A negative angle in a clockwise direction

						var board = JXG.JSXGraph.initBoard('box1', {
boundingbox: [-10, 10, 10, -10],showNavigation:false, showcopyright: false, axis: false,
});

var p1 = board.create('point', [-6.0, -3.0],{label:{offset:[-10,-10]}});
var p2 = board.create('point', [2.0, 4],{label:{offset:[10,5]}});

var p3 = board.create('point', [3, -3],{label:{offset:[-15,-10]}});


var l1 = board.create('segment', [p1, p2]);
var l2 = board.create('segment', [p1,p3]);

var a1 = board.create('angle', [p3, p1, p2],{name:'',radius:5, lastArrow:{type: 1, size: 5},label:{offset:[30,0]}});

var g1 = board.create('glider', [-2, 0, l1],{face:'',name:''});
var g2 = board.create('glider', [-2, 0, l2],{face:'',name:''});
var arc1 = board.create('minorarc',[p1,g1,g2],
          {fixed: false, strokeWidth:2, lastArrow:{type:2, size: 5}});