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Re: Function defined by a while loop

From Hans-Bernhard Bröker <HBBroeker@t-online.de>
Newsgroups comp.graphics.apps.gnuplot
Subject Re: Function defined by a while loop
Date Mon, 27 Jun 2011 22:00:24 +0200
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On 27.06.2011 11:50, Antonio Lo Turco wrote:

> Obviously I tried and it doesn't work!

Of course it doesn't.  while is a _command_, not an expression.  You 
can't use it in the middle of an expression, like the one you use to 
define a function.

> However I would like (and I'm not able) to implement such solution as
> a user defined function.

The only way there is recursion.  But that will only work reasonably 
well for a _one_parameter_ loop.  You loop over 'x' and 'i' 
simultaneously.  That doesn't map cleanly to recursion over a single 
variable.

Well, unless you make them the real and imaginary part of a complex 
number that is:

iterate_f(x_i, x0, eps, maxiter) = \
     ((abs(real(x_i) - x0) < eps) || (imag(x_i) > maxiter)) \
     ? x_i \
     : iterate(f(real(x_i)) + (imag(x_i)+1)*{0,1}, x0, eps, maxiter)

print iterate(x0,x0,eps,maxiter)

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Thread

Function defined by a while loop Antonio Lo Turco <antonio.lo.turco@gmail.com> - 2011-06-27 02:50 -0700
  Re: Function defined by a while loop James Waldby <not@valid.invalid> - 2011-06-27 16:21 +0000
    Re: Function defined by a while loop Mauro <pippo@hotmail.com> - 2011-06-28 11:48 +0200
  Re: Function defined by a while loop Hans-Bernhard Bröker <HBBroeker@t-online.de> - 2011-06-27 22:00 +0200
    Re: Function defined by a while loop Mauro <pippo@hotmail.com> - 2011-06-28 11:56 +0200

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