Delete main.c

src/main.c

-#include <stdio.h>
-#include <stdlib.h> 
-#include <math.h>
-
-//compile options gcc -O2 main.c -Wall -lm
-
-typedef struct {
-    double x[3]; 
-    double v[3]; 
-    double a[3]; 
-    double mass; 
-} Planet; 
-
-Planet Planets[] = {
-    {
-        {0,0,0},
-        {0,0,0},
-        {0,0,0},
-        1.98847*pow(10,30)
-    },
-    {
-        {149597870700,0,0},
-        {0,30080,0},
-        {0,0,0},
-        5.9722*pow(10,24)
-    }
-};
-//TODO add softening factor
-static inline double distance( const double x1[3], const double x2[3]) {
-    const double x = x1[0] - x2[0];
-    const double y = x1[1] - x2[1];
-    const double z = x1[2] - x2[2];
-    
-    return sqrt(x*x + y*y + z*z);
-    
-}
-double energy(int n, double G){
-    double e;
-    int i=0, j=0, k=0;
-    e = 0.0;
-
-    for(i=0; i<n; i++){
-        for(k=0; k<3; k++){
-            e += 0.5 * Planets[i].mass * Planets[i].v[k] * Planets[i].v[k];
-        }
-        for(j=i+1; j < n; j++) {
-            double  dist = distance(Planets[i].x, Planets[j].x);
-            e -= (G * Planets[i].mass * Planets[j].mass) / dist;
-        }
-    }
-    return e;
-}
-
-
-
-int main(int argc, char * argv[]) {
-
-
-    const long steps = atoi(argv[1]);
-    /*if (argc == 1) {
-        const long steps = atoi(argv[1]); 
-    } else {
-        const long steps = 10000;
-    }*/
-    //FILE *output = fopen("output.xyz", "w+"); 
-    FILE *output = fopen("test", "w+"); 
-    //defer fclose(output);
-    if (output == NULL) {
-        printf("HELP\n COULDNT OPEN FILE\nSIGSEVV"); //TODO stop here 
-    } else {
-        printf("Output File opened");
-    }
-    //this could also be done via the preprocessor
-    const int noOfBodies = sizeof(Planets)/sizeof(Planet); 
-    printf("size: %d", noOfBodies);
-    const double G = 6.6743015*pow(10,-11);
-    const double dt = 0.1; 
-    printf("energy before: %.lf\n", energy(noOfBodies, G));
-    
-    
-    
-    
-     
-    //double vx, vy, vz; 
-    long run = 0;
-    //double acc_buff[3]; 
-   
-    
-    while (run < steps) {
-        for (int l = 0; l < noOfBodies; l++) {
-            Planets[l].v[0] += 0.5 * Planets[l].a[0]* dt;
-            Planets[l].v[1] += 0.5 * Planets[l].a[1]* dt;
-            Planets[l].v[2] += 0.5 * Planets[l].a[2]* dt;
-            if (run %(long int) pow(10,7)== 0) {
-                //fprintf(output, "%d    %lf    %lf    %lf\n", index, Planets[index].x[0], Planets[index].x[1], Planets[index].x[2]);
-                fprintf(output, "%lf,%lf,%lf,", Planets[l].x[0], Planets[l].x[1], Planets[l].x[2]);
-            }
-        }
-        for (int k = 0; k < noOfBodies; k++) {
-            Planets[k].x[0] += dt * Planets[k].v[0];
-            Planets[k].x[1] += dt * Planets[k].v[1];
-            Planets[k].x[2] += dt * Planets[k].v[2];
-            Planets[k].a[0] = 0;
-            Planets[k].a[1] = 0;
-            Planets[k].a[2] = 0;
-            //printf("%d @ %d; ---x: %lf, y: %lf, z: %lf\n\n",run, k, Planets[k].x[0], Planets[k].x[1], Planets[k].x[2]);
-        }
-        
-        for (int i = 0; i < noOfBodies; i++) {
-            for (int j = i+1; j < noOfBodies; j++) {
-                    double  dist = distance(Planets[i].x, Planets[j].x);
-                    double a = G/pow(dist, 3);
-                    
-                    //this might be the wrong way.......
-                    Planets[i].a[0] += a * Planets[j].mass * ( Planets[j].x[0] - Planets[i].x[0] );
-                    Planets[i].a[1] += a * Planets[j].mass * ( Planets[j].x[1] - Planets[i].x[1] );
-                    Planets[i].a[2] += a * Planets[j].mass * ( Planets[j].x[2] - Planets[i].x[2] );
-                    Planets[j].a[0] += a * Planets[i].mass * ( Planets[i].x[0] - Planets[j].x[0] );
-                    Planets[j].a[1] += a * Planets[i].mass * ( Planets[i].x[1] - Planets[j].x[1] );
-                    Planets[j].a[2] += a * Planets[i].mass * ( Planets[i].x[2] - Planets[j].x[2] );
-                    //printf("%lf\n", Planets[i].a[1]);
-            }
-        }
-        if (run %(long int) pow(10,7)== 0) {
-                //fprintf(output, "%d    %lf    %lf    %lf\n", index, Planets[index].x[0], Planets[index].x[1], Planets[index].x[2]);
-            fprintf(output, "\n" );
-        }
-       
-        for (int m = 0; m < noOfBodies; m++) {
-            Planets[m].v[0] += 0.5 * Planets[m].a[0]* dt;
-            Planets[m].v[1] += 0.5 * Planets[m].a[1]* dt;
-            Planets[m].v[2] += 0.5 * Planets[m].a[2]* dt;
-        }
-        run++;
-    }
-    printf("energy before: %.lf\n", energy(noOfBodies, G));
-    printf("distance: %lf\n", distance(Planets[0].x, Planets[1].x));
-    fclose(output);
-}
-