def _draw_curves(self, selected_curves):
n_attr = len(self.attributes)
for color, y_values in sorted(selected_curves.items()):
n_rows = int(len(y_values) / n_attr)
x_values = list(range(n_attr)) * n_rows
curve = OWCurve()
curve.set_style(OWCurve.Lines)
curve.set_color(QColor(*color))
curve.set_segment_length(n_attr)
curve.set_data(x_values, y_values)
curve.attach(self)
