// Calculation Program for displaying five egg curves 3 (Suugaku-Dokusyuu-Juku's), 18(Fri.) Sep., 2009



// An ellipsoid in the case of a = c , and a circle in the case of b = 0 .



// file name: egg_shaped_curve_3b.c



// recommended values: a = 1.35, b = 1.15, c = 0.5



#include< stdio.h>

#include< math.h>



void main(void)

{

	double x,y,r,a,b,c,db,bmin,bmax,pai;

	double t,dt;

	int i,imax,n,nmax;

	double xx[10][2001],yy[10][2001];// Take care of the upper limit of storage memory capacitance.



	FILE *fp;



// Setting of the constants

	pai=3.1415927;



	a=1.35;

	b=1.15;

	c=0.5;



	bmin=b-0.2;

	bmax=b+0.2;

	db=(bmax-bmin)/5;



	printf("a=%f\n\n",a);

	 

// Setting of the other parameter

	dt=pai/500;// the plotting interval of the phase angle



// execution of calculation

	i=0;

	for(t=0;t<=2*pai+0.001;t=t+dt)

	{

		i++;

		n=0;



		for(b=bmin;b<=bmax+0.001;b=b+db)

		{

			n++;



			r=(a+c+(c-a)*cos(t))/2;

			x=b*cos(t)/2+r*cos(t);

			y=r*sin(t);



			yy[n][i]=y;

			xx[n][i]=x;

			printf("i=%d,x=%f,y=%f\n",i,x,y);

		}

	}

	imax=i;

	nmax=n;



// writing the calculated coordinates data of the curve into a textfile

	fp=fopen("egg-shaped curve.txt","w");

	if(fp==NULL)

		{

		printf("FILE OPEN ERROR\n");

		}

	else

		{

		for(i=1;i<=imax;i++)

			{

			fprintf(fp,"%f,%f,%n,%f,%f,%n,%f,%f,%n,%f,%f,%n,%f,%f\n",xx[1][i],yy[1][i],"",xx[2][i],yy[2][i],"",xx[3][i],yy[3][i],"",xx[4][i],yy[4][i],"",xx[5][i],yy[5][i]);

			}

		fflush(fp);

		fclose(fp);

		}

	printf("end\n");

}// the end of the program