beginners/oneoverx.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <math.h>
   4
   5 int main(int argc,char **argv) {
   6
   7         int i;
   8
   9         double c,a,o,f;
  10
  11         a=atof(argv[1]);
  12         c=(1.0-sqrt(1+4*a))/2.0; // -!
  13         o=a/(1-c);
  14
  15         printf("; f(x) = a / (x+o)  +  c  (a:%f o:%f c:%f)\n",a,o,c);
  16
  17         for(i=255;i>=0;i--) {
  18                 f=a/(1.0*i/255+o)+c;
  19                 printf("; %d - %d\n",255-i,255-i+1);
  20                 printf(".db 0x%0x, ",(int)(f*255));
  21                 i-=1;
  22                 f=a/(1.0*i/255+o)+c;
  23                 printf("0x%0x\n",(int)(f*255));
  24         }
  25
  26         return 0;
  27 }
  28