Quadratic

All Known Implementing Classes:

TransformQuadratic
```
public interface Quadratic
```
Define a second-order quadratic operation on a Vector 0.5 x'Hx + b'x where H is a positive semidefinite quadratic and b is a linear gradient.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Vect`	`getB()`	Get the linear gradient term b of the quadratic expression.
`void`	`inverseHessian(Vect x)`	Multiply vector by an approximate inverse of the Hessian.
`void`	`multiplyHessian(Vect x)`	Multiply vector by the quadratic Hessian H.

- Method Detail
  - multiplyHessian
```
void multiplyHessian(Vect x)
```
    Multiply vector by the quadratic Hessian H. Perform the operation in-place.
    
    Parameters:
    
    x - Vector to be multiplied and modified.
  - inverseHessian
```
void inverseHessian(Vect x)
```
    Multiply vector by an approximate inverse of the Hessian. Perform the operation in-place. This method is useful to speed convergence. An empty implementation is equivalent to an identity.
    
    Parameters:
    
    x - Vector to be multiplied and modified.
  - getB
```
Vect getB()
```
    Get the linear gradient term b of the quadratic expression. The recipient receives a unique copy that must be disposed.
    
    Returns:
    
    The vector b where the quadratic is x'Hx + b'x