[Haskell-cafe] Re: iterative algorithms: how to do it in Haskell?

Gene A yumagene at gmail.com
Sat Aug 19 11:51:53 EDT 2006

Hi Lennart,

  This morning when I posted..it was about 2:30am and had been up a
long time... bad habits.. I sent a message to Henk-Jan to that effect,
but didn't send to the entire list.. anyway thanks to both for the
followups... I still tend to sometimes do things the hard way in
Haskell.  Started trying to learn it starting in I think Nov-Dec. of
2005, so not too awfully long, but with a lot of other things soaking
up time, not as far along as I wished to be in even this amount of
time... Most interesting language I have used yet.

 but yes not sure why not the precision.. but I think when I tried
that with the way I had the thing in the original, I used  (**) 1/3
and got an error message which I was too tired to even read,..and just
changed it to 0.33333333 or whatever .... however many 3's , and just
got it posted.. I don't think that those functions are of much use,
the thing was that when I wrote them, not at 2AM in the morning, I
remember thinking just how easy it was to do pretty much anything you
want with this language.. Off topic, but one of my tests of a
language, old habit this, is as soon as I know enough to be dangerous,
I try writing a forth interpreter in it.  I have started such a thing,
a module I call Hforth, and it is operational, but do to the nature of
lists not holding homogeneos values in Haskell everything has to be
stored with String values.  This has the result of having to apply
show function to store numerics to the stack and then to use the read
function to convert back when popping the stack.. .. hmm still
tired... Anyway the upshot is that a very rudimentary interpreter is
up and running to do simple things with just builtins so far, but was
built in a matter of some fairly small number of hours.  Doesn't
support line editing yet, so really not too good, but does support
pushing strings and concatenation and some other things that are more
tedious to write as primatives in other languages..  The only other
language that was as easy to get to this stage with was scheme.

Sorry for the ramble,

On 8/19/06, Lennart Augustsson <lennart at augustsson.net> wrote:
> On Aug 19, 2006, at 05:14 , Henk-Jan van Tuyl wrote:
> >
> > [...]
> >> *Iteration> fromtoby 12 42 3  (flip (**) 0.3333333333)
> >
> > fromtoby 12 42 3  (**0.3333333333)
> >
> And why approximate so much?
> fromtoby 12 42 3 (** (1/3))

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