code: public static PlotCanvas plot(double[][] data, Line.Style style, Color color) {
          return plot(null, data, style, color);
      }
docs: Create a plot canvas with the poly line plot of given data.
  @param data a n-by-2 or n-by-3 matrix that describes coordinates of points.
  @param style the stroke style of line.
  @param color the color of line.