MATLAB Central Newsreader - Extended Symbolic Toolbox, code not working under new versions

Extended Symbolic Toolbox, code not working under new versions

Dingyu Xue — Mon, 07 Apr 2008 10:17:01 -0400

The following codes used to run in earlier versions, but now
it is not working under 2007b, 2008a

maple('with(numtheory):'); f=maple(['cfe:=cfrac(pi,20)'])
n=maple('nthnumer','cfe',4); d=maple('nthdenom','cfe',4)

Re: Extended Symbolic Toolbox, code not working under new versions

Steven Lord — Mon, 07 Apr 2008 16:44:10 -0400

"Dingyu Xue" <xuedingyu@mail.neu.edu.cn> wrote in message
news:ftcsat$gtm$1@fred.mathworks.com...
> The following codes used to run in earlier versions, but now
> it is not working under 2007b, 2008a
>
> maple('with(numtheory):'); f=maple(['cfe:=cfrac(pi,20)'])
> n=maple('nthnumer','cfe',4); d=maple('nthdenom','cfe',4)

I haven't investigated to determine what changed, but if you're trying to
work with the continued fraction for the constant pi, and not the number
theory function pi(n), try replacing 'pi' in your MAPLE call that creates f
with 'Pi'.

--
Steve Lord
slord@mathworks.com

Re: Extended Symbolic Toolbox, code not working under new versions

Ben Hinkle — Mon, 07 Apr 2008 17:22:30 -0400

"Steven Lord" <slord@mathworks.com> wrote in message
news:ftdj0r$4p5$1@fred.mathworks.com...
>
> "Dingyu Xue" <xuedingyu@mail.neu.edu.cn> wrote in message
> news:ftcsat$gtm$1@fred.mathworks.com...
>> The following codes used to run in earlier versions, but now
>> it is not working under 2007b, 2008a
>>
>> maple('with(numtheory):'); f=maple(['cfe:=cfrac(pi,20)'])
>> n=maple('nthnumer','cfe',4); d=maple('nthdenom','cfe',4)
>
> I haven't investigated to determine what changed, but if you're trying to
> work with the continued fraction for the constant pi, and not the number
> theory function pi(n), try replacing 'pi' in your MAPLE call that creates
> f with 'Pi'.

Maple changes the way in which aliases are used between Maple 8 (which was
the Maple version used prior to R2007b) and Maple 10. After executing
'with(numtheory)' the name 'pi' no longer is aliased to Pi as is usually the
case with the Symbolic Math Toolbox. Instead pi means numtheory:-pi. An
alternative to Steve's solution is to not import numtheory and instead write
out numtheory:-cfrac, numtheory:-nthnumer and numtheory:-nthdenom.

Hope that help,
-Ben

Re: Extended Symbolic Toolbox, code not working under new versions

Dingyu Xue — Mon, 07 Apr 2008 23:23:03 -0400

"Ben Hinkle" <bhinkle@mathworks.com> wrote in message
<ftdl8l$htc$1@fred.mathworks.com>...
> "Steven Lord" <slord@mathworks.com> wrote in message
> news:ftdj0r$4p5$1@fred.mathworks.com...
> >
> > "Dingyu Xue" <xuedingyu@mail.neu.edu.cn> wrote in message
> > news:ftcsat$gtm$1@fred.mathworks.com...
> >> The following codes used to run in earlier versions,
but now
> >> it is not working under 2007b, 2008a
> >>
> >> maple('with(numtheory):'); f=maple(['cfe:=cfrac(pi,20)'])
> >> n=maple('nthnumer','cfe',4); d=maple('nthdenom','cfe',4)
> >
> > I haven't investigated to determine what changed, but if
you're trying to
> > work with the continued fraction for the constant pi,
and not the number
> > theory function pi(n), try replacing 'pi' in your MAPLE
call that creates
> > f with 'Pi'.
>
> Maple changes the way in which aliases are used between
Maple 8 (which was
> the Maple version used prior to R2007b) and Maple 10.
After executing
> 'with(numtheory)' the name 'pi' no longer is aliased to Pi
as is usually the
> case with the Symbolic Math Toolbox. Instead pi means
numtheory:-pi. An
> alternative to Steve's solution is to not import numtheory
and instead write
> out numtheory:-cfrac, numtheory:-nthnumer and
numtheory:-nthdenom.
>
> Hope that help,
> -Ben
>
>
Thanks Ben, I found this by accident last night. So why the
change? It may confuse many Matlab users