[om] Representing Nested Summation in OpenMath

[Professor James Davenport]

On Mon, 11 Nov 2002, Muthukkaruppan ANNAMALAI wrote:

> Hello there,
> 
>       Can the existing constructors/ operatiors represent summation
> involving vector P as described by the following  expression?
> 
>    \[  \sum_{i=0}^n   \sum_{j=0}^n {\frac {P_i} {P_j} }  \]
> 
I don't see why not: it would look something like
<OMOBJ>
  <OMA>
    <OMS cd="arith1" name="sum"/>
      <OMA>
        <OMS cd="interval1" name="integer_interval"/>
        <OMI> 0 </OMI>
        <OMV name="n"/>
      </OMA>
      <OMBIND>
        <OMS cd="fns1" name="lambda"/>
          <OMBVAR>
            <OMV name="i"/>
          </OMBVAR>
          <OMA>
            <OMS cd="arith1" name="sum"/>
              <OMA>
                <OMS cd="interval1" name="integer_interval"/>
                <OMI> 0 </OMI>
                <OMV name="n"/>   
              </OMA>
              <OMBIND>
                <OMS cd="fns1" name="lambda"/>
                  <OMBVAR>
                    <OMV name="j"/>
                  </OMBVAR>
                  <OMA>
                    <OMS name="divide" cd="arith1"/>
                    <OMA>
                      <OMS name="list_selector" cd="list2"/>
                      <OMV name="P"/>
                      <OMV name="i"/>
                    </OMA>
                    <OMA>
                      <OMS name="list_selector" cd="list2"/>
                      <OMV name="P"/>
                      <OMV name="j"/>
                    </OMA>
                  </OMA>
              </OMBIND> 
          </OMA>
      </OMBIND>
  </OMA>
</OMOBJ>

The only point is that I have used list_selector from the contributed 
list2, because there isn't really any way except treating P as a function 
to say P_i. 

James Davenport  
--
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