cProg,
There are few issues with the code.
– Y value you are assigning is a String instead of a Number.
– drawChart method is not defined
– dataPoints is null Array
What you can do is
– Assign a Number as y-value.
– Define a method drawChart to update dataPoints as show below.
function drawChart(dataPoints){
chart.options.data[0].dataPoints = dataPoints;
chart.render();
}