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[UDUNITS #TOB-790521]: exponential

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  • Subject: [UDUNITS #TOB-790521]: exponential
  • Date: Thu, 28 Feb 2013 09:54:41 -0700
Pelley,

> I appreciate that there is a logarithm unit, however, if I was to inverse 
> this for example, (i.e. take the exponential of it), then udunits cannot 
> currently handle this:
> 
> Example of what we would expect:
> e^(log('meters')) -> 'meters'

A dimensional exponent (as opposed to a dimensionless one) is a red flag: it 
indicates the use of a numeral-value equation or formula rather than a more 
proper quantity equation or formula. Dimensional analysis teaches us that all 
quantities that appear as exponents or that have their logarithm taken should 
be dimensionless. This is why the logarithmic units in the UDUNITS-2 package 
are dimensionless. For further information see section 7.11 of 
<http://physics.nist.gov/Pubs/SP811/sec07.html> and 
<http://en.wikipedia.org/wiki/Dimensional_analysis>.

Can you provide me with an example of a quantity equation or formula in which 
an exponential unit makes sense?

> Thank you.
> 
> Best Regards,
> 
> Carwyn Pelley
> 
> AVD Software Developer
> 01392 88(5225)

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: TOB-790521
Department: Support UDUNITS
Priority: Normal
Status: Closed