Bug 34617

Summary:	/usr/bin/units mangles temperature conversion
Product:	Base System	Reporter:	Ed Symanzik <zik>
Component:	misc	Assignee:	freebsd-bugs (Nobody) <bugs>
Status:	Closed FIXED
Severity:	Affects Only Me
Priority:	Normal
Version:	Unspecified
Hardware:	Any
OS:	Any

Description Ed Symanzik 2002-02-04 19:50:01 UTC

units results for temperature conversions is incorrect. 
units will not accept non-positive numbers.

The problem is that temperature scales do not intersect
at zero.  There should be a way to note this in units.lib.

Perhaps
  degC  K +273
  degF  5|9 degC +32

How-To-Repeat: > units
497 units, 54 prefixes
You have: 20 degC
You want: K
	* 20
	/ 0.05
You have: 32 degF
You want: degC
	* 17.777778
	/ 0.05625
You have: 0 degF
units: unit reduces to zero
You have: -9 degC
unknown unit '-'

Comment 1 greid freebsd_committer

2002-02-04 22:49:30 UTC

State Changed
From-To: open->closed

This is expected behaviour.  From units(1): 

The units program converts quantities expressed in various scales to 
their equivalents in other scales.  The units program can only handle 
multiplicative scale changes.  It cannot convert Celsius to Fahrenheit, 
for example.

Comment 2 Ed Symanzik 2002-02-05 13:14:58 UTC

I looked right over that.  I was expecting a notice like
that to appear in the Bugs section.