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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

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1349997842512012

ticket

469

time

2012-10-12 06:24:02

Change at time 2012-10-12 06:24:02

author

cowan

field

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newvalue

fixed

oldvalue


    

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1349997842512012

ticket

469

time

2012-10-12 06:24:02

Change at time 2012-10-12 06:24:02

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cowan

field

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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

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cowan

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cowan

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alexshinn

raw-time

1347989609064731

ticket

469

time

2012-09-19 00:33:29

Change at time 2012-09-19 00:33:29

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cowan

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newvalue

writing

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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