Woah, this is very impressive! And now I can convince more people to use Racket! <div class="gmail_extra"> <div class="gmail_quote">On Fri, Dec 7, 2012 at 9:33 PM, Neil Toronto <<a href="mailto:neil.toronto@gmail.com" target="_blank">neil.toronto@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">I've just pushed the last commits that make the new math library ready for wider testing. Almost everything ready for use is documented, the tests keep passing, and everything *seems* to work. We (the Racket development team) need people to use the heck out of it, to find the majority of the remaining logic and design errors before the next release. This is a big chunk of new code - ~20k lines in ~100 nontrivial files - so the more eyes, the better. If all you have time for is checking documentation, we'll take it. The latest docs are here: <a href="http://pre.racket-lang.org/docs/html/math/" target="_blank">http://pre.racket-lang.org/docs/html/math/</a> The nightly builds are here: <a href="http://pre.racket-lang.org/installers/" target="_blank">http://pre.racket-lang.org/installers/</a> For Windows and Mac, the nightlies should include two new libraries used by `math/bigfloat': libgmp and libmpfr. Linux users almost certainly already have them; many packages (e.g. gcc) depend on libmpfr. If you prefer to build from source, clone the git repository here: <a href="https://github.com/plt/racket" target="_blank">https://github.com/plt/racket</a> If you're building on Windows or Mac, you can download pre-built libgmp and libmpfr from here: <a href="http://download.racket-lang.org/libs/10/" target="_blank">http://download.racket-lang.org/libs/10/</a> ************ Once you have a pre-release build, do (require math), and away you go! Well, it's probably not obvious where to start. The following are the modules that `math' re-exports, and for some, what needs testing. Please feel free to skim. In decreasing order of attention they need: (require math/array) NumPy/SciPy/Repa-like arrays, Typed-Racket-style. Provides a covariant `Array' type and several mutable subtypes, array literals, functional constructors, pointwise operations with automatic broadcasting in SciPy/NumPy or permissive mode, slicing, indexing tricks, folds, easy arbitrary transformations, and parallel FFT. This one needs a lot of usability testing. In particular... We're trying something that's been done only once before, in Haskell's Repa: by default, arrays' elements are *non-strict*, meaning that they're recomputed when referenced. Cool things about this: pretty much everything can in principle be parallelized, and most intermediate arrays use almost no memory. But it requires more thought from users about when arrays should be made strict (computed and stored all at once). If it totally sucks, we can change it. If it's a worthwhile imposition, we'll leave it. If it's a wash, we could parameterize the default behavior. Also, I've been considering allowing negative axis numbers and row indexes. Need feedback on how helpful it would be vs. confusing and error-hiding. Lastly, I'm looking for a dual of `array-axis-reduce' (a kind of fold) that makes it easy to write `list-array->array', the inverse of the existing `array->list-array'. If you're into functional design puzzles, give this one a shot. (require math/bigfloat) Floating-point numbers with arbitrarily large precision and large exponents. Also elementary and special functions, whose results are proved to be correct in many theses and dissertations. This is a Racket interface to MPFR (<a href="http://www.mpfr.org" target="_blank">www.mpfr.org</a>). This module needs platform-specific testing. I think we've verified that `math/bigfloat' works on all the supported 64-bit platforms, but not whether it works on supported 32-bit platforms. It should. ;) There's an error in the current nightly build, which causes an infinite loop when libmpfr isn't installed and a bigfloat function is applied. I just pushed a fix; it should fail properly tomorrow. (require math/distributions) Probability distributions: discrete, integer-valued and real-valued. Distribution objects can compute pdfs, cdfs and inverse cdfs, optionally in log space, and for cdfs and inverse cdfs, optionally for upper tails. They can also generate samples. Design ideas are welcome. More distributions are planned. Let me know which you need, and I'll concentrate on those first. Watch out, R. Our gamma cdf is more accurate. (require math/special-functions) Non-elementary functions like gamma, erf, zeta, Lambert W, and incomplete gamma and beta integrals. Most of these should be fairly accurate; i.e. they compute answers with apparently < 5 ulps error for the majority of their domains. But floating-point domains are huge, so the more use, the better. (require math/number-theory) Number theory! Chinese Remainder solutions, coprimality and primality testing, factorization, congruence arithmetic parameterized on a current modulus, integer nth roots, multiplicative functions, common number sequences (Bernoulli, Eulerian, tangent, etc.), combinatorics, primitive roots, and more. Please thank Jens Axel Søgaard, who wrote this module, for his excellent work. (require math/statistics) Functions to compute summary values for collections of data, and to manage weighted samples. Every function for which it makes sense accepts weighted values, including the O(1)-space running statistics update. I'm in the middle of documenting this. I'll get around to documenting correlation, kth-value order statistics (via quickselect), and counting/binning at least by Dec. 18. (require math/flonum) Re-exports `racket/flonum' along with many more floating-point goodies. If you're a floating-point nut, you'll love it. If you're not, at least check out `flsum'. If you're doing statistics, look into log-space arithmetic (`lg+' and friends). (require math/base) Re-exports `racket/math'; also exports some more constants like gamma.0 (Euler-Mascheroni), a bit more float-complex support, inverse hyperbolic functions, large random numbers, error measurement. Lastly, there's `math/matrix', which is currently not re-exported by `math' because I haven't reviewed it yet. This is more from Jens Axel, and if it's like his other fine work, it's correct and well-tested. I'll probably get to it by Christmas. To sum up, there are 8 modules that need pounding on, and we need YOU to do some pounding. If you're not terribly busy, please pick one that looks interesting/fun/useful, and try it out. Thanks! Neil ⊥ ____________________ Racket Users list: <a href="http://lists.racket-lang.org/users" target="_blank">http://lists.racket-lang.org/users</a> </blockquote></div> </div>