code: public static int compare(double a, double b, double delta) {
          if (equals(a, b, delta)) {
              return 0;
          }
          return Double.compare(a, b);
      }
docs: Compares two double values up to some delta.
  
  @param a
  @param b
  @param delta
  @return The value 0 if a equals b, a value greater than 0 if if a > b, and a value less than 0 if a < b.