Hi, My name is Jorge Eduardo Cardona, i'm working rigth now on GSoC with Scilab, my project consist in add a symbolic module to it. In order to do that i had choose GiNaC library for it, and your ToDo list has two topics in which i want to work: Limits and symbolic integration. Well, about integrals i check the source and found a little piece of code that expands integrals (integrals.cpp) and resolve integrals on pow types, and with it solve polynomial integrals. I was thinking in start there to add more methods, but i want to know if there is some work already done. One way could be to add an argument to REGISTER_FUNCTION and pass an integral_func(...) as the extra argument, and we have then integrals for all the functions registered, and we can then start to use more heuristic methods on integrals.cpp, well thats just an initial idea, i want to know all the previous ideas on it to start to work. With limits, i don't even look at the code for it, but this night i will check it. Well, please let me know what do you think about it, you can see a wiki with information in: http://wiki.scilab.org/Gsoc2009Symbolic, and the code on: http://gitweb.scilab.org/?p=symbolic;a=summary. I'm reading some papers on ACM Digital Library about symbolic integration, specially Symbolic integration: the stormy decade, and the one that is linked at the TODO list(that link is actually broken: http://www-sop.inria.fr/cafe/Manuel.Bronstein/publications/issac98.pdf). Well, i really want to add these features to GiNaC and then use it on scilab, please let me know everything about it, what do you expect of it? what basic guidelines on code writing, basic ideas, anything. Bye. -- Jorge Eduardo Cardona jorgeecardona@gmail.com jorgeecardona.blogspot.com ------------------------------------------------ Linux registered user #391186 Registered machine #291871 ------------------------------------------------
Hi, Jorge Cardona schrieb:
Well, about integrals i check the source and found a little piece of code that expands integrals (integrals.cpp) and resolve integrals on pow types, and with it solve polynomial integrals.
I was thinking in start there to add more methods, but i want to know if there is some work already done.
Nobody is working on that part at the moment. The integration code in integral.{h,cpp} is everything that exists.
One way could be to add an argument to REGISTER_FUNCTION and pass an integral_func(...) as the extra argument, and we have then integrals for all the functions registered, and we can then start to use more heuristic methods on integrals.cpp, well thats just an initial idea, i want to know all the previous ideas on it to start to work. With
Sounds good.
I'm reading some papers on ACM Digital Library about symbolic integration, specially Symbolic integration: the stormy decade, and the one that is linked at the TODO list(that link is actually broken: http://www-sop.inria.fr/cafe/Manuel.Bronstein/publications/issac98.pdf).
Another good source might be: O.I. Marichev. Handbook of integral transforms of higher transcendental functions: theory and algorithmic tables. The method outlined in this book is very different from the Bronstein way of doing things, but for a lot of integrands it seems to be the best method. But maybe it is too unwieldy to be implemented in GiNaC (needs quite some tables).
Well, i really want to add these features to GiNaC and then use it on scilab, please let me know everything about it, what do you expect of it? what basic guidelines on code writing, basic ideas, anything.
It'd be great if you could implement such functionality! My expectations are only, that you write using the code style of the GiNaC code base (it should roughly look the same), and that the code is maintainable by other developers as well (keep it easy and documented). Man-power is always limited and code does rot ... Other likely upcoming GiNaC developments are: symbolic summation (expect classes for sums), some code face-lifting in the polynomial/factor sector and polylog code. But nothing of this should interfere with your efforts. Regards, Jens
2009/6/22 Jens Vollinga <jensv@nikhef.nl>
Hi,
Jorge Cardona schrieb:
Well, about integrals i check the source and found a little piece of code that expands integrals (integrals.cpp) and resolve integrals on pow types, and with it solve polynomial integrals.
I was thinking in start there to add more methods, but i want to know if there is some work already done.
Nobody is working on that part at the moment. The integration code in integral.{h,cpp} is everything that exists.
One way could be to add an argument to REGISTER_FUNCTION and pass an
integral_func(...) as the extra argument, and we have then integrals for all the functions registered, and we can then start to use more heuristic methods on integrals.cpp, well thats just an initial idea, i want to know all the previous ideas on it to start to work. With
Sounds good.
I'm reading some papers on ACM Digital Library about symbolic
integration, specially Symbolic integration: the stormy decade, and the one that is linked at the TODO list(that link is actually broken: http://www-sop.inria.fr/cafe/Manuel.Bronstein/publications/issac98.pdf).
Another good source might be:
O.I. Marichev. Handbook of integral transforms of higher transcendental functions: theory and algorithmic tables.
I can't found it, even in amazon is out of stock, do you have it at pdf? could you send it to me?
The method outlined in this book is very different from the Bronstein way of doing things, but for a lot of integrands it seems to be the best method. But maybe it is too unwieldy to be implemented in GiNaC (needs quite some tables).
Well, i really want to add these features to GiNaC and then use it on
scilab, please let me know everything about it, what do you expect of it? what basic guidelines on code writing, basic ideas, anything.
It'd be great if you could implement such functionality! My expectations are only, that you write using the code style of the GiNaC code base (it should roughly look the same), and that the code is maintainable by other developers as well (keep it easy and documented). Man-power is always limited and code does rot ...
Other likely upcoming GiNaC developments are: symbolic summation (expect classes for sums), some code face-lifting in the polynomial/factor sector and polylog code. But nothing of this should interfere with your efforts.
Regards, Jens _______________________________________________ GiNaC-list mailing list GiNaC-list@ginac.de https://www.cebix.net/mailman/listinfo/ginac-list
-- Jorge Eduardo Cardona jorgeecardona@gmail.com jorgeecardona.blogspot.com ------------------------------------------------ Linux registered user #391186 Registered machine #291871 ------------------------------------------------
Hi, sorry for the late reply. Jorge Cardona schrieb:
Another good source might be:
O.I. Marichev. Handbook of integral transforms of higher transcendental functions: theory and algorithmic tables.
I can't found it, even in amazon is out of stock, do you have it at pdf? could you send it to me?
no, sorry, I only have the book from our local library. Regards, Jens
participants (2)
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Jens Vollinga
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Jorge Cardona