Interactive JessieScript

A(1,1);B(2,2.5);C(1,3);[AB];k(B,[AC]);

Possible elements:

Construction	Description
A(1,1)	Point with name 'A' at position (1,1)
ZY(0.5|1)	Point with name 'ZY' at position (0.5,1)
]AB[	straight line through points A and B
[AB[	ray through points A and B, stopping at A
]AB]	ray through points A and B, stopping at B
[AB]	segment through points A and B
g=[AB]	segment through points A and B, named by 'g'
k(A,1)	circle with midpoint A and radius 1
k(A,B)	circle with midpoint A through point B on the circle line
k(A,[BC])	circle with midpoint A and radius defined by the length of the (not necessarily existing) segement [BC]
k_1=k(A,1)	circle with midpoint A and radius 1, named by 'k_1'

The different elements have to be separated by semicolon.

The JavaScript code

var board, construction = [];
board = JXG.JSXGraph.initBoard('box', {grid:true, boundingbox:[-1,6,11,-3], keepaspectratio:true, axis:true});

function construct() {
    var t = document.getElementById('input').value;
    board.suspendUpdate();
    construction.push(board.construct(t));
    board.unsuspendUpdate();
}