How do you encode "a < b = c" in content MathML?

[J.Fine]

Perhaps you'll tell me to read the manual, but I wondered: How do you encode
   A = b = c
   a < b < c
   a < b = c
etc in content MathML?

In fact, I had a look at the manual and the closest I could find is
    http://www.w3.org/TR/2009/WD-MathML3-20090924/chapter4.html#contm.nary.reln



Jonathan


The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302).

[mozer]

Probably with TWO assertions
Something like
>   A = b = c
A = b
b = c
>   a < b < c
a < b
b < c
>   a < b = c
a < b
b = c


On Mon, Nov 2, 2009 at 10:30 AM, J.Fine <J.Fine@...> wrote:

> Perhaps you'll tell me to read the manual, but I wondered: How do you encode
>   A = b = c
>   a < b < c
>   a < b = c
> etc in content MathML?
>
> In fact, I had a look at the manual and the closest I could find is
>    http://www.w3.org/TR/2009/WD-MathML3-20090924/chapter4.html#contm.nary.reln
>
>
>
> Jonathan
>
>
> The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302).
>
>

[J.Fine]

Well, with Python I don't have to do that
---
$ python
Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
[GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 1 < 2 <= 3
True
>>>
---

It is common for mathematicians to write
    A < B = C < D
for complicated expressions A, B, C, D.

So this seems to be something lacking in MathML (and present in Python).


Jonathan

> -----Original Message-----
> From: mozer [mailto:xmlizer@...]
> Sent: 02 November 2009 09:42
> To: J.Fine
> Cc: www-math@...
> Subject: Re: How do you encode "a < b = c" in content MathML?
>
> Probably with TWO assertions
> Something like
> >   A = b = c
> A = b
> b = c
> >   a < b < c
> a < b
> b < c
> >   a < b = c
> a < b
> b = c
>
>
> On Mon, Nov 2, 2009 at 10:30 AM, J.Fine <J.Fine@...> wrote:
> > Perhaps you'll tell me to read the manual, but I wondered: How do you
> encode
> >   A = b = c
> >   a < b < c
> >   a < b = c
> > etc in content MathML?
> >
> > In fact, I had a look at the manual and the closest I could find is
> >    http://www.w3.org/TR/2009/WD-MathML3-
> 20090924/chapter4.html#contm.nary.reln
> >
> >
> >
> > Jonathan
> >
> >
> > The Open University is incorporated by Royal Charter (RC 000391), an
> exempt charity in England & Wales and a charity registered in Scotland (SC
> 038302).
> >
> >

The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302).

[Robert Miner]

Hi.

 

To actually mix the relational operator in such a chain of inequalities, one must for a conjunction, e.g. A<B and B=C and C<D. 

 

It is true that content MathML does not provide syntactic sugar for many idiomatic notations.  The view point of content MathML 3 is more oriented toward being explicit about semantics.

 

--Robert

---

From: www-math-request@... on behalf of J.Fine
Sent: Mon 11/2/2009 4:21 AM
To: 'mozer'
Cc: 'www-math@...'
Subject: RE: How do you encode "a < b = c" in content MathML?

Well, with Python I don't have to do that
---
$ python
Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
[GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 1 < 2 <= 3
True
>>>
---

It is common for mathematicians to write
    A < B = C < D
for complicated expressions A, B, C, D.

So this seems to be something lacking in MathML (and present in Python).


Jonathan

> -----Original Message-----
> From: mozer [xmlizer@...]
> Sent: 02 November 2009 09:42
> To: J.Fine
> Cc: www-math@...
> Subject: Re: How do you encode "a < b = c" in content MathML?
>
> Probably with TWO assertions
> Something like
> >   A = b = c
> A = b
> b = c
> >   a < b < c
> a < b
> b < c
> >   a < b = c
> a < b
> b = c
>
>
> On Mon, Nov 2, 2009 at 10:30 AM, J.Fine <J.Fine@...> wrote:
> > Perhaps you'll tell me to read the manual, but I wondered: How do you
> encode
> >   A = b = c
> >   a < b < c
> >   a < b = c
> > etc in content MathML?
> >
> > In fact, I had a look at the manual and the closest I could find is
> >    http://www.w3.org/TR/2009/WD-MathML3-
> 20090924/chapter4.html#contm.nary.reln
> >
> >
> >
> > Jonathan
> >
> >
> > The Open University is incorporated by Royal Charter (RC 000391), an
> exempt charity in England & Wales and a charity registered in Scotland (SC
> 038302).
> >
> >

The Open University is incorporated by Royal Charter (RC 000391), an exempt charity in England & Wales and a charity registered in Scotland (SC 038302).

[William F Hammond]

Robert Miner writes in reply to Jonathan Fine:

> > It is common for mathematicians to write
> >     A < B = C < D
> > for complicated expressions A, B, C, D.
> > Well, with Python I don't have to do that
> > ---
> > $ python
> > Python 2.5.2 (r252:60911, Dec  2 2008, 09:26:14)
> > [GCC 3.4.4 (cygming special, gdc 0.12, using dmd 0.125)] on cygwin
> > Type "help", "copyright", "credits" or "license" for more information.
> > >>> 1 < 2 <= 3
> > True

So also this works in sage (www.sagemath.org) -- the free computer
algebra system project headed by William Stein with more than 125
contributers -- that uses python as its executive language.

> The view point of content MathML 3 is more oriented toward being
> explicit about semantics.

Long term (for the spec following MathML 3) I would hope that, given
the rather elaborate typing in sage (www.sagemath.org), anything
sufficiently explicit for sage should be sufficiently explicit for
content mathml.

                                    -- Bill

[polx]

Do you mean in Content-MathML?
(in presentation MathML it is trivial).
This is a known limitation for both OpenMath and MathML and has been  
such since everyone tells you that this is semantically equivalent to  
A<B and B=C and C<D.
I guess this is exactly what we should use to introduce such "chained  
operators symbol" but no-one has done it yet.

paul




Le 02-nov.-09 à 11:21, J.Fine a écrit :

> It is common for mathematicians to write
>    A < B = C < D
> for complicated expressions A, B, C, D.
>
> So this seems to be something lacking in MathML (and present in  
> Python).