a .. b



In that case, really, how hard would it be to have 3..1/2..4  come out as
the sequence [3,7/2,4]?
The parser should produce ((matseq) 3 ((matseq) 1/2 4))  which should first
be simplified to  something like

((matseq) 3 1/2 4)

which should then be evaluated as makelist(3+ 1/2*i,i,0, (4-3)+1).

in general, makelist(a+increment*index,index,0, (high-low)+1)    or
something like that.

makelist however craps out when the list cannot really be expanded
explicitly,
so maybe we need an implicit makelist  (noun, delayed evaluation ,
whatever)/



 

> -----Original Message-----
> From: Barton Willis [mailto:willisb at unk.edu] 
> Sent: Friday, June 20, 2008 9:14 AM
> To: fateman at EECS.Berkeley.EDU
> Cc: 'Robert Dodier'; 'Maxima List'
> Subject: Re: [Maxima] a .. b
> 
> -----maxima-bounces at math.utexas.edu wrote: -----
> 
> 
> >I think that consistency with Macsyma means consistency with 
> a design that
> >has perhaps has had more professional thought than we may be 
> willing to
> >commit to at the moment. It is not just a matter of portability of
> >programs.
> 
> There is more---dot-dot was introduced to Macsyma for matlab
> support. So compatibility with Macsyma also means compatibility with
> the matlab language(s).
> 
> Now I see that Macsyma allows a user-supplied step (as suggested by
> Raymond).  but I think doing this would require a change to the parser
> (or make dot-dot a prefix operator---making dot-dot no faster to type
> than makelist).
> 
> Barton
> 
>