Precision and CD's

David Carlisle davidc at
Fri Jul 16 12:04:39 CEST 1999

> Are you suggesting the mantissa OMI should be required to be in the same
> base as the radix?  

The OM Object for integers does not have a concept of the base in which
the integer was entered (the x10 / 16 distinction is just a feature of
the xml encoding) so this requirement wouldn't really be possible to
enforce even if you wanted it.

>  (I hope you aren't proposing that the bigfloat should be
> presented that way by a formatter!)

I think it is just an ad hoc encoding just to avoid writing out the xml
encoding, plus(1,2,3) or even (plus 1 2 3) being somewhat easier to type
than the XML encoding of same.

> Anyway, John Davenport's bigfloat CD has a lot going for it, but I'm
> still wondering what a formatter, or converter to MathML, would
> do with this type of bigfloat.

One of the list of jobs to do is to provide, for each of the core CDs,
translations to presentation MathML (probably expressed in XSL). This
will provide a standard presentation of every openmath object using the
core CDs (individual systems may choose a different presentation of
course). A related activity is to provide, for the CDs in the `MathML
CDGroup' XSL transformations that specify exactly what is the mapping
between OM and Content MathML. Mapping <OMS cd="transc1" name="sin"/> to
<sin/> is fairly obvious but the correspondence for some things,
especially anything involving bound variables, is more involved and so
we ought to really have the transformations explicit. So the final
release of the core openmath CDs (including one for floats, if that's
the way this goes) should include a specification answering the two
questions that you ask above. (So only they still need to be answered,
but only once:-)


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