[Om3] [Fwd: Re: OpenMath Symbols for Symbolic Computation]

[jhd at cs.bath.ac.uk]

Whoops: forgot the list.

---------------------------- Original Message ----------------------------
Subject: Re: [Om3] OpenMath Symbols for Symbolic Computation
From:    jhd at cs.bath.ac.uk
Date:    Wed, September 17, 2008 11:45 pm
To:      "Peter Horn" <hornp at mathematik.uni-kassel.de>
Cc:      "Professor James Davenport" <jhd at cs.bath.ac.uk>
--------------------------------------------------------------------------


On Wed, September 17, 2008 12:29 pm, Peter Horn wrote:
> Hi!
>
>> I would disgaree here. A Matrix is precisely that, and needs no
>> additional
>> information. IF you wnat that matrix to represent a linear
>> transformation
>> on a space, THEN you need additional information.
>
> Well, if you want to do computations with a matrix (and that's our
> intention), you need all the information we define in matrix1.
I think I deny that. If (as I believe I can) I can multiply
<OMI>2</OMI> by <OMI>3</OMI>, then surely I can multiply
<OMA>
  <OMS name="matrix" cd="linalg2"/>
  <OMA> <OMS name="matrixrow" cd="linalg2"/> <OMI>2</OMI> </OMA>
</OMA>
by
<OMA>
  <OMS name="matrix" cd="linalg2"/>
  <OMA> <OMS name="matrixrow" cd="linalg2"/> <OMI>3</OMI> </OMA>
</OMA>.
And if I can do that, then why not 2x2 matrices, or other sizes?
>>> Sure. We want to work with matrices (and other objects) in computer
>>> algebra systems, and as you can imagine it's hard to guess (from
>>> the CAS'
>>> POV) what the user is trying to tell us when even the most basic
>>> information is missing.
>> Right - rather like the polyd family. of CDs. Having such a set of CDs
>> certainly makes sense
>
> We simply adopted the polyd ideas to matrices.
>
>> I'd be happy to look at what you have: I have Peter Horn's matrix1,
>> but don't quite see, for instance, what the point of entry_domain is?
>
> That's the ground ring.
But I don't see what it does. What does
<OMA>
  <OMS name="entry_domain" cd="matrix1"/>
  <OMS name="Z" cd="setname1"/>
</OMA>
have that just
<OMS name="Z" cd="setname1"/> (or ringname1 if you want) not have?

> BTW: matrix1 is not mine but it was developed
> by all parties involved in SCIEnce, that is GAP, KANT, MuPAD and
> Maple. We looked to find what we need and defined it accordingly. So
> It's not the work of a bored PhD student but of a group of people that
> want to USE OpenMath for computational purposes. :)
As Paul said: no complaint about the process.

James Davenport
Hebron & Medlock Professor of Information Technology
Formerly RAE Coordinator and Undergraduate Director of Studies, CS Dept
Currently (thankfully briefly) Acting Head, CS Dept
Lecturer on CM30070, 30078, 50209, 50123
Chairman, Powerful Computing WP, University of Bath
OpenMath Content Dictionary Editor
IMU Committee on Electronic Information and Communication





James Davenport
Hebron & Medlock Professor of Information Technology
Formerly RAE Coordinator and Undergraduate Director of Studies, CS Dept
Currently (thankfully briefly) Acting Head, CS Dept
Lecturer on CM30070, 30078, 50209, 50123
Chairman, Powerful Computing WP, University of Bath
OpenMath Content Dictionary Editor
IMU Committee on Electronic Information and Communication