Commit Graph

14 Commits

Author SHA1 Message Date
Neil Toronto
aed3b39546 Added flexp2', fllog2', `fllogb'; refactored and documented flonum testing
Note: With this refactoring, `math/utils' no longer depends on `rackunit'.

* (flexp2 x) computes (flexpt 2.0 x) but in about 1/3 the time for integer
  `x' using a lookup table. Written for exact argument reduction in `fllog2'
  after discovering that (flexpt 2.0 x) was the main performance bottleneck.

* (fllog2 x) computes (/ (fllog x) (fllog 2.0)) with near perfect accuracy.
  Invented an algorithm to compute it with at least 8 extra bits before
  final rounding; quite pleased with the result. Needed `fllog2' to ensure
  (fllogb 2.0 x) would be exact when `x' is a power of two.

* (fllogb b x) computes (/ (fllog x) (fllog b)) with better accuracy, and
  also handles limit values in a way that's consistent with the mathematical
  limits. When those are ambiguous, it's consistent with `flexpt', which
  follows IEEE 754 and C99. Otherwise returns +nan.0. See docs for details.

* `bflogb' is currently just for testing `fllogb'.

* Refactored FPU testing and documented it. So far, the only documented way
  to do it is by calling `test-floating-point', which runs a comprehensive
  deterministic+randomized suite of tests and returns a list representing
  failed tests. I'll document individual tests after I document flonum
  expansions and result/error functions like `fl+/error'.

* Added `fllog2' and `fllogb' to the flonum tests.
2013-01-28 17:44:33 -07:00
Neil Toronto
564f589601 Fixed some limits and accuracy issues with flonum expansions 2013-01-19 18:09:44 -07:00
Neil Toronto
e55a31480e Precise flonum tests (error usually must be <= 0.5 ulp), and prerequisite
additions/changes

* More accurate `flulp-error'

* Added `flonum->fields', `fields->flonum', `flonum->sig+exp',
  `sig+exp->flonum' (currently undocumented)

* Correctly rounded, robust `bigfloat->fl2' and `fl2'

* Correctly rounded, robust `fl+/error', `fl-/error', `fl*/error',
  `flsqr/error', `fl//error'

* Much faster but slightly less accurate fl2 ops (shamelessly stolen from
  crlibm, which is LGPL)

* Added `fl2ulp', `fl2ulp-error', `fl2?' (which detects overlap),
  `+max-fl2-subnormal.0' (which was tricky), `fl2abs'

* Added deterministic and randomized flonum op tests (against MPFR)

* Added deterministic and randomized flonum/error op tests (against MPFR)

* Added deterministic and randomized fl2 op tests (against MPFR)

* Exposed FPU tests in `math/utils' (currently undocumented)
2012-12-27 17:30:04 -07:00
Neil Toronto
60dd8d065f Fixes for errors Pierpaolo Bernardi found by reviewing the docs; also,
renamed `partition-count' to `partitions' to be consistent with
`permutations', and gave better examples in `multinomial' docs

 * (flulp-error +inf.0 +nan.0) was returning +nan.0 instead of +inf.0

 * Type of `multinomial' didn't match its docs or `flmultinomial'

 * Reworded docs for `diagonal-array'

 * Reworked/reordered quite a few things in docs for `math/bigfloat'

 * Fixed first identity given in `gamma-inc' docs

 * Fixed descrption for `+max.0', etc.
2012-12-17 11:40:37 -07:00
Neil Toronto
055512b4e8 Renamed make-flexp/base' to make-flexpt'
Renamed `dist' struct type to `distribution' ("dist" is too common)
2012-12-03 22:45:31 -07:00
Neil Toronto
5a43f2c6bc Finished array documentation!
Cleaned up other docs in preparation for alpha-testing announcement

Created `math/utils' module for stuff that doesn't go anywhere else (e.g.
FFT scaling convention, max-math-threads parameters)

Reduced the number of macros that expand to applications of `array-map'

Added `flvector-sum', defined `flsum' in terms of it

Reduced the number of pointwise `flvector', `flarray' and `fcarray' operations

Reworked `inline-build-flvector' and `inline-flvector-map' to be faster and
expand to less code in both typed and untyped Racket

Redefined conversions like `list->flvector' in terms of for loops (can do
it now that TR has working `for/flvector:', etc.)
2012-11-29 15:45:17 -07:00
Neil Toronto
6009eed8d2 Moved flvector functions into math/flonum
Sped up normal distribution sampling procedure (2x for large samples)
2012-11-29 15:45:17 -07:00
Neil Toronto
7aadf33ead Implemented `flmultinomial' (not accurately, but it's there); changed
argument types to match `multinomial'
2012-11-29 15:45:16 -07:00
Neil Toronto
6f1ffecc23 Stubbed out missing math/array' and math/statistics' doc entries to
clean up build

Moved `float-complex?' and `number->float-complex' to `math/base',
documented them

Documented `flexpt1p'

Removed `samples->immutable-hash' (not covariant anyway; not going to
use hashes)
2012-11-27 18:05:38 -07:00
Neil Toronto
2d34811ab6 Finished `math/distributions' documentation!
Fixed a few limit cases in some distributions (e.g. (uniform-dist 0 0) didn't
act like a delta distribution, (beta-dist 0 0) and (beta-dist +inf.0 +inf.0)
pretended to be defined by unique limits even though they can't be)

Made integer distributions' pdfs return +nan.0 when given non-integers

Added "private/statistics/counting.rkt", for hashing and binning samples

Added `flvector-sums' (cumulative sums with single rounding error)

Added `flinteger?', `flnan?' and `flrational?', which are faster than their
non-flonum counterparts (at least in Typed Racket; haven't tested untyped)
2012-11-27 13:44:15 -07:00
Neil Toronto
0936d8c20b Reworked distribution API, finally happy with it (as happy as I can be without being able to partially instantiate polymorphic parent struct types)
Added docs for math/distributions (about 75% finished)
Started docs for math/array (very incomplete)
2012-11-21 21:16:35 -07:00
Neil Toronto
1e52736089 Documentation style changes
Fixes after merge weirdness from pull request (specifically, removed `bfrandom' from "mpfr.rkt" again)
Removed dependence of math/flonum on math/bigfloat (better build parallelization)
Changed `divides?' to return #f when its first argument is 0
Made return type of `quadratic-character' more precise
Made argument types more permissive:
 * second argument to `solve-chinese'
 * second argument to `next-primes'
 * second argument to `prev-primes'
2012-11-17 21:02:37 -09:00
Neil Toronto
97fa28552d Removed runtime dependence on libmpfr; DrDr should be able to test all but tests/bigfloat-test.rkt now 2012-11-16 15:39:15 -07:00
Neil Toronto
f2dc2027f6 Initial math library commit. The history for these changes is preserved
in the original GitHub fork:

  https://github.com/ntoronto/racket

Some things about this are known to be broken (most egregious is that the
array tests DO NOT RUN because of a problem in typed/rackunit), about half
has no coverage in the tests, and half has no documentation. Fixes and
docs are coming. This is committed now to allow others to find errors and
inconsistency in the things that appear to be working, and to give the
author a (rather incomplete) sense of closure.
2012-11-16 11:39:51 -07:00