Lpc2000

Just to finish the discussion with a useful result.

from the chapter 7 of:
Link to online-Version: http://www.library.cornell.edu/nr/cbookcpdf.html 
respectively the mentioned chapter: http://www.library.cornell.edu/nr/bookcpdf/c7-4.pdf 

A very simple and efficient

unsigned long idum = 0; 
... 
idum = 1664525L*idum + 1013904223L; 

Varuzhan


  ----- Original Message ----- 
  From: Marko Pavlin 
  To: lpc2000@yahoogroups.com 
  Sent: Tuesday, May 03, 2005 3:23 PM
  Subject: Re: [lpc2000] rand() function


  Hello!

  I found TEA very useful as random number generator.

  http://www.simonshepherd.supanet.com/tea.htm

  Marko


  Paul Curtis wrote:
  > Hi,
  > 
  >  > The standard rand() function of many compilers (Keil, etc.)
  >  > return pseudorandom integer in range 0 to 32767.
  >  > 1. Is the period of such pseudorandom generators equal to
  >  > 2^15, or it is more?
  > 
  > Good question.  Usually these implementations are based on linear
  > congruence, i.e next_random = (seed*x+y) modulo a smaller number.
  > 
  >  > 2. Who has an efficient algorithm for 2^31 period rand()
  >  > function? Both assembler and C realizations are of interest.
  > 
  > Try Google, there are many PRANGs.  It really depends upon your
  > application what type of PRANG to employ e.g. uniform random numbers,
  > Gaussian random numbers, and so on.  Higher quality random numbers
  > usually require more expensive computations and are, therefore, less
  > efficient.
  > 
  > As with implementation of transcendental and logarithmic approximations,
  > there is more than one way to skin a cat, so just consider rand() a
  > low-quality function that fulfils the requirements of the ISO standard.
  > 
  > Boost has an appealing random number library:
  > 
  > http://www.boost.org/libs/random/
  > 
  > --
  > Paul Curtis, Rowley Associates Ltd  http://www.rowley.co.uk
  > CrossWorks for MSP430, ARM, AVR and (soon) MAXQ processors
  > 
  > ------------------------------------------------------------------------
  > *Yahoo! Groups Links*
  > 
  >     * To visit your group on the web, go to:
  >       http://groups.yahoo.com/group/lpc2000/
  >        
  >     * To unsubscribe from this group, send an email to:
  >       lpc2000-unsubscribe@yahoogroups.com
  >       <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe>
  >        
  >     * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
  >       Service <http://docs.yahoo.com/info/terms/>. 
  > 
  > 


------------------------------------------------------------------------------
  Yahoo! Groups Links

    a.. To visit your group on the web, go to:
    http://groups.yahoo.com/group/lpc2000/
      
    b.. To unsubscribe from this group, send an email to:
    lpc2000-unsubscribe@yahoogroups.com
      
    c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. 



[Non-text portions of this message have been removed]