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Removed runtime dependence on libmpfr; DrDr should be able to test all but tests/bigfloat-test.rkt now

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This commit is contained in:
Neil Toronto 2012-11-16 15:38:15 -07:00
parent d1a02d3fe2
commit 97fa28552d
1 changed files with 3 additions and 4 deletions
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7
collects/math/private/flonum/expansion/expansion-log.rkt
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@ -7,8 +7,7 @@ Both implementations do some argument reduction, find excellent 53-bit initial e
perform one Newton step.
|#
(require "../../../bigfloat.rkt"
"../flonum-functions.rkt"
(require "../flonum-functions.rkt"
"../flonum-syntax.rkt"
"../flonum-log.rkt"
"expansion-base.rkt"
@ -29,6 +28,8 @@ A value of k that reduces any x to [0.5, 1.0] is
k = -truncate(log(x)/log(2))
|#
(define-values (log2-hi log2-lo) (values 0.6931471805599453 2.3190468138462996e-17))
(: fl2log-reduction (Flonum Flonum -> (Values Flonum Flonum Flonum)))
(define (fl2log-reduction x2 x1)
(define k (- (fltruncate (fl/ (fllog+ x1 x2) (fllog 2.0)))))
@ -79,8 +80,6 @@ A `k' that reduces any argument `x' to (-1/2,1/2) is
k = round(log1p(x)/log(2))
|#
(define-values (log2-hi log2-lo) (bigfloat->fl2 log2.bf))
(: fl2log1p-reduction (Flonum Flonum -> (Values Flonum Flonum Flonum)))
(define (fl2log1p-reduction x2 x1)
(define-values (a2 a1) (fl2+ x2 x1 1.0))