#include <stdio.h> #include <stdlib.h> #include <math.h> int main(int argc, char ** argv) { double t, T, deltat; double x, y, z, x0, y0, z0, x1, y1, z1; FILE *gp; double s, b, r; double vis; if (argc < 3) { printf("Errore! Il programma si usa così: %s <x0> <T>\n", argv[0]); exit(1); } s = 10; b = 8./3; r = 28; x0=atof(argv[1]); T = atof(argv[2]); y0=1; z0=1; deltat = 0.001; vis = 0.01; x = x0; y = y0; z = z0; for (t=0; t<T; t+= deltat) { x1 = x + s*(y-x)*deltat; y1 = y + (x*(r-z)-y)*deltat; z1 = z + (x*y - b*z)*deltat; x = x1; y = y1; z = z1; if (fmod (t,vis) < deltat) { printf("%f %f %f %f\n", t, x, y, z); } } }