- GiNaC-devel - ginac.de

Most elegant way to get from (ex) to (void *)?
by Duraid Madina 14 Aug '01

14 Aug '01

Hi all, What's the most elegant way (okay, fastest way) to translate between expressions and plain-old arrays of bytes? (of course, I am interested in both directions!) Right now I've got a really kludgy system that takes the expression, 'archives' it, sends that archive into an 'strstream' buffer, and then grabs the 'string' backing that strstream, et voila. Any better ideas? ;-) Thanks in advance, Duraid

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ex_to templates
by Pearu Peterson 12 Aug '01

12 Aug '01

Hi! Since ex_to_*() are announced deprecated with the corresponding replacements ex_to<*>() then what about ex_to_nonconst_*()? Will there be ex_to_nonconst<*>()? It just seems logical to have ones. Regards, Pearu

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GiNaC memory leak?
by Marko Riedel 09 Aug '01

09 Aug '01

Greetings. I am sending some code that I wrote in order to solve a differential equation. You run the compiled program with a command-line argument telling it what terms to use. Interesting values are e.g. 10, 14, 16 and 19. (The higher values take some time to compute.) Warning! When you run the program on the higher values, it starts consuming huge amounts of memory. On a SuSE Linux machine the OS eventually kills the process. What is going on here? The program solves a system of equations with a 1000 x 1000 approx. coefficient matrix. What is all the memory being used for? Take, say 32 bytes per entry; the system should then allocate about 32M of memory. In fact it tries to allocate more than 512M of memory! Best regards, Marko Riedel ---------------------------------------------------------------------- #include <stdio.h> #include <fstream> #include <ginac/ginac.h> using namespace std; using namespace GiNaC; static symbol u("u"); static symbol z("z"); static symbol l1("l1"); static symbol l2("l2"); static symbol phi("phi"); static void extracteqs(ex eq, lst *l) { int i, j; ex c1, c2; for(i=eq.ldegree(z); i<=eq.degree(z); i++){ c1=eq.coeff(z, i); for(j=eq.ldegree(u); j<=eq.degree(u); j++){ c2=c1.coeff(u, j); if(is_ex_of_type(c2, numeric)){ if(c2!=0){ cerr << "inconsistency: " << i << " " << j << endl; exit(-1); } } else{ (*l).append(c2==0); cerr << (*l).nops() << endl; } } } } int main(int argc, char **argv) { int maxcoeff, i, j; if(argc!=2){ cout << argv[0] << " <maxcoeff>" << endl; exit(-1); } sscanf(argv[1], "%d", &maxcoeff); if(maxcoeff<1){ cout << "argument " << maxcoeff << " out of range" << endl; exit(-2); } ex rt, lf1, lf2; lst vs; rt=0; lf1=0; lf2=0; for(i=0; i<maxcoeff; i++){ for(j=0; j<maxcoeff; j++){ symbol a; rt+=a*pow(z, i)*pow(u, j); vs.append(a); if(i<maxcoeff-6 && j<maxcoeff-6){ symbol b, c; lf1+=b*pow(z, i)*pow(u, j); lf2+=c*pow(z, i)*pow(u, j); vs.append(b); vs.append(c); } } } cerr << rt << endl; cerr << lf1 << endl; cerr << lf2 << endl; cerr << vs << endl; ex s, sf, sf1, sf2; sf=pow(1-u, 11)*pow(1-z, 7)*pow(1-z*u, 7); sf1=pow(1-u, 9)*pow(1-z, 5)*pow(1-z*u, 5); sf2=pow(1-u, 10)*pow(1-z, 2)*pow(1-z*u, 2); s=rt/sf1+ lf1*u*log(1/(1-z))/sf2+ lf2*log(1/(1-z*u))/sf2; ex f, rz, rzv, rzu, rzvu; f=(u-u*u*z*z)/pow(1-z, 2)/pow(1-z*u, 2); rz=1/pow(1-z, 2); rzv=1/pow(1-z, 2); rzu=rz.subs(z==z*u); rzvu=rzv.subs(z==z*u); ex t1, t2, t3, t4, t5, t6, t7, t8, t9; t1=6*u*u*rzu *f; t2=6*u*u*rzvu*f; t3=6*u*u*rzu *phi; t4=6*u*u*rzu *rz; t5=6*u*u*rzvu*rz; t6=6*u*u*rzu *rzv; t7=6* rz *f; t8=6* rzv *f; t9=6* rz *phi; ex rhs1, rhs2; rhs1=(t1+t2+t4+t5+t6+t7+t8).normal(); rhs2=(t3+t9).normal(); ex eq, eq1; eq=(s.diff(z, 2)-rhs1-rhs2.subs(phi==s)) .subs(lst(log(1/(1-z))==l1, log(1/(1-z*u))==l2)) .expand(); eq1=0; for(i=0; i<eq.nops(); i++){ eq1+=(eq.op(i)*sf).normal().expand(); cerr << "expand: " << i << " " << eq.nops() << endl; } ex leq1=eq1.coeff(l1, 1), leq2=eq1.coeff(l2, 1); eq1=eq1.subs(lst(l1==0, l2==0)); lst ceqs; ex s0=(s.subs(z==0)*pow(1-u, 9)).normal(); ex sz0=(s.diff(z).subs(z==0)*pow(1-u, 9)).normal(); ex i0=(u*pow(1-u, 9)).expand(); ex iz0=((4*u+4*u*u)*pow(1-u, 9)).expand(); cerr << "extract initial: 1" << endl; extracteqs(s0-i0, &ceqs); cerr << "extract initial: 2" << endl; extracteqs(sz0-iz0, &ceqs); cerr << "extract: 1" << endl; extracteqs(eq1, &ceqs); cerr << "eqs: " << ceqs.nops() << endl; cerr << "extract: 2" << endl; extracteqs(leq1, &ceqs); cerr << "eqs: " << ceqs.nops() << endl; cerr << "extract: 3" << endl; extracteqs(leq2, &ceqs); cerr << "eqs: " << ceqs.nops() << endl; ex sl; cerr << "solving: " << ceqs.nops() << " " << vs.nops() << " ..." << endl; try{ sl=lsolve(ceqs, vs); } catch(exception &e){ cerr << e.what() << endl; exit(-3); } cout << sl << endl; lst zlist; for(i=0; i<vs.nops(); i++){ zlist.append(vs.op(i)==0); } ex result; result=s.subs(sl).subs(zlist); cout << result << endl; archive a; a.archive_ex(result, "result"); char fname[80]; sprintf(fname, "fixedpoints%d.gar", maxcoeff); ofstream out(fname); out << a; out.close(); }

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Re: GiNaC/ginsh ginsh_parser.yy
by Richard B. Kreckel 08 Aug '01

08 Aug '01

This patch... On Tue, 7 Aug 2001, Christian Bauer wrote: > Update of /home/cvs/GiNaC/ginsh > > Modified Files: > ginsh_parser.yy > Log Message: > - increased compatibility with RedHat's readline-4.2-1 package ...has broken compatibility with Readline 4.1 on all our Debian Potato boxen. I've looked into it but don't understand one thing: why were there changes necessary in sections that should be #ifdef'ed out when compiling with libreadline-4.2? Christian, can you fix this? Regards -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/> <swear> This libreadline nightmare makes me slightly sick. Why does the maintainer not release 4.3 *with* fine-grained version control before 4.2 screws up all upcoming Distros? And then there is the C++-brokenness. SuSE did not get it right. They seem to ship with two libreadlines now and compile all their stuff to the old one! Debian fixed it only after agonizing for a few weeks. Let's hope RedHat get's it right now. </swear>

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A move away from CLN?
by Duraid Madina 02 Aug '01

02 Aug '01

Hi all, Please forgive my ignorance, but is there any chance GiNaC might move away from CLN and in its place use a "softer" library such as NTL? (http://www.shoup.net/ntl/) At least then we might have a chance of moving away from (or at least not kneeling before) Mark Mitchell and his GCC henchmen ;-) What sort of obstacles would such a 'port' face? Just how many innocent undergrad students would need to be tortured for such a feat to occur? Disappointed with GCC, (albeit deleriously happy with GiNaC) Duraid

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GiNaC 0.9.2 around
by Alexander Frink 31 Jul '01

31 Jul '01

Hi all, I apologize for the laziness of my co-workers who produced no more than 3 entries in the news section for GiNaC 0.9.2. But ok, it is summer time and very hot in Germany, so we hope to be more productive again in the future... Forced to write something before they let me go to the next beer-garden Alex * Epsilon tensor is more functional. * simplify_indexed() is better at detecting expressions that vanish for symmetry reasons. * Several little bugfixes and consistency enhancements. -- Alexander Frink E-Mail: Alexander.Frink(a)Uni-Mainz.DE Institut fuer Physik Phone: +49-6131-3923391 Johannes-Gutenberg-Universitaet D-55099 Mainz, Germany

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Re: GiNaC/ginac clifford.cpp
by Do Hoang Son 30 Jul '01

30 Jul '01

Hi, There still has a bug somewhere in simplify_index(). Look at this case: ex dt = dirac_slash(p1, D) + m1* dirac_ONE(); ex db = dirac_slash(p2, D) + m2* dirac_ONE(); cout << (dt*dirac_gamma5()*db*dirac_gamma5()).simplify_indexed()<< endl; It returns: -m2*p1\-p1\*p2\-m2*ONE*m1-p2\*m1 The correct one should be: m2*p1\-p1\*p2\+m2*ONE*m1+p2\*m1 It seems that GiNaC does: dirac_gamma5()*dirac_ONE() = -dirac_ONE()*dirac_gamma5() Cheers, Son

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3/5 vs. \frac{3}{5}
by Richard B. Kreckel 13 Jul '01

13 Jul '01

Do Hoang Son just raised the issue why in print_latex context rationals are not typeset as \frac{3}{5} but instead as plain 3/5. Before implementing this I would like to ask if anybody is having an objection? Regards -richy. -- Richard Kreckel <Richard.Kreckel(a)Uni-Mainz.DE> <http://wwwthep.physik.uni-mainz.de/~kreckel/>

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Indices and differentiation. CLN.
by Marko Riedel 11 Jul '01

11 Jul '01

Greetings. Two questions: 1. Could you make precompiled CLN library binaries for Linux (RPM format) available somewhere on the web? 2. What is wrong here? I downloaded and installed GiNaC-0.9.1-1.i386.rpm from ftp://ftpthep.physik.uni-mainz.de/pub/GiNaC/rpm/ and I downloaded and compiled cln-1.1.1.tar.gz. riedel@linuxfast:qselav > cat test.cpp #include <stdio.h> #include <ginac/ginac.h> using namespace std; using namespace GiNaC; static symbol g("g"); static symbol z("z"); int main(int argc, char **argv){ ex T; T=indexed(g, idx(3, 1))*pow(z, 3); cout << T.diff(z) << endl; } riedel@linuxfast:qselav > c++ test.cpp -o testdiff -lcln -lginac /usr/local/lib/libginac.so: undefined reference to `__dynamic_cast_2' collect2: ld returned 1 exit status riedel@linuxfast:qselav > ls -l /usr/local/lib/libginac.so lrwxrwxrwx 1 root root 26 Jul 11 20:24 /usr/local/lib/libginac.so -> /usr/lib/libginac-0.9.so.1 riedel@linuxfast:qselav > Best regards, Marko Riedel

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Factorization
by Wolfgang Abele 10 Jul '01

10 Jul '01

Hi everyone, can you tell me what's the current situation regarding polynomial factorization in GiNaC? According to your wishlist, it's still missing, but I've just read some mails in this list saying that some people are working on the task. I'm a student of mathematics, and my diploma thesis is about polynomial factorization. I'm interested in both factorization in Z[x] and algebraic extensions, and I wonder if I could implement some algorithms or contribute to any ongoing projects. Wolfgang By the way, I've found out how to declare a polynomial ring over modular integers in CLN, so I don't need an example any more.

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