Karim Belabas on Fri, 14 Nov 1997 17:48:48 +0100 |
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PARI/GP 2.0.ALPHA |
Announcement of the Pari-2.0.ALPHA release This message is to announce the alpha release of version 2.0 of the PARI/GP system. It can be found at: ftp://megrez.math.u-bordeaux.fr/pub/pari/unix/pari-2.0.alpha.tar.gz For those who do not yet know (?), PARI/GP is a package which is aimed at efficient computations in number theory, but also contains a large number of other useful functions. It is somewhat related to a Computer Algebra System, but is not really one since it treats symbolic expressions as mathematical entities such as polynomials, series, matrices, etc..., and not as expressions per se. However it is often much faster than other CAS, and contains a huge number of specific functions not found elsewhere, essentially for use in number theory. In particular, and especially so in the present release, there is a very large package for working in general algebraic number fields. This package can be used in an interactive shell (GP) or as a C/C++ library (PARI). In addition, it is free! For all questions related to Pari itself, mail to pari@math.u-bordeaux.fr Enjoy! ======================================================================== >From the README file: The ALPHA status means that bugs might still be lurking around, that the documentation might not be absolutely accurate, and that some features or function names might change on short notice. Apart from that word of caution, we believe this version is stable enough to warrant an immediate release. We think it is important for you and for us that you try this new version and send us feedback, since we can then improve the BETA version (scheduled in a few months) and finally the RELEASE version. To save us time and worries, this is a UNIX-only, source-code-only, release. We will provide binaries for later, stabler, versions. ======================================================================== Some NEW features: I) The GP/PARI structure has been cleaned up. * The whole configuration process has been automated, and a Configure file is provided. Just typing 'Configure' should see you home in most cases. * PARI is now available as a dynamic library, thanks to Louis Granboulan. (you can link gp with it should you wish to). This saves a tremendous amount of disk space, and is generaly more convenient as you don't need to re-link your files when updating the library (or when debugging. or profiling, or...). * types now have a symbolic mnemotechnic name (e.g t_INT for an integer, t_VEC for a vector, and so on). * General speed-up (depends on your applications, about 20% for our generic testing file). * Experimental module loading structure (the actual function tree has not yet been cut into modules, but for the GP specific functions). II) Many new or improved functions in the PARI library. * MANY class-field related functions. In particular: - is it now possible to try and remove the GRH assumption on class group computations. - ray class groups computations (including discrete log). - explicit defining equations in simple cases (Kummer extensions of prime degree, quadratic base field). * roots is now entirely reliable, thanks to Xavier Gourdon. * some core routines have been optimized: Karatsuba fast multiplication, a specific function gsqr() for squarings (twice as fast as gmul(x,x) in the most favourable cases),... * input/output is much more flexible now: - a function GENtostring has been added, generalizing gitoascii to any PARI object (with a simpler syntax: GENtostring(g) returns a malloced string containing g as gp would print it). - lisexpr has a relative flisexpr (for filtered lisexpr), which enables you to use input containing whitespaces. - you can use GENs in formatted output, a la printf. * improved garbage collecting. * private variables can be created without an explicit lisexpr(), using fetch_var() and delete_var(). III) GP has been completely re-written: * lowercaps/uppercaps are now significant. All predefined constants (Euler, I, Pi) have been renamed (as well, the o() notation for series and padics has been superseded by O()). for (i=1,10, print(i)) will not yield an error anymore. * human-readable error messages, including a caret to indicate where a GP syntax error occured. * function names were renamed according to a more logical scheme. The file new.dico provides a translation (available under GP using "whatnow") * You can retrieve basic information from complicated objects using member functions (you cannot define your own, though). For instance x.disc will yield the discriminant of x, whether it was created by nfinit (aka initalg), bnfinit (aka buchinit), ellinit (aka initell). * A .gprc file is available to set "permanent" defaults (such as global variables, aliases, common functions, etc...). For instance, you can put all your scripts in some special directories, and point them out to GP using "path". See lib/gprc.default for examples. The function "default" enables to change most defaults under gp. For instance: default(compatible,2) will give you back the former gp function names and helpmessages. (default(compatible,3) undoes the lowercaps/uppercaps changes as well). Try "default". * the basic C idiosyncrasies such as for instance i++ (for i=i+1), i<<1 (for left shift) or i+=j (for i=i+j) are now allowed within GP scripts. /* */ multi-line comments are understood. * lists and (primitive) string support have been added. Characters can be quoted with the usual meaning. For instance, try default(prompt,"\e[1mgp\e[m > ") As a result, set functions can now be used with arbitrary elements. * if your terminal supports color (variants of color_xterm for instance), you can tell GP to highlight its output in different (user configurable) colors. This is done by fiddling with the default "colors". * The familiar functions "break", "next" and "return" are now available. These should supersede the buggy label/goto provided in old versions of GP. * somewhat enhanced on-line help. Even more: if you have perl on your system, try ?? function-name (?? bnfinit for instance). This is provided by external scripts which can be used independently, outside of any GP session. * If readline is installed on your system, a context-dependent completion (not yet user-programmable) is now available (try hitting <TAB> here and there). Try ?? readline. * many functions now have default arguments (shown between braces {} in the on-line description). gp first reads user-supplied arguments, and then fills in the arg list with these default values. Optional args can be entirely omitted, comma included (for a function with no mandatory arguments, even parentheses are optional !). For instance: Mat = Mat() bnfclassunit(x^2+1,0) = bnfclassunit(x^2+1) bnfclassunit(x^2+1,,[0.2,0.2]) = bnfclassunit(x^2+1,0,[0.2,0.2]) The "else" part of the "if" function can be entirely omitted. if (a,1) is now correct; of course, the former syntax if (a,1,) is still valid. * functions "extern" and "system" have been added to interface with external programs (UNIX only). You can do for instance extern("myprog"), or system("ls -l *.gp"). * even better, "install" enables you to load any function provided by a dynamically linked library, and have the GP interpreter use it. This makes it easy to have your own customized version of GP with your own set of functions on startup (you can document them using "addhelp"). * On 32-bit machines, maximum number of variables has been increased from 254 to 16382. Arrays can have up to 16777215 elements (instead of 65535). In addition vector/matrix operations in GP now perform orders of magnitudes faster than in version 1.39 ============================================================================= -- Karim Belabas e-mail: Max-Planck-Institut fuer Mathematik karim@mpim-bonn.mpg.de Gottfried-Claren-Str. 26 tel: 53225 Bonn (Germany) (00 49 228) 402-245