# Cubic spline interpolation

From JSXGraph Wiki

Constructs a cubic spline through given points. Points can be added by clicking on "Add point".

### References

### The underlying JavaScript code

```
var board = JXG.JSXGraph.initBoard('box', {boundingbox: [-5, 10, 7, -5], axis:true});
var p = [];
p[0] = board.create('point', [-1,2], {size: 4, face: 'o'});
p[1] = board.create('point', [0,-1], {size: 4, face: 'o'});
p[2] = board.create('point', [1,0], {size: 4, face: 'o'});
p[3] = board.create('point', [2,1], {size: 4, face: 'o'});
var c = board.create('spline', p, {strokeWidth:3});
var g = board.create('glider', [1.5,0,c], {name:'',style:8});
var t = board.create('tangent', [g], {dash:2,strokeColor:'#aa0000'});
function addPoint() {
p.push(board.create('point',[(Math.random()-0.5)*10,(Math.random()-0.5)*3],{size: 4, face: 'o'}));
board.update();
}
```