This site is a static rendering of the Trac instance that was used by R7RS-WG1 for its work on R7RS-small (PDF), which was ratified in 2013. For more information, see Home.
Source for ticket #469
cc
changetime
2012-10-12 06:24:02
component
WG1 - Core
description
{{{
On Wed, Aug 8, 2012 at 5:11 AM, Mark H Weaver <mhw@netris.org> wrote:
>> There is widespread agreement in the relevant floating point standards
>> (C99, C11, ISO/IEC 10967, and probably IEEE 754 although I haven't
>> purchased a copy) that (angle -0.0-0.0i) = (atan -0.0 -0.0) = -pi, but
>> the definition of 'angle' on page 36 of R7RS-draft-6 (section 6.2.6)
>> asserts that -pi< (angle z)<= pi for all complex 'z'. I suggest that
>> this be changed to -pi<= (angle z)<= pi.
>
> Another problem along the same lines: earlier on page 36, R7RS-draft-6
> asserts that the value of "log z is defined to be the one whose
> imaginary part lies in the range from -pi (exclusive) to pi
> (inclusive)", and then proceeds to define the inverse trigonometric
> functions in terms of log. That should be changed to '-pi (inclusive)'.
>
> Note that X3J13 voted for these changes to Common Lisp in January 1989.
> Search for "COMPLEX-ATAN-BRANCH-CUT" in the following pages for more
> details:
}}}
http://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node128.html
http://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node129.html
id
469
keywords
milestone
owner
cowan
priority
major
reporter
cowan
resolution
fixed
severity
status
closed
summary
Change definition of (atan -0.0 -0.0)
time
2012-08-29 12:10:17
type
defect
Changes
Change at time 2012-10-12 06:24:02
author
cowan
field
comment
newvalue
oldvalue
4
raw-time
1349997842512012
ticket
469
time
2012-10-12 06:24:02
Change at time 2012-10-12 06:24:02
author
cowan
field
resolution
newvalue
fixed
oldvalue
raw-time
1349997842512012
ticket
469
time
2012-10-12 06:24:02
Change at time 2012-10-12 06:24:02
author
cowan
field
status
newvalue
closed
oldvalue
writing
raw-time
1349997842512012
ticket
469
time
2012-10-12 06:24:02
Change at time 2012-09-19 00:33:29
author
cowan
field
comment
newvalue
The first point has been added. The second point was already added as an editorial change.
oldvalue
3
raw-time
1347989609064731
ticket
469
time
2012-09-19 00:33:29
Change at time 2012-09-19 00:33:29
author
cowan
field
owner
newvalue
cowan
oldvalue
alexshinn
raw-time
1347989609064731
ticket
469
time
2012-09-19 00:33:29
Change at time 2012-09-19 00:33:29
author
cowan
field
status
newvalue
writing
oldvalue
decided
raw-time
1347989609064731
ticket
469
time
2012-09-19 00:33:29
Change at time 2012-09-19 00:20:46
author
cowan
field
comment
newvalue
WG1 accepted this under no-objection procedure.
oldvalue
2
raw-time
1347988846291581
ticket
469
time
2012-09-19 00:20:46
Change at time 2012-09-19 00:20:46
author
cowan
field
status
newvalue
decided
oldvalue
new
raw-time
1347988846291581
ticket
469
time
2012-09-19 00:20:46
Change at time 2012-08-29 12:11:46
author
cowan
field
comment
newvalue
See also http://www.lispworks.com/documentation/lw61/CLHS/Issues/iss069_w.htm and http://www.lispworks.com/documentation/lw61/CLHS/Issues/iss192_w.htm.
oldvalue
1
raw-time
1346217106438264
ticket
469
time
2012-08-29 12:11:46