[om] Re: prefix in units_ops1

[Professor James Davenport]

On Wed, 24 Sep 2003, Bill Naylor wrote:
> 
> I am unhappy with the definition of the prefix symbol in units_ops1:
> 
> "prefix
> 
> This symbol represents the fact that the subsequent unit has been
> effectively multiplied by 1,000 ($10^{3}$) "
> 
> This seems to me to be a particular application of prefix, viz. to the
> kilo symbol. I think something much more along the lines of:
> 
> This symbol represents the fact that the second argument (a unit) has been
> effectively multiplied by a constant specified by the first argument (a
> prefix).
> 
You are absolutely right. For some reason, the Example got pasted into 
the description. Will fix.
James> 
-------------- next part --------------
<CD>
<CDName> units_ops1 </CDName>
<CDURL> http://www.openmath.org/cd/units_ops1.ocd </CDURL>
<CDReviewDate> 2004-04-01 </CDReviewDate>
<CDStatus> experimental </CDStatus>
<CDDate> 2003-08-21 </CDDate>
<CDVersion> 1 </CDVersion>
<CDRevision> 0 </CDRevision>
<CDUses>
  <CDName>arith1</CDName>
  <CDName>relations1</CDName>
  <CDName>units_siprefix1</CDName>
</CDUses>

<Description> 
This CD defines various symbols for use in the manipulation of units.
</Description>

<CDDefinition>
<Name> prefix </Name>
<Description>
This symbol represents the fact that the subsequent unit has been 
effectively multiplied by 1,000 ($10^{3}$ in the case of kilo) , or whatever
value the prefix might indicate.
</Description>
<CMP> This is unit multiplication by the value of the prefix</CMP>

<Example>
Prefixing with 'kilo' means that the unit has been
effectively multiplied by 1,000 ($10^{3}$)
<OMOBJ>
<OMA>
  <OMS name="eq" cd="relations1"/>
  <OMA>
    <OMS name="times" cd="arith1"/>
    <OMI> 1 </OMI>
    <OMA>
      <OMS name="prefix" cd="units_ops1"/>
      <OMS name="kilo" cd="units_siprefix1"/>
      <OMV name="unit"/>
    </OMA>
  </OMA>
  <OMA>
    <OMS name="times" cd="arith1"/>
    <OMA>
      <OMS name="power" cd="arith1"/>
      <OMI> 10 </OMI>
      <OMI> 3 </OMI>
    </OMA>
    <OMV name="unit"/>
  </OMA>
</OMA>
</OMOBJ></Example>

</CDDefinition>

</CD>