Wpt[] pts) throws IOException {
OutputStreamWriter ow = new OutputStreamWriter(os, "utf-8");
try {
SvgPlot plot = getPlot(x, y, title, pts);
configurePlot(plot, x, y);
plot.plot(ow);
ow.flush();
} catch (FunctionEvaluationException ex) {
// should never happen.
throw new Error(ex);
}