permute.c

/* 
 * Copyright (c) 2000, 2001 Thomas E. Burge.  All rights reserved.
 * 
 * Affine (R) is a registered trademark of Thomas E. Burge
 *
 * THIS SOFTWARE IS DISTRIBUTED "AS-IS" WITHOUT WARRANTY OF ANY KIND
 * AND WITHOUT ANY GUARANTEE OF MERCHANTABILITY OR FITNESS FOR A 
 * PARTICULAR PURPOSE.  
 *
 * In no event shall Thomas E. Burge be liable for any indirect or
 * consequential damages or loss of data resulting from use or performance 
 * of this software.
 * 
 * Permission to use, copy, modify, distribute, and sell this software and 
 * its documentation for any purpose is hereby granted without fee, provided
 * that the following copyright notices and this permission notice appear in
 * all copies of the software and related documentation:
 *
 *                 The Affine (R) Libraries and Tools are 
 *                Copyright (c) 1995-2001 Thomas E. Burge.  
 *                          All rights reserved.
 *         Affine (R) is a registered trademark of Thomas E. Burge.
 *
 * Also refer to any additional requirements presently set by Pixar 
 * in regards to the RenderMan (R) Interface Procedures and Protocol.
 *
 *
 * Affine Toolkit
 *
 * FILE:  permute.c
 *
 * DESCRIPTION:  Prints a table of randomly distributed numers from 0 to 2048.
 * 
 *    References:
 *
 *    History:
 *
 *
 *         The RenderMan (R) Interface Procedures and Protocol are:
 *                    Copyright 1988, 1989, Pixar
 *                        All Rights Reserved
 *
 *             RenderMan (R) is a registered trademark of Pixar
 */
#include <stdio.h>

static unsigned int idum=1;

void setseed(unsigned int seed)
{
   idum = seed;
}

int getrandom( int max )
{
   /* Numerical Recipes in C, Second Edition, page 284. */
   idum = 1664525*idum + 1013904223;

   max++;

   return idum % max;
}

int main(int argc, char **argv) 
{
   unsigned int  P[2048];
   int           i,j,k,n;

   if (argc==2)
      setseed(atoi(argv[1]));

   for (i=0;i<2048;i++)
      P[i] = i;

   for (n=0;n<11;n++)
   {
      for (i=0;i<2048;i++)
      {
         j = getrandom(2047);
         k = P[j];
         P[j] = P[i];
         P[i] = k;
      }
   }

   printf("   ");   
   for (i=0;i<2048;i++)
   {
      printf("%4u, ",P[i]);
      if (i%10==9)
         printf("\n   ");
   }
   printf("\n");

   return 0;
}