This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "CMU Common Lisp". The branch, master has been updated via 5f81e24180fa7721fcad38b9ae3419bd9f2a221d (commit) from 46b8066952521e9d7c43ff101677725425c851a8 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- commit 5f81e24180fa7721fcad38b9ae3419bd9f2a221d Author: Raymond Toy <toy.raymond@gmail.com> Date: Sun Nov 30 18:24:59 2014 -0800 Fix to handle (log 3/2 2) and (log -3/2 2). Test added. * src/code/irrat.lisp: * Fix LOG2 to handle the case of negative rational numbers. * Fix LOG of rational to a rational base. We want to convert the log of the number to a single float because log2 isn't intended to handle single-float type. * tests/irrat.lisp: * Add test for log of rational to rational base. * Add some additional tests for dd-%log2. diff --git a/src/code/irrat.lisp b/src/code/irrat.lisp index 0804ef9..b21b92f 100644 --- a/src/code/irrat.lisp +++ b/src/code/irrat.lisp @@ -632,8 +632,11 @@ ;; it, and converting it to double-float is accurate. (if (= (integer-length top) (integer-length bot)) - (/ (log1p (float (- x 1) float-type)) - (log-of-2 float-type)) + (let ((log-abs (/ (log1p (float (- (abs x) 1) float-type)) + (log-of-2 float-type)))) + (if (minusp x) + (complex log-abs (log-2-pi float-type)) + log-abs)) (multiple-value-bind (top-n top-frac) (log2-bignum top) (multiple-value-bind (bot-n bot-frac) @@ -687,10 +690,10 @@ (float (%log2 (float number 1d0)) 1f0)) (((foreach integer ratio) (foreach integer ratio single-float)) - (log2 number 1f0)) + (float (log2 number) 1f0)) (((foreach integer ratio) double-float) - (log2 number 1d0)) + (log2 number)) #+double-double (((foreach single-float double-float) double-double-float) diff --git a/tests/irrat.lisp b/tests/irrat.lisp index a6a405d..14db13e 100644 --- a/tests/irrat.lisp +++ b/tests/irrat.lisp @@ -37,6 +37,22 @@ (assert-true (typep result true-type) result true-type))))) +(define-test log2.special-cases + (let* ((y (log 3/2 2)) + (e (relerr y 0.5849625007211562d0))) + (assert-true (<= e + 2.308d-8) + e y)) + (let* ((y (log -3/2 2)) + (ry (realpart y)) + (iy (imagpart y)) + (er (relerr ry 0.5849625007211562d0)) + (ei (relerr iy (/ pi (log 2d0))))) + (assert-true (<= er 2.308d-8) + er ry) + (assert-true (<= ei 1.433d-8) + ei iy))) + ;; This tests that log base 10 returns the correct value and the ;; correct type. (define-test log10.result-types @@ -129,3 +145,10 @@ do (assert-true (<= e threshold) k e x y)))) + +(define-test log2.relationships + (loop for k from 1 below 1000 + for x = (expt 1.1w0 k) + for logx = (kernel::dd-%log2 x) + for log1/x = (kernel::dd-%log2 (/ x)) + do (assert-true (<= (abs (+ logx log1/x)) (* 1 double-float-epsilon))))) ----------------------------------------------------------------------- Summary of changes: src/code/irrat.lisp | 11 +++++++---- tests/irrat.lisp | 23 +++++++++++++++++++++++ 2 files changed, 30 insertions(+), 4 deletions(-) hooks/post-receive -- CMU Common Lisp