// Calculation Program for calculating shape of a flower with the use of a Cardioid (1), July 15, 2012
// file name: flower_g.c
#include< stdio.h>
#include< math.h>
void main(void)
{
double a,pi;// "a" is the constant of original Cardioid and pi=3.1415...
double t,dt;// the phase angle and its increment of the Cardioid before the conversion respectively
double r,z;// the moving radius and the phase angle of the Cardioid after some conversion respectively
double f;// the phase angle of the Cardioid after the final conversion into a horned one (using as a petal of a flower)
int n;// a desired numbers of petals of a flower
double alpha;// the angle for the horned Cardioid (used as that alpha=2*pi/n (using as "alpha=pi/n" in this C program)
double tmin,tmax;// the minimum and maximum values of the phase angle "t" respectively
int i,imax,j;
double x,y;// the orthogonal coordinates of a petal before contraction or expansion
float b;// the ratio of contraction or expansion of a petal in the length direction
float c;// the radius of a center circle
double beta;// angular range to be occupied by a petal around the center circle
double dbeta;// increment of "beta"
double k;// magnification factor of the criterion angle "alpha=2*pi/n" where 0 < k
double l;// magnification factor of the angular range "beta" where 0 < l
double rr;// the moving radius of a petal after contraction or expansion
double ff;// the phase angle of a petal after contraction or expansion
double p;// phase angle of center circle
double dp;// increment of "p"
int nz;// division numbers of both phases "z" and "beta"
int m;// count numbers of the increment of "beta"
double xx[30001],yy[30001];// Take care of the upper limit of storage memory capacitance.
FILE *fp;
// setting of the constants
pi=3.14159265;
a=1.;
// setting of the other parameters
printf("Input the numbers of petals. \n n=? ");
scanf("%d",&n);
printf("n=%d\n",n);
printf("\n");
alpha=2*pi/n;// the angle for the horned Cardioid as a petal
beta=alpha;// fundamentally criteria value of "beta" is supposed to be equal to "alpha".
k=1.5;// k=1 magnification factor of the criterion angle 'alpha=2*pi/n' where 0 < k
l=0;// l=0 magnification factor of the criterion angular range "beta" where 0 < l
alpha=k*alpha;// the magnificated angle of the botom of the petal
beta=l*beta;// the magnificated angular range to be occupied by a petal around the center circle
printf("Input the ratio of contraction or expansion of a petal in the length direction. \n b= ? ");
scanf("%f",&b);
printf("b=%f\n",b);
printf("\n");
printf("Input the radius of the center circle. \n c= ? ");
scanf("%f",&c);
printf("c=%f\n",c);
printf("\n");
tmin=-pi/2;
tmax=3*pi/2;
nz=200;
dt=(tmax-tmin)/nz;// // plotting interval of "t"
dbeta=beta/nz;// increment of "beta"
dp=2*pi/n/20;// increment of "p"
// execution of calculation
i=0;
for(j=1;j<=n;j++) // sweep of n numbers of petals
{
m=0;
for(t=tmin;t<=tmax+dt;t=t+dt) // sweep of phase angle "t" of the each petal
{
i++;
m++;
if(t>(3*pi/2-dt) && t<(3*pi/2+dt))
{
r=0.;
z=-pi/2;
}
else
{
if(t>(-pi/2-dt) && t<(-pi/2+dt))
{
r=0.;
z=pi/2;
}
else
{
r=a*sqrt((5-3*sin(t))*(1+sin(t)));
z=asin(a*(1-sin(t))*cos(t)/r);
}
}
f=-alpha*z/pi+pi/2;
x=r*cos(f);
y=b*r*sin(f);
rr=sqrt(x*x+y*y);
if(fpi||ff<0)
{
ff=atan(b*tan(f));
}
*/
}
}
ff=ff+2*pi*(j-1)/n;
xx[i]=r*cos(ff)+c*cos(2*pi*(j-1)/n+pi/2-beta/2+m*dbeta);
yy[i]=r*sin(ff)+c*sin(2*pi*(j-1)/n+pi/2-beta/2+m*dbeta);
printf("i=%d,x=%f,y=%f\n",i,xx[i],yy[i]);
}
if(l<=1) // Simply for drawing an additional circle of underlying petal.
{
for(p=2*pi*(j-1)/n+pi/2+beta/2;p<2*pi*j/n+pi/2-beta/2+dp;p=p+dp)
{
i++;
xx[i]=c*cos(p);
yy[i]=c*sin(p);
printf("i=%d,x=%f,y=%f\n",i,xx[i],yy[i]);
}
}
else
{
for(p=2*pi*(j-1)/n+pi/2+beta/2;p>2*pi*j/n+pi/2-beta/2-dp;p=p-dp)
{
i++;
xx[i]=c*cos(p);
yy[i]=c*sin(p);
printf("i=%d,x=%f,y=%f\n",i,xx[i],yy[i]);
}
}
}
imax=i;
// writing the calculated coordinates data of the curve into a textfile named "flower_g.txt"
fp=fopen("flower_g.txt","w");
if(fp==NULL)
{
printf("FILE OPEN ERROR\n");
}
else
{
for(i=1;i<=imax;i++)
{
fprintf(fp,"%f,%f\n",xx[i],yy[i]);
}
fflush(fp);
fclose(fp);
}
printf("end\n");
}// the end of the program
RETURN