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Source for ticket #370

cc


    

changetime

2012-10-09 00:50:06

component

WG1 - Core

description

R5RS and draft 6 of R7RS don't say what `(log 0.0)` and `(log 0)` return.  R6RS requires `-inf.0` and an exception respectively.  The proposal is to say that `(log 0.0)` returns `-inf.0` on systems that have `+inf.0`, and that `(log 0)` is an error.

In Racket, Gambit, Chicken (with the numbers egg), Guile, Chibi, Chez, !Ikarus/Vicare, Larceny, Ypsilon, Mosh, !IronScheme, STklos, Spark, `(log 0.0)` returns `-inf.0` and `(log 0)` raises an exception.

Gauche, MIT, Chicken (without the numbers egg), Bigloo, Scheme48/scsh, Kawa, SISC, SCM, NexJ, KSi, RScheme, XLisp, Rep, VX, SXM, Inlab return `-inf.0` in both cases.

Elk, UMB, Oaklisp raise an exception in both cases.

Scheme 7 returns the wrong answer in both cases.

!SigScheme, Shoe, !TinyScheme, Dream, BDC, Owl Lisp don't support `log`.

Scheme 9 apparently goes into an infinite loop in both cases.

id

370

keywords


    

milestone


    

owner

cowan

priority

major

reporter

cowan

resolution

fixed

severity


    

status

closed

summary

Log of exact and inexact zero

time

2012-03-29 04:13:29

type

defect

Changes

Change at time 2012-10-09 00:50:06

author

cowan

field

comment

newvalue


    

oldvalue

4

raw-time

1349718606671628

ticket

370

time

2012-10-09 00:50:06

Change at time 2012-10-09 00:50:06

author

cowan

field

resolution

newvalue

fixed

oldvalue


    

raw-time

1349718606671628

ticket

370

time

2012-10-09 00:50:06

Change at time 2012-10-09 00:50:06

author

cowan

field

status

newvalue

closed

oldvalue

writing

raw-time

1349718606671628

ticket

370

time

2012-10-09 00:50:06

Change at time 2012-08-27 09:45:13

author

cowan

field

comment

newvalue


    

oldvalue

3

raw-time

1346035513279400

ticket

370

time

2012-08-27 09:45:13

Change at time 2012-08-27 09:45:13

author

cowan

field

owner

newvalue

cowan

oldvalue

alexshinn

raw-time

1346035513279400

ticket

370

time

2012-08-27 09:45:13

Change at time 2012-08-27 09:45:13

author

cowan

field

status

newvalue

writing

oldvalue

decided

raw-time

1346035513279400

ticket

370

time

2012-08-27 09:45:13

Change at time 2012-08-27 03:03:53

author

cowan

field

comment

newvalue

WG1 voted to adopt this proposal.

oldvalue

2

raw-time

1346011433227990

ticket

370

time

2012-08-27 03:03:53

Change at time 2012-08-27 03:03:53

author

cowan

field

status

newvalue

decided

oldvalue

new

raw-time

1346011433227990

ticket

370

time

2012-08-27 03:03:53

Change at time 2012-03-29 05:11:17

author

cowan

field

comment

newvalue


    

oldvalue

1

raw-time

1332972677068350

ticket

370

time

2012-03-29 05:11:17

Change at time 2012-03-29 05:11:17

author

cowan

field

description

newvalue

R5RS and draft 6 of R7RS don't say what `(log 0.0)` and `(log 0)` return.  R6RS requires `-inf.0` and an exception respectively.  The proposal is to say that `(log 0.0)` returns `-inf.0` on systems that have `+inf.0`, and that `(log 0)` is an error.

In Racket, Gambit, Chicken (with the numbers egg), Guile, Chibi, Chez, !Ikarus/Vicare, Larceny, Ypsilon, Mosh, !IronScheme, STklos, Spark, `(log 0.0)` returns `-inf.0` and `(log 0)` raises an exception.

Gauche, MIT, Chicken (without the numbers egg), Bigloo, Scheme48/scsh, Kawa, SISC, SCM, NexJ, KSi, RScheme, XLisp, Rep, VX, SXM, Inlab return `-inf.0` in both cases.

Elk, UMB, Oaklisp raise an exception in both cases.

Scheme 7 returns the wrong answer in both cases.

!SigScheme, Shoe, !TinyScheme, Dream, BDC, Owl Lisp don't support `log`.

Scheme 9 apparently goes into an infinite loop in both cases.

oldvalue

R5RS and draft 6 of R7RS don't say what `(log 0.0)` and `(log 0)` return.  R6RS requires `-inf.0` and an exception respectively.  The proposal is to say that `(log 0.0)` returns `-inf.0` on systems that have `+inf.0`, and that `(log 0)` is an error.

In Racket, Gambit, Chicken (with the numbers egg), Guile, Chibi, Chez, !Ikarus/Vicare, Larceny, Ypsilon, Mosh, !IronScheme, STklos, Spark, `(log 0.0)` returns `-inf.0` and `(log 0)` raises an exception.

Gauche, Chicken (without the numbers egg), Bigloo, Scheme48/scsh, Kawa, SISC, SCM, NexJ, KSi, RScheme, XLisp, Rep, VX, SXM, Inlab return `+inf.0` in both cases.

Elk, UMB, Oaklisp raise an exception in both cases.

Scheme 7 returns the wrong answer in both cases.

!SigScheme, Shoe, !TinyScheme, Dream, BDC, Owl Lisp don't support `log`.

Scheme 9 apparently goes into an infinite loop in both cases.

I don't know how to shut off floating-point traps in MIT.

raw-time

1332972677068350

ticket

370

time

2012-03-29 05:11:17