From: Stephan F. <cri...@cs...> - 2013-04-20 16:56:58
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Well, if it helps with your decision process: I have a mostly complete GMP connection for SBCL (currently only for integers, though rationals should be easy to extent; that's my next step). It was a project I had considered for a longer time already and Paul's GSoC description sparked my interest anew. I have kept it under wraps so far (apart from some communication with Paul) because I didn't want to discourage a potential student from participating in GSoC. However, looking at my project schedule at work there are several things from Pauls project suggestion that will definitely not happen by me in the foreseeable future: extensive unit tests; GMP algorithms in Lisp for SBCL. So you might want to expand on that or take on your MPFR proposal. Regs, Stephan On 04/20/2013 06:11 PM, Akshay Srinivasan wrote: > I wonder if I can pitch the MPFR integration itself as a project for > GSoC; I'm afraid this is what I'd want SBCL to have more (well the > bignums are already there :), but also that it is of a much lower > priority than adding GMP support. > > Akshay > > > On 20 April 2013 03:00, Paul Khuong <pv...@pv... <mailto:pv...@pv...>> wrote: > > Stephan Frank wrote: > > but wouldn't a library with bindings to MPFR (using CFFI) not > make more > sense? Maxima (and I suppose matlisp as well) have to implement > their > own bigfloats data type anyway whereas the GMP integration has the > chance of being tightly and transparently integrated with the > underlying > bignum implementation of SBCL. I could only see an advantage when > tightly coupling it with CMUCL's quad-floats. > > > We may still do something useful with long-floats. That type is > currently equivalent to double-float, but there's nothing that makes > the situation necessary. IIRC, CLISP's long floats are arbitrary > precision. I'm not completely sure what that means for standard > compliance, but I'm also somewhat open to interpreting the standard > loosely if the looseness only affects long float values. > > However, integrating MPFR for long floats is likely to be more work > than plugging GMP in SBCL's bignums. We'd have to re-create a > long-float type, likely fiddle with numeric bounds propagation, and > (this final part is much more easy) define a concrete representation > for long floats and tell the GC about. > > Paul Khuong > > > > > ------------------------------------------------------------------------------ > Precog is a next-generation analytics platform capable of advanced > analytics on semi-structured data. The platform includes APIs for building > apps and a phenomenal toolset for data science. Developers can use > our toolset for easy data analysis & visualization. Get a free account! > http://www2.precog.com/precogplatform/slashdotnewsletter > > > > _______________________________________________ > Sbcl-devel mailing list > Sbc...@li... > https://lists.sourceforge.net/lists/listinfo/sbcl-devel > |