Bug 1147703

Summary:	floating point under/overflows prevent unit conversion
Product:	[Fedora] Fedora	Reporter:	Przemek Klosowski <przemek>
Component:	units	Assignee:	Kamil Dudka <kdudka>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	20	CC:	kdudka, lnie, przemek
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	units-2.11-4.fc21	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-10-22 08:53:48 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Przemek Klosowski 2014-09-29 22:16:38 UTC

Description of problem: relatively simple units result in 
Unit reduction error (bad unit definition)

Version-Release number of selected component (if applicable):
units-2.02-3.fc20.x86_64


How reproducible: Every time


Steps to Reproduce:
1. run units on the commandline
2. type input :  
sigma^3


Actual results: error message:
Unit reduction error (bad unit definition)

Expected results: no error


Additional info:
This probably results from underflow in floating point calculations. sigma is defined as pi^2 k^4 / 60 hbar^3 c^2 and even small powers result in unfortunate under/overflows.

Comment 1 Kamil Dudka 2014-10-08 14:52:45 UTC

Sorry for the delay, I have been on vacation.  The error no longer occurs with units-2.11-3.fc22.  Is the following a correct response?

$ units
Currency exchange rates from www.timegenie.com on 2014-04-02 
2866 units, 109 prefixes, 79 nonlinear units

You have: sigma^3
You want: 
        Definition: 1.8232019e-22 kg^3 / K^12 s^9

Comment 2 Przemek Klosowski 2014-10-08 17:07:52 UTC

I believe that is correct.

Comment 3 Kamil Dudka 2014-10-08 17:30:56 UTC

Thanks for the confirmation!  I will submit an update of units for Fedora 20.

Comment 4 Kamil Dudka 2014-10-10 12:12:23 UTC

AFAIK, the upstream of units provides no SCM repository to pick the fix from, and there were too many changes between units-2.02 and units-2.11 (fixes, enhancements, indentation changes, ...):

$ diff -up ./units-2.02/units.c ./units-2.11/units.c | diffstat
 units.c | 3639 ++++++++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 2415 insertions(+), 1224 deletions(-)

So I will just rebase units in Fedora 20 to the version we have in Fedora 21...

Comment 5 Fedora Update System 2014-10-10 13:11:50 UTC

units-2.11-1.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/units-2.11-1.fc20

Comment 6 Fedora Update System 2014-10-11 06:57:07 UTC

Package units-2.11-1.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing units-2.11-1.fc20'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2014-12629/units-2.11-1.fc20
then log in and leave karma (feedback).

Comment 7 Fedora Update System 2014-10-13 10:16:05 UTC

units-2.11-2.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/units-2.11-2.fc20

Comment 8 Fedora Update System 2014-10-13 10:16:12 UTC

units-2.11-4.fc21 has been submitted as an update for Fedora 21.
https://admin.fedoraproject.org/updates/units-2.11-4.fc21

Comment 9 lnie 2014-10-14 02:59:14 UTC

units-2.11-2.fc20 works

Comment 10 Fedora Update System 2014-10-22 08:53:48 UTC

units-2.11-2.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.

Comment 11 Fedora Update System 2014-11-10 06:20:46 UTC

units-2.11-4.fc21 has been pushed to the Fedora 21 stable repository.  If problems still persist, please make note of it in this bug report.