# ftp.nice.ch/pub/next/unix/developer/plplot.3.0.s.tar.gz#/plplot/examples/example03.c

```/* Illustration of 1-1 scaling for polar plot */
#include <stdio.h>
#include <math.h>

main()
{
int i,j;
double dtr, theta, dx, dy, r;
char text[3];
static FLOAT x0[361], y0[361];
static FLOAT x[361], y[361];

dtr = 3.141592654/180.0;
for (i=0; i<=360; i++) {
x0[i] = cos(dtr * i);
y0[i] = sin(dtr * i);
}

plstar(1,1);

/* Set up viewport and window, but do not draw box */

plenv(-1.3,1.3,-1.3,1.3,1,-2);
for (i=1; i<=10; i++) {
for (j=0; j<=360; j++) {
x[j] = 0.1*i*x0[j];
y[j] = 0.1*i*y0[j];
}

/* Draw circles for polar grid */

plline(361,x,y);
}

plcol(2);
for (i=0; i<=11; i++) {
theta = 30.0*i;
dx = cos(dtr*theta);
dy = sin(dtr*theta);

/* Draw radial spokes for polar grid */

pljoin(0.0,0.0,dx,dy);
sprintf(text,"%d",round(theta));

/* Write labels for angle */

if (dx >= 0)
plptex(dx,dy,dx,dy,-0.15,text);
else
plptex(dx,dy,-dx,-dy,1.15,text);
}

/* Draw the graph */

for (i=0; i<=360; i++) {
r = sin(dtr*(5*i));
x[i] = x0[i] * r;
y[i] = y0[i] * r;
}
plcol(3);
plline(361,x,y);

plcol(4);
plmtex("t",2.0,0.5,0.5,"#frPLPLOT Example 3 - r(#gh)=sin 5#gh");

/* Close the plot at end */

plend();
}

int
round(d)
double	d;
{
return((int)(d+0.5));
}
```

These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.