how to erase old graph before new dra

[kiga01]

hi guys, anyone knows how i can clear the canvas bejore y draw new graph? this is how i create new graphs

var lineChartData = {
labels : mname,
datasets : [
{
label: "Ventas año "+ year,
fillColor : "rgba(220,220,220,0.2)",
strokeColor : "rgba(220,220,220,1)",
pointColor : "rgba(220,220,220,1)",
pointStrokeColor : "#fff",
pointHighlightFill : "#fff",
pointHighlightStroke : "rgba(220,220,220,1)",
data : array
},
]
}

var ctx = document.getElementById("myChart").getContext("2d");
var myLineChart = new Chart(ctx).Line(lineChartData, {
    responsive: true,
    //bezierCurve : false,
     bezierCurveTension : 0.1,
});

and how can i add another curve to the existing canvas?

[nnnick]

As mentioned in #559, you'd call myLineChart.destroy().

Not sure I understand what you mean by adding another curve? Do you mean point?

[kiga01]

sorry, i didnt explain myself well, but alredy solve it, i just erase the canvas and make new one before each draw