# Circle

From JSXGraph Wiki

Revision as of 17:52, 17 September 2008 by 84.147.86.108 (talk) (New page: == Circle through two points == One possibility to construct a circle is to give its center and a point defining its radius. Lets construct two points "A" and "B". <source lang="javascript"> var b...)

## Circle through two points

One possibility to construct a circle is to give its center and a point defining its radius. Lets construct two points "A" and "B".

```
var b = JXG.JSXGraph.initBoard('jxgbox', {originX: 200, originY: 100, unitX: 50, unitY: 50});
var p1 = board.createElement('point',[-1,1], {name:'A',style:6});
var p2 = board.createElement('point',[2,-1], {name:'B',style:6});
```

Then we construct a circle through "A" and "B". The setting of a new color and changing the stroke-width is not necessary.

```
var li = brd.createElement('circle',["A","B"], {strokeColor:'#00ff00',strokeWidth:2});
```

Generally it is better to use JavaScript variables and not Geometry-Element names when constructing. Now, we do the same examples with JavaScript variables. To show another variation, we use a dashed stroke style.

```
var ci2 = brd2.createElement('circle',[p1,p2], {strokeWidth:3, dash:2});
```