Package org.apache.commons.math3.optimization.general

Enum ConjugateGradientFormula

java.lang.Object
java.lang.Enum<ConjugateGradientFormula>
org.apache.commons.math3.optimization.general.ConjugateGradientFormula
All Implemented Interfaces:
Serializable, Comparable<ConjugateGradientFormula>, java.lang.constant.Constable
@Deprecated public enum ConjugateGradientFormula extends Enum<ConjugateGradientFormula>
Deprecated.
As of 3.1 (to be removed in 4.0).
Available choices of update formulas for the β parameter in NonLinearConjugateGradientOptimizer.

The β parameter is used to compute the successive conjugate search directions. For non-linear conjugate gradients, there are two formulas to compute β:

  • Fletcher-Reeves formula
  • Polak-Ribière formula
On the one hand, the Fletcher-Reeves formula is guaranteed to converge if the start point is close enough of the optimum whether the Polak-Ribière formula may not converge in rare cases. On the other hand, the Polak-Ribière formula is often faster when it does converge. Polak-Ribière is often used.

Since:
2.0
See Also:

  • Enum Constant Details

  • Method Details

    • values

      public static ConjugateGradientFormula[] values()
      Deprecated.
      Returns an array containing the constants of this enum type, in the order they are declared.
      Returns:
      an array containing the constants of this enum type, in the order they are declared

    • valueOf

      public static ConjugateGradientFormula valueOf(String name)
      Deprecated.
      Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
      Parameters:
      name - the name of the enum constant to be returned.
      Returns:
      the enum constant with the specified name
      Throws:
      IllegalArgumentException - if this enum type has no constant with the specified name
      NullPointerException - if the argument is null