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cl_F_idecode.cc line 30 ?
by Chris Bouchard 29 Jul '08

29 Jul '08

GiNaC mailing list, I've run across an error with a notification request. The error occurs while trying to archive an expression. The error and request are: "Internal error: statement in file ./float/misc/cl_F_idecode.cc, line 30 has been reached!! Please send the authors of the program a description how you produced this error!" The file cl_F_idecode.cc is in the cln library and a snippet is given here, with a comment indicating line 30: ... namespace cln { const cl_idecoded_float integer_decode_float (const cl_F& x) { floatcase(x , return integer_decode_float(x); , return integer_decode_float(x); , return integer_decode_float(x); , return integer_decode_float(x); ); // this is line 30 } } After playing around with my archive code I'm beginning to think the error occurs when the expression being archived becomes too long. I haven't nailed down a critical expression length but 27 lines works while ~1200 lines generated the error. I can't think of anything else that's changing. The expressions are individual terms from series expansions of expressions returned from xloops function calls (eg. TwoLoop2Pt(...)) and don't contain any noticeably offensive pieces. Sincerely, Chris Bouchard

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Re: [GiNaC-list] comparing symbols
by Chris Bouchard 25 Jul '08

25 Jul '08

Hi, >try the code > >cout << tree << "x = " << x << "\n"; > >then we can see what is going on. x = lst @0x8a08c70, hash=0xc, flags=0x13, nops=2 0 (symbol) @0x8a3df40, serial=62607, hash=0x771ff4, flags=0x7, domain=0 1 (symbol) @0x8a2bde8, serial=62608, hash=0x771ff4, flags=0x7, domain=0 >Maybe r_sum is called with something like > symbol f1("0"); > symbol f2("1"); > r_sum(...,lst(f1,f2),...); Wouldn't that eliminate functional dependence on the variables represented by f1 & f2, making the return value a function of "0" and "1". The end user could handle this by manually simplifying the output, but that wouldn't be optimal. Sincerely, Chris Bouchard

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Re: [GiNaC-list] comparing symbols
by Chris Bouchard 25 Jul '08

25 Jul '08

Hi, >I don't think this situation is possible (modulo compiler bugs and >things like that). > >$ cat test.cc >#include <ginac/ginac.h> >#include <iostream> >using namespace GiNaC; >using namespace std; > >int main(int argc, char** argv) >{ > lst x; > x = ex(0), ex(1); > if (is_a<symbol>(x.op(0))) { > cerr << "Huh, 0 is a symbol?" << endl; > return 1; > } > return 0; >} >$ g++ test.cc -lginac >$ ./a.out >$ echo $? >0 Hmmm... that seems to make sense. For sake of clarity I've pasted code fragment below followed by associated output. Code fragment ------------- ... namespace xloops { static ex r_sum(const ex& t, const lst& b, const lst& x, const ex& eps, int order) { // class of arguments cout << "t is class mul?: " << is_a<mul>(t) << "\n"; cout << "b is class list?: " << is_a<lst>(b)<< "\n"; cout << "b.op(0) is class add?: " << is_a<add>(b.op(0)) << "\n"; cout << "b.op(1) is class numeric?: " << is_a<numeric>(b.op(1)) << "\n"; cout << "x is class list?: " << is_a<lst>(x) << "\n"; cout << "x.op(0) is class symbol?: " << is_a<symbol>(x.op(0)) << "\n"; cout << "x.op(0) is class mul?: " << is_a<mul>(x.op(0)) << "\n"; cout << "x.op(0) is class numeric?: " << is_a<numeric>(x.op(0)) << "\n"; cout << "x.op(0) is class add?: " << is_a<add>(x.op(0)) << "\n"; cout << "x.op(1) is class symbol?: " << is_a<symbol>(x.op(1)) << "\n"; cout << "x.op(1) is class mul?: " << is_a<mul>(x.op(1)) << "\n"; cout << "x.op(1) is class numeric?: " << is_a<numeric>(x.op(1)) << "\n"; cout << "x.op(1) is class add?: " << is_a<add>(x.op(1)) << "\n"; cout << "eps is class symbol?: " << is_a<symbol>(eps) << "\n"; // value of arguments cout << "t = " << t << "\n"; cout << "b = " << b << "\n"; cout << "x = " << x << "\n"; cout << "eps = " << eps << "\n"; ... } Output ------ t is class mul?: 1 b is class list?: 1 b.op(0) is class add?: 1 b.op(1) is class numeric?: 1 x is class list?: 1 x.op(0) is class symbol?: 1 x.op(0) is class mul?: 0 x.op(0) is class numeric?: 0 x.op(0) is class add?: 0 x.op(1) is class symbol?: 1 x.op(1) is class mul?: 0 x.op(1) is class numeric?: 0 x.op(1) is class add?: 0 eps is class symbol?: 1 t = -eps b = {-1/2+eps,1} x = {0,1} eps = eps Is there any other information I could provide to shed light on this? Sincerely, Chris Bouchard

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Re: [GiNaC-list] comparing symbols
by Chris Bouchard 24 Jul '08

24 Jul '08

Hello, >Is it this what you want: > > symbol x; > ex e1 = beta(x, lst(0,1)); > ex e2 = beta(x, lst(4,1)); > > if ( e1 == beta(x, lst(0,1)) ) cout << "e1 BINGO" << endl; > if ( e2 == beta(x, lst(0,1)) ) cout << "e2 BINGO" << endl; > >Otherwise I do not completely understand your problem yet. Could you >clarify it more, then? The x-loops function I'm working with is r_sum. It's definition is (from r.cpp): static ex r_sum(const ex& t, const lst& b, const lst& x, const ex& eps, int order) and I'm trying to flag the occurrence of a certain set of argument values. The boolean operation "is_a<symbol>(x.op(i));" returns 1 for i=0,1 so I think I'm working with a list of symbols, x. Additionally, "cout << x;" yields {0,1} making me think that the symbols have been assigned numerical value. >That is what confuses me. One cannot assign numerical values to symbols >in GiNaC. One can replace symbols by numbers, of course. Perhaps I'm not correctly using/interpreting is_a<class>(ex) and/or cout<<x? Sincerely, Chris Bouchard

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comparing symbols
by Chris Bouchard 24 Jul '08

24 Jul '08

GiNaC discussion list, I'd like to discern when arguments of a pre-defined function (from another library, xloops) attain a certain value. One of the arguments is type: lst x(symbol("a"), symbol("b")); cout << x yields {0,1} and these are the values I'm looking for. I'm unable to define a relational that accurately tests the values attained by a & b. I tried: if (a==0 && ...) if (a.is_equal(0) && ...) if (a.is_zero() && ...) if (match(a,0,lst placeholder) && ...) with no success. "Probably because a is type symbol", I reasoned. So I defined lst y(symbol("c"), symbol("d")); and used in-place modification y[0] = 0; y[1] = 1; to set symbols c and d to 0 and 1, resp. I then tried the conditionals if (x==y && ...) if (x.is_equal(y) && ...) if (match(x,y,lst placeholder) && ...) with no success. How does one set up a conditional for symbols that have been assigned numeric values? Any ideas? Thanks in advance! Sincerely, Chris Bouchard

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ginac-config woe
by naruto canada 23 Jul '08

23 Jul '08

hi Is it possible to resume ginac-config support? I can't get xloops to "configure". I've even tried the cvs version of xloops hoping that it has "kept up" with ginac, but nope. my pkg-config don't support --cppflags either. (which xloops requires) I am trying older versions of GiNac now.

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Re: [GiNaC-list] modify source, run make, then ...
by Chris Bouchard 11 Jul '08

11 Jul '08

Hi, >> If I modify a .cpp source file (say to change a thrown >> error message to pinpoint the location in the code where >> the error is being generated) and then run 'make' within >> the subdirectory containing the .cpp source file to >> generate an updated .o file, do I have to do anything >> else to incorporate my modified error message? > Could you please be more specific? What is exactly > that .cpp file? Is it a part of your program, or GiNaC (or > any other shared library)? The file, r.cpp, is part of another shared library, xloops. >> I think not > It depends. (Sorry, I need to know more details to give a > useful answer). By modifying r.cpp, running 'make' and then running 'make install' the changes made to r.cpp were incorporated (the error message thrown was the modified message). After stumbling upon the solution it appears my original question should have been posted to a beginner's gcc msg board and not GiNaC. Sorry for the clutter. Sincerely, Chris Bouchard

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modify source, run make, then ...
by Chris Bouchard 11 Jul '08

11 Jul '08

GiNaC discussion list, If I modify a .cpp source file (say to change a thrown error message to pinpoint the location in the code where the error is being generated) and then run 'make' within the subdirectory containing the .cpp source file to generate an updated .o file, do I have to do anything else to incorporate my modified error message? I think not but am not getting the updated error message after doing this and I can't find any other instances of the error in the source files. Thanks for your help! Chris Bouchard

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Re: [GiNaC-list] modify source, run make, then ...
by Chris Bouchard 11 Jul '08

11 Jul '08

'make install'... sorry ---- Original message ---- >Date: Thu, 10 Jul 2008 20:39:40 -0500 (CDT) >From: Chris Bouchard <cbouchrd(a)uiuc.edu> >Subject: [GiNaC-list] modify source, run make, then ... >To: ginac-list(a)ginac.de > >GiNaC discussion list, > >If I modify a .cpp source file (say to change a thrown error message to pinpoint the location in the code where the error is being generated) and then run 'make' within the subdirectory containing the .cpp source file to generate an updated .o file, do I have to do anything else to incorporate my modified error message? > >I think not but am not getting the updated error message after doing this and I can't find any other instances of the error in the source files. > >Thanks for your help! >Chris Bouchard >_______________________________________________ >GiNaC-list mailing list >GiNaC-list(a)ginac.de >https://www.cebix.net/mailman/listinfo/ginac-list

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Algebraic sqrt()
by Timo Schlüßler 16 Jun '08

16 Jun '08

Hello, is there a way to compute a sqrt() algebraic? E.g. that sqrt(2) * sqrt(2) gives exact 2 and not 2.0000001 or whatever else. Or that sqrt(45) * sqrt(3) gives sqrt(135) and not the rounded value. thanks in advance, timo

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