Long identifiers allowed? Linking data to MathML identifiers?

Hi Folks,

I am just learning MathML, so please bear with me if my questions are
naive.  I have two questions.

1. Can MathML identifiers be of more that one character?  For example,
suppose that I wanted to express this formula in MathML:

    kilometers = miles * 1.62

I can imagine two ways to express this (using content markup).

a. Use the full names as identifiers:

    <math>
        <apply>
            <eq/>
            <ci>kilometers</ci>
            <apply>
                <times/>
                <ci>miles</ci>
                <cn>1.62</cn>
            </apply>
        </apply>
    </math>

b. Use the full names as the value of id attributes:

    <math>
        <apply>
            <eq/>
            <ci id="kilometers">k</ci>
            <apply>
                <times/>
                <ci id="miles">m</ci>
                <cn>1.62</cn>
            </apply>
        </apply>
    </math>

- Are both of these acceptable?
- If so, is one form preferred over another?

2. MathML identifiers (ci) are essentially variables.  To evaluate a
MathML formula requires that the variables (identifiers) be replaced
with actual values.  Suppose that there exists a separate XML document
which contains the values that you want plugged in for the variables. 
For example:

    <River id="Yangtze">
        <length units="miles">3914</length>
    </River>

Suppose that I would like to plug in "3914" for "miles" in the above
MathML.  Is there a recommended practice for linking "3914" to the
MathML "miles" identifier?  

/Roger

Received on Sunday, 13 July 2003 09:51:43 UTC