#include <stdio.h>
#include <stdlib.h>
#include <math.h>


const double g 	= 9.8; 	//!< constante de gravité
double       L 	= 1.0;  	//!< longueur du pendule
double	 alpha	= 3.14/2.0;	//!angle d'inclinaison du systeme(ou du vecteur gravite)
double m =1.0;
#define N 1000
int main ()
{
	FILE *fp,*fp2;
	
	
	
	int k;
	int i=0;
	double em=1;
	double pi=2*asin(1);
	double vphi=0.5;
	for(em=0.0;em<5.0;em+=0.5)
	{
		
		char  filename[20];
		char  filename2[20];
		i++;
		//-- creation des noms des fichiers multiples 
		
		sprintf(filename,"pit%d.dat", i );
		fprintf(stderr,"%s\n",filename);
		fp  = fopen( filename, "w" );		
		sprintf(filename2,"pitt%d.dat", i );
		fprintf(stderr,"%s\n",filename2);
		fp2  = fopen( filename2, "w" );	
	
		for(k=1;k<N;k++)
		{

			double theta= pi *k/((double)N) +1e-2;
					
			double a=sin(theta)*sin(theta);	
			double j=L*L*a*vphi*vphi;
			
			double vtheta=sqrt(2*cos(theta)*(g/L)-(j*j/(L*L*a))+em);
			
			fprintf (fp, "%0.16lf  %0.16lf  \n", theta , vtheta );
			
			fprintf (fp2, "%0.16lf  %0.16lf  \n", theta , -vtheta);
		}
	}
	fclose(fp);
	fclose(fp2);
	
	return 0;
}