξ = 0). Second, symmetries that appear
as dynamical ones can frequently be rewritten as pointlike, transforming
the usability of the symmetry from perhaps very difficult into
straightforward. Finally, depending on the form of the symmetry, by
rewriting them it is frequently possible to simplify its form
considerably so that invariants of canonical coordinates become
computable and so the symmetry can be used to reduce the number of
independent variables of PDE systems.





New functionality in the PDEtools package
- The following commands were significantly enhanced in their
functionality: ConservedCurrents, D_Dx, DeterminingPDE, Eta_k,
InfinitesimalGenerator, Infinitesimals, IntegratingFactors,
InvariantEquation and Solve.
- In Maple 15, the entire set of symmetry commands of PDEtools:
- Automatically use textbook mathematical jet notation on input and output;
- Handle list of infinitesimals or the corresponding symmetry generator operators in equal footing;
- Understand different jet notations as representing the same mathematical objects;
- Return list of infinitesimals with infinitesimal labels in
mathematical notation, unless your input contains infinitesimals without
labels;
- Return results in the jet notation of the input you pass to them;
- Optionally return in any jet notation you request.

Examples
Note the (new) presence of infinitesimal labels in this output. The
motivation behind all these changes is to have a computational
experience with symmetry analysis using true mathematical notation, as
close as possible as the one you use when computing with paper and
pencil.
Apart from the ability to compute conserved currents and integrating
factors of general types, ConservedCurrents and IntegratingFactors can
now specifically compute conserved currents and integrating factors of polynomial or functionfield types.



Eta_k: the returned table procedure eta that provides any desired
prolongation of the infinitesimals can now be indexed using independent
and dependent variables in jet notation, or their respective numeric
positions in the lists of independent and dependent variables (that is
jetnumbers notation). Correspondingly, the output will be in
jetvariables or jetnumbers notation. This implements a more natural
mathematical representation of infinitesimal prolongations while
providing an easy way to switch between notations, interactively or
within a program,

Infinitesimals understands more types of symmetries: evolutionary and
general, apart from pointlike and contact, and can compute
infinitesimals combining these types, as for instance in
And(evolutionary, polynomial), that is, dynamical symmetries with the _xi infinitesimals equal to zero and the _eta infinitesimals polynomial in the jet variables including all partial derivatives

InvariantEquation accepts a new optional argument, explicit, to indicate
that the invariant equation to be returned should have the form of an
explicit PDE system with all the highest derivatives isolated in the
left-hand sides. In addition, this command can now compute the PDE
system invariant under a set of generic dynamical symmetries, that is, symmetries where the corresponding infinitesimals depend directly on the derivatives of the unknowns of the problem.



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