package joptima;

/**
 * A {@link Function} of two arguments.
 * May or may not meaningfully implement {@link Function#calculate}.
 *
 * @author Dejan Vucinic <dvucinic@users.sourceforge.net>
 */
public interface Function2D extends Function {

  /**
   * Calculates the value of the function at the given x-y point using the
   * preset parameters.
   * @param x the x coordinate to calculate the function at
   * @param y the y coordinate to calculate the function at
   * @return the value of the function at the given x-y point
   */
  public double /* z = */ calculate(double x, double y);

}