Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.soft-sys.math.maple > #292

Re: A hypergeom evaluation

From Axel Vogt <&noreply@axelvogt.de>
Newsgroups comp.soft-sys.math.maple
Subject Re: A hypergeom evaluation
Date 2012-01-06 14:47 +0100
Message-ID <9moccvF155U1@mid.individual.net> (permalink)
References (5 earlier) <413bc08a-2d0e-4f36-97d4-b65e1dfa9bea@ck5g2000vbb.googlegroups.com> <9mm9ciFv2jU1@mid.individual.net> <d5ece933-5220-4f79-af88-6c06cb23fa00@u6g2000vbc.googlegroups.com> <9mo18dFac0U1@mid.individual.net> <f0a5e29f-a06f-4c3c-93bb-71fc744a0c28@l24g2000yqm.googlegroups.com>

Show all headers | View raw


On 06.01.2012 12:51, Peter Luschny wrote:
> Axel, I agree with most of what you said.
...
> The question here is: What is the reason that Maple V choose (2) over
> (3)? Is this justified? The problem as stated -- H(n,m,x) -- does not
> indicate that one parameter is to preferred over the other.
....

I do not know, but these are different ways

(3*) limit(hypergeom([1/2, 1-n, 1],[1, 2-2*n],2),n = 1);
      evalf[10](%);

Even if I do not know, what Maple does in evalf/limit to accelerate
it will certainly evaluate n close (but not identical) to 1, which
is ~ 0.5 + 0.5*I, thus the answer.

(2*) hypergeom([m-n, 1/2*m, 1/2+1/2*m],[m, 1+m-2*n],x)
      eval(%, n=1);
      simplify(%);subs(x=2,%);
      eval(%, m=1);

through the 2nd command 'cancels' identical terms in the first and
the second parameter list, a kind of 'lifting away the problem',
the simplify converts it to a square root.




Back to comp.soft-sys.math.maple | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-04 09:22 -0800
  Re: A hypergeom evaluation Joe Riel <joer@san.rr.com> - 2012-01-04 10:42 -0800
    Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-04 19:59 +0100
    Re: A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-04 11:08 -0800
      Re: A hypergeom evaluation "G. A. Edgar" <edgar@math.ohio-state.edu.invalid> - 2012-01-05 06:21 -0700
        Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-05 14:47 +0100
          Re: A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-05 10:01 -0800
            Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-05 19:44 +0100
              Re: A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-05 11:57 -0800
                Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-06 11:37 +0100
                Re: A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-06 03:51 -0800
                Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-06 14:47 +0100
                Re: A hypergeom evaluation "G. A. Edgar" <edgar@math.ohio-state.edu.invalid> - 2012-01-07 06:10 -0700
            Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-05 20:05 +0100
              Re: A hypergeom evaluation Peter Luschny <peter.luschny@googlemail.com> - 2012-01-05 12:17 -0800
                Re: A hypergeom evaluation Axel Vogt <&noreply@axelvogt.de> - 2012-01-05 23:02 +0100

csiph-web