### Syntax

`hPatch = swplot.circle(r0, n, R)`

`hPatch = swplot.circle(r0, n, R, nPatch)`

`hPatch = swplot.circle(handle, ...)`

### Description

`hPatch = swplot.circle(r0, n, R)`

creates a triangulated patch of a
surface of a circle in 3D, defined by the center position, normal vector
and radius.

`hPatch = swplot.circle(handle, ...)`

adds the patch object to a given axis
if `handle`

is an axis handle or adds the arrow to an existing
patch object, if the given `handle`

points to a patch object.

### Examples

Draw 100 random unit circle surfaces with center at and random normal vector.

```
swplot.figure
N = 100
swplot.circle(zeros(3,N),2*rand(3,N)-1,1)
swplot.zoom(30)%
```

### Input Arguments

`handle`

- Handle of an axis or triangulated patch object. In case of patch object, the constructed faces will be added to the existing object.
`r0`

- Center position of the circle in a column vector. Multiple circles can be defined using a matrix with dimensions of where each column defines a circle center.
`n`

- Column vector with 3 elements, normal to the circle surface. Multiple
circles can be defined using a matrix with the same dimensions as
`r0`

parameter. `R`

- Radius of the circle, scalar or row vector with number of elements.
`nPatch`

- Number of points on the circle circumference, default value is stored in
`swpref.getpref('npatch')`

. The generated patch will contain number of faces and vertices.