circle {berryFunctions} R Documentation

## Draw circle with a given radius

### Description

Draws a filled circle with a certain radius (in existing plot's units) using `polygon` and `sin`

### Usage

```circle(x, y, r, locnum = 100, ...)
```

### Arguments

 `x` x coordinate of points, numeric value of length 1 `y` y coordinate `r` radius of the circle in units of current plot. Can have two values for an ellipse. `locnum` number of calculated points on the circle (more means smoother but slower). DEFAULT: 100 `...` further arguments passed to `polygon`, like col, border, lwd

### Value

data.frame of coordinates, invisible

### Note

If circles look like ellipsis, use plot(... asp=1)

### Author(s)

Berry Boessenkool, berry-b@gmx.de, 2012

### See Also

`symbols`, `polygon`

### Examples

```
plot(1:20, type="n", asp=1)
circle(5,5, r=3)   # 1:1 aspect shows they're really circles and not ellipses.
circle(15,10, r=4, locnum=12, col=2, border=4, lwd=3)

# can not be vectorized:
x <- sample(1:20, 15) ;  y <- sample(1:20, 15) ; r <- runif(20)*3
circle(x,y,r, col=rgb(1,0.5,0,alpha=0.4), border=NA)
for(i in 1:15) circle(x[i],y[i],r[i], col=rgb(1,0.5,0,alpha=0.4), border=NA)

```

[Package berryFunctions version 1.20.1 Index]