kettenbruchentwicklung.c

   1 #include <stdio.h>
   2 #include <math.h>
   3 #include "g_plot.h"
   4
   5 #define INT .5
   6 #define GENAUIGKEIT .5
   7 #define GENAUIGKEIT_2 (GENAUIGKEIT*GENAUIGKEIT)
   8 #define PI M_PI
   9
  10 int main(int argc,char **argv) {
  11         double f_n=0,f_a=0;
  12         double A,A_1,A_2;
  13         double B,B_1,B_2;
  14         double a=0;
  15         int i;
  16         double x;
  17         int fd;
  18
  19         /* parse command line */
  20         if(argc!=2) {
  21                 printf("usage:\n");
  22                 printf("%s plotfile\n",argv[0]);
  23                 return -1;
  24         }
  25
  26         /* main init */
  27         x=0;
  28         fd=gp_init(argv[1]);
  29
  30         /* x loop */
  31         while(x<4*PI) {
  32
  33                 /* init */
  34                 A_1=0; A_2=x; A=x;
  35                 B_1=1; B_2=0; B=1;
  36                 i=1;
  37                 f_n=0;
  38                 f_n=f_a+2.0*GENAUIGKEIT;
  39                 /* loop bis y genuaigkeit */
  40                 while(!(((f_n-f_a)*(f_n-f_a))<GENAUIGKEIT_2)){
  41                         f_a=f_n;
  42                         i++;
  43                         a=(i>>1)*(i>>1)*x;
  44                         A=i*A_1+a*A_2;
  45                         B=i*B_1+a*B_2;
  46                         f_n=A/B;
  47                 }
  48                 printf("debug: x=%f, y=%f bei N=%d (a=%f)\n",x,f_n,i,a);
  49                 gp_add_data(fd,&f_n,1,1,TYPE_DOUBLE);
  50                 x+=INT;
  51         }
  52         gp_close(fd);
  53         return 1;
  54 }
  55