The easiest option to draw a circle, is - obviously - the ** rectangle** function.

```
%// radius
r = 2;
%// center
c = [3 3];
pos = [c-r 2*r 2*r];
rectangle('Position',pos,'Curvature',[1 1])
axis equal
```

but the curvature of the rectangle has to be set to **1**!

The `position`

vector defines the rectangle, the first two values `x`

and `y`

are the lower left corner of the rectangle. The last two values define width and height of the rectangle.

```
pos = [ [x y] width height ]
```

The lower left *corner* of the circle - yes, this circle has corners, imaginary ones though - is the **center** `c = [3 3]`

**minus the radius** `r = 2`

which is `[x y] = [1 1]`

. **Width** and **height** are equal to the **diameter** of the circle, so `width = 2*r; height = width;`

In case the smoothness of the above solution is not sufficient, there is no way around using the obvious way of drawing an actual circle by use of **trigonometric functions**.

```
%// number of points
n = 1000;
%// running variable
t = linspace(0,2*pi,n);
x = c(1) + r*sin(t);
y = c(2) + r*cos(t);
%// draw line
line(x,y)
%// or draw polygon if you want to fill it with color
%// fill(x,y,[1,1,1])
axis equal
```

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