- GiNaC-list - ginac.de

Version 0.8.3 is on the wire.
by Richard B. Kreckel 11 May '01

11 May '01

This is from the NEWS file: - color and clifford classes are functional and documented. - New "spinidx" class for dotted/undotted indices. - Predefined spinor metric tensor (created by spinor_metric()). - Symbols can have a LaTeX name, e.g. symbol s("s", "\\sigma"); - LaTeX output of indexed objects is much nicer. - Fix some build-problems (with recent libreadline). (*) - Semantics of arithmetic operators now follows the C++ rules more strictly. (*) Hi Julian! ;-) Enjoy -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/> - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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gTybalt 0.0.4
by Stefan Weinzierl 03 May '01

03 May '01

Dear all, for those who are interested, I put a new version of gTybalt on the web. (http://www.fis.unipr.it/~stefanw/gtybalt.html) gTybalt is a small program build on top of some other packages (GiNaC, TeXmacs, Root, ...) and provides basically TeX-type fonts output for GiNaC and some basic plotting routines. The installation of the new version has become a little bit more user-friendlier, no modifications or adjustment of TeXmacs or GiNaC are needed any more. Enjoy it, Stefan - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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Version 0.8.2...
by Richard B. Kreckel 24 Apr '01

24 Apr '01

...claims to feature the following new stuff: * degree(), ldegree(), coeff(), lcoeff(), tcoeff() and collect() work with non-symbols as the second argument in ginsh. * the argument to collect() can be a list of objects in which case the result is either a recursively collected polynomial, or a polynomial in a distributed form with terms like coeff*x1^e1*...*xn^en, as specified by the second argument to collect(). * Several bugfixes (including a nasty memory leak in .normal()). * class matrix: solve() doesn't call algorithms redundantly any more and inverse() falls back to solve() which works in more general cases. Enjoy -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/> - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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The easter release 0.8.1 has finally landed.
by Richard B. Kreckel 16 Apr '01

16 Apr '01

Hello all, Now let's quickly start finding all those easter eggs that Christian has promised to stuff into the code! This is what's documented in the NEWS file: * degree(), ldegree(), coeff(), lcoeff(), tcoeff() and collect() can now be used with constants, functions and indexed expressions as well, so you can use it to collect by powers of Pi or sin(x), or to find the coefficient of gamma~0. Limitations: - it only works with symbols, constants, functions and indexed expressions, trying to find the coefficient of, e.g., "x^2" or "x+y" won't work; - it does not know about dummy index summations; the coefficient of gamma~0 in p.mu*gamma~mu should be p.0 but is returned as 0; - using coeff(), tcoeff(), lcoeff() or collect() on elements of noncommutative products might return wrong or surprising results. * subs() no longer only substitutes symbols and indices but performs a more general "syntactic substitution", i.e. it substitutes whole objects in sub- expressions. You can subs((a+b)^2,a+b==3) and get 9, but subs(a+b+c,a+b==3) doesn't do anything. Limitations: - substituting numerics (subs(expr, 2==4)) will not replace then in all occurences; in general, you shouldn't substitute numerics, though. * Added preliminary (re)implementations of color and clifford classes. * simplify_indexed(): contraction of symmetric and antisymmetric tensors is zero. * Replaced the various print*() member functions by a single print() that takes a print_context object that determines the output formatting. This should make it easier to add more output types, such as LaTeX output, which is based on work by Stefan Weinzierl. * Added functions to retrieve the properties stored in archive objects outside of unarchive() (for printing or debugging purposes). * Some bugfixes (indexed objects, archive writing). * .collect() on non-polynomials is now algebraically correct. Happy hacking -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/> - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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collect() eats fractions
by Pearu Peterson 12 Apr '01

12 Apr '01

Hi! In ginsh (ginac V0.8.0): > x/(1+x); (1+x)^(-1)*x > collect(x/(1+x),x); 0 <----??? > collect(1+x/(1+x),x); 1 <----??? > collect(x+x/(1+x),x); (1+(1+x)^(-1))*x Is this GiNaC bug or feature? Pearu - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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Is ncmul depreciated?
by Pearu Peterson 09 Apr '01

09 Apr '01

Hi! I have noticed that ncmul(2,a,3) results mul(a,6). Why is this type change ncmul -> mul? Will ncmul be depreciated in future? Pearu - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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failed asertion
by Ben Sapp 29 Mar '01

29 Mar '01

I am trying to use GiNaC in, GNU Octave, an interactive scripting language used primarily for numerical analysis. Below, I provide some output from octave. Can you provide any clues as to what I may be doing to make the following assertion to fail? What can I do to fix it? octave:1> symbols installing ex type at type-id = 18 installing sym type at type-id = 19 installing vpa type at type-id = 20 octave:2> page_screen_output = 0; octave:3> x = sym("x") x = x octave:4> x^2 octave: basic.h:77: GiNaC::basic::~basic(): Assertion `(!(flags & status_flags::dynallocated))||(refcount==0)' failed. -- Ben Sapp Los Alamos National Laboratory email: <mailto:bsapp@lanl.gov> Phone: (505)667-3277 Fax: (505)665-7920 URL: http://www.neutrino.lanl.gov/ -- - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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install on linux with rpm
by richard noel fell 29 Mar '01

29 Mar '01

I am using redhat 7.0. Here is the result of attempting to install ginac via the rpm: [root@rosewall rfell]# rpm -ivh GiNaC-0.7.3-1.i386.rpm GiNaC ################################################## /sbin/ldconfig: /lib/gnulibc1/libiberty.so.1.0 is not a shared object file (Type: 1). [root@rosewall rfell]# What does this error message mean? (I assume it is an error message since ginac is not installed.) Thanks, Dick Fell - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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nonlinear equation systems
by Tilman Utz 28 Mar '01

28 Mar '01

Hello all, possibliy I just missed that one: Is there a method to solve nonlinear systems in Ginac? thanks Tilman - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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For the brave and adventurous...
by Richard B. Kreckel 24 Mar '01

24 Mar '01

...there is some great new compiler food! It's called GiNaC-0.8.0, it is completely fat- and cholesterol-free and available at every good grocery shop next to you. For the not so brave and adventurous, Debian and RedHat pre-cooked servings are expected to follow next week (well maybe). Here is the summary from the NEWS file: * Complete revamp of indexed objects. Instead of multiple classes for indexed things and their indices there is now only one "indexed" class and two types of indices: "idx" for simple indices and "varidx" for indices with variance. There are predefined delta, epsilon and metric tensors, and a function simplify_indexed() that performs canonicalization and dummy index summations. Matrix objects can be indexed for doing simple linear algebra. * Added an option "expand_indexed" to expand() to perform expansion of indexed objects like (a+b).i -> a.i + b.i * Renamed get_indices() to get_free_indices(), which no longer returns dummy indices and checks the consistency of indices in sums. * sqrfree() factorization fixed and improved syntactically. * subs() works on matrices. * Matrices can be constructed from flat list of elements; diagonal matrices can be constructed from list of diagonal elements with diag_matrix(). * Fixed memory leak in expand(). * Operator% for objects of class ncmul has gone. Use operator* now for that case too, which is much more natural. Happy hacking -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/> - To UNSUBSCRIBE, email to ginac-list(a)ginac.de with a subject of "unsubscribe".

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