[Jprogramming] verb that reads from mathematical notation?

[Roger Hui]

A problem with "paper math" is that the rules are ambiguous.  For example,
in ab+ba do you interpret ab as the name ab or as a times b?

See Ken Iverson's *Conventions Governing Order of
Evaluation<http://www.jsoftware.com/papers/EvalOrder.htm>
 *from 1966.


On Thu, Aug 1, 2013 at 9:40 AM, EelVex <eelvex at gmail.com> wrote:

> Hi bob,
> that's the problem (I think I was not clear): I want to read the output
> from another program that makes symbolic calculations and I don't want to
> have to read huge expressions just to parenthesise them correctly.
>
>
> On Thu, Aug 1, 2013 at 7:31 PM, bob therriault <bobtherriault at mac.com
> >wrote:
>
> > Hi Eelvex,
> >
> > I think that the monadic primitive Do (".) may be the answer, although
> you
> > would need to use parenthesis to get the order of execution that you
> would
> > like.
> >
> >    a=.2
> >    b=.3
> >    ".'a*b+b*a'
> > 18
> >    ".'(a*b)+b*a'
> > 12
> >
> > Cheers, bob
> >
> > On 2013-08-01, at 9:22 AM, EelVex wrote:
> >
> > > Is there a verb in the library to read "paper math" into J expressions?
> > >
> > > Eg.
> > >   a =: 2
> > >   b =: 3
> > >   read 'a * b + b * a'
> > > 12
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