Jets home page

About Jets

Jets is a set of Maple procedures to facilitate solution of differential equations in total derivatives on diffieties. Otherwise said, Jets is a tool to compute symmetries, conservation laws, zero-curvature representations, recursion operators, any many other invariants of systems of partial differential equations.

Jets implements the algorithms described in M. Marvan, Sufficient set of integrability conditions of an orthonomic system. Foundations of Computational Mathematics 9 (2009) 651-674.

System requirements

Jets is developed and tested using the current Maple version (Maple 17 at this time) and can be used with Maple version 15 or higher on all platforms where Maple is available. Previous versions of Maple are no more supported.

License

Jets is a freeware, distributed under the GNU General Public License as published by the Free Software Foundation. In particular, it is distributed without any warranty, just in the hope that it will be useful.

Whenever results of your scientific work depend on use this software, you should consider making a reference to
H. Baran and M. Marvan, Jets. A software for differential calculus on jet spaces and diffieties
and/or to the paper
M. Marvan, Sufficient set of integrability conditions of an orthonomic system, Foundations of Computational Mathematics 9 (2009) 651-674.

Download

Jets consists of single file Jets.s.

Installation

No installation is needed. Put the file Jets.s to the Maple home directory (resp. anywhere else you have access to) and read it in by the Maple command
read(`Jets.s`);
resp.
read("The complete file path to Jets.s file");

For example, on Linux/Mac platform use
read("~/Desktop/Jets.s");
Note that on Windows, backslash in filepath must be in Maple written as `\\`, for example
read(`C:\\Program files\\Maple 9.5\\Jets.s`); After entering the read command you must see something like
JETS 5.6 Differential calculus on jet spaces and diffieties for Maple 10+ as of 20 Jan 2010
if you succeeded (the details may vary with Jets version). Please see documentation for details.

Hint: If you cannot read in the Jets.s file because it is found but not readable, make sure you have saved it as a plain text file and it has line endings corresponding to your operating system.

Installation troubleshooting

If you obtain an error message Error, unable to read `Jets.s` you probably have "path-problem": Maple is looking for Jets.s in another directory than you expected. Please specify the full and correct path to Jets.s file in read statement.
Respect your operating system file and directory names and separators conventions. Note that on Windows platform, the backslash(es) in filepath in Maple read statement must be written as `\\`.
For example
read(`C:\\Program files\\Maple 9.5\\Jets.s`);
See ?read and ?filenames in your Maple help for details.
If you cannot read in the Jets.s file because it is found but not readable, make sure you have saved it as a plain text file and it has line endings corresponding to your operating system.
The downloaded Jets.s file has Unix line endings (LF) by default. If your operating system uses different ones, you maybe have to convert it (this is the only problem with porting Jets to different operating systems).
There is a simple test worksheet available. Put it to the same directory as the main Jets.s file and execute, if you obtain any error message or the last output is something other than "OK", something is broken. If you save this worksheet and send it to us, maybe we can help.

Documentation

There is a common Jet guide pdf documentation file (together with some examples) for all the versions of Jets at this moment.

Tutorial

Basic course tutorial examples

Advanced course tutorial examples

Authors

The authors of Jets are Hynek Baran and Michal Marvan .
Please dont mind to contact us (Hynek[dot]Baran[at]math[dot]slu[dot]cz or Michal[dot]Marvan[at]math[dot]slu[dot]cz) if you have any trouble or you have successfully used Jets.

A Brief Version History

Version	Release date	New features	Tested against Maple version	Funding project
5.95 (current)	May 2022	Maple 2022 compatibility issues (reduce() renamed to pdreduce()), `divideout/unks`: a^e is divided out when a is nonzero, `Vars/<<`() call can be indexed by specific Varordering (e.g. `Vars/<<`['degree','reverse']), unkl(), unkL() gives a list of unks (and its sorted version, Varordering may be given by index)	Maple 2015, 2022
5.93	May 2019	testing new nonlinear resolve implementation in file (cat(jets_new_resolve_enable, "/Jets.newresolve.s")), LVar returns NULL on expressions without Vars, numerous bug fixes in the computation of coverings (MM 23.4.2019)	Maple 2015
5.91	Oct 2018	Vars has option cache, resolve FAILs collecting introduced, NewIntSeq() introduced, Report macro changed to inlined function, New resolve implementation (jets_new_resolve_enable) removed from the Jets.s source file to the Jets.newresolve.s file	Maple 2015
5.90	Oct 2018	v 5.88 * fixed `resolve/lin` new implementation reportfail bug (jets_new_resolve_enable only) * linderive() introduced (but not used yet) * `unks/TD` uses forceError=true in `vars/1` calls * JetMachine[Consequences] testing script changed (currentdir) * `clear/assignments` is clearing `put/name/tab` properly# current * JetMachine[Consequences] testing script changed (currentdir) * `clear/assignments` is clearing `put/name/tab` properly v 5.89 * run: linear eqs are ALL passed to resolve v 5.90 * jet: option remember bug (multiple eqs problem as reported by JSK) fixed by introducing `eqn/table` * lengthselect introduced	Maple 2015
5.87	May 2017	* not deriving cc's by default (`run/l/extraders` used in slightly different mode) * `run/1` reporting cleanup * Report Reportf macros rewritten, rt, rb no more needed * `size/1/DD` abandoned for a hidden bug * `put/limit/length`, `put/limit/size` instead `put/sizelimit` * JetMachine[Consequences]:-AmICons: Using `AmICons/ignore`() for nonzero(), Varordering() and unknowns()	Maple 15
5.84	Mar 2016	Minor bugfix, linderive() introduced (but not used yet).	Maple 15
5.83	Feb 2016	Important bugfix (compatibility conditions were lost since reduce() was called within run(), resp. storing())	Maple 15
5.82	May 2015	Prior Maple 17, jets may be prettyprinted as subscripts using coordinates(..., separator="__") command	Maple 15
5.81	Mar 2015	Grid computing supported	Maple 15	CZ.1.07/2.3.00/20.0002
5.79	Jun 2013	run() and derive() reimplemented	Maple 14
5.78	October 2012	JetMachine and Consequences packages introduced	Maple 14
5.75	September 2012	Varordering: new orderings implemented	Maple 14
5.71	January 2011	Divideout function improved.	Maple 13
5.7	December 2010	Experimental support for running calculations with multiple variable orderings on multiple threads/computers in parallel.	Maple 13
5.6	February 2010	The new minimal sufficient set of compatibility conditions algorithm implemented.	Maple 13	GACR 201/07/P224 (Baran), MSM4781305904 (Marvan)
5.5	January 2010	The latest version with the old compatibility condition implementation.	Maple 10	GACR 201/07/P224 (Baran), MSM4781305904 (Marvan)
5.0	July 2004	The first Maple 7 and higher implementation.	Maple 7
4.9	December 2003	The first version published here, the only one compatible with Maple V.	Maple V R4 only

See git repository for the details. The main file is mc/Jets.s.

Related projects, extensions and useful links

jTeX is an useful extension for LaTeX-ing of Jets output. Read it in Maple session after Jets.s and enjoy improved latex command.
Distributed Jets project will be a future extension of Jets developed in order to calculate with Jets in parallel on several machines or, at least, to do some calculations which requires human intervention to run automatically.
Nath is a LaTeX style to separate presentation and content in mathematical typography. The style delivers a particular context-dependent presentation on the basis of a rather coarse context-independent notation. Although essentially backward compatible with LaTeX, Nath aims at producing traditional math typography even from sources devoid of aesthetic ambitions. Its name is derived from "natural math notation".
http://www.diffiety.org is another site Jets is available from.
http://gdeq.org is yet another Jets site.

Acknowledgments

During the time of the developement of Jets version 5.5 – 5.6, the ﬁrst-named author was supported by GACR under project 201/07/P224 and the second-named author under project MSM4781305904.

Developement of Jets versions 5.75 – 5.81 was gratefully supported by project CZ.1.07/2.3.00/20.0002.