Package cnuphys.swim

Class DefaultDerivative

java.lang.Object

cnuphys.swim.DefaultDerivative

All Implemented Interfaces:

IDerivative

public class DefaultDerivative
extends Object
implements IDerivative

Constructor Summary

Constructors

Constructor	Description
DefaultDerivative(int charge, double momentum, FieldProbe field)	The derivative for swimming through a magnetic field

Method Summary

Modifier and Type	Method	Description
void	derivative(double s, double[] u, double[] du)	Compute the derivatives given the value of s (path length) and the values of the state vector.
void	set(int charge, double momentum, FieldProbe field)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

DefaultDerivative

public DefaultDerivative(int charge,
 double momentum,
 FieldProbe field)

The derivative for swimming through a magnetic field

Parameters:

charge - -1 for electron, +1 for proton, etc.

momentum - the magnitude of the momentum.

field - the magnetic field

Method Details

set

public void set(int charge,
 double momentum,
 FieldProbe field)

derivative

public void derivative(double s,
 double[] u,
 double[] du)

Compute the derivatives given the value of s (path length) and the values of the state vector.

Specified by:

derivative in interface IDerivative

Parameters:

s - the value of the independent variable path length (input).

u - the values of the state vector ([x,y,z, tx = px/p, ty = py/p, tz = pz/p]) at s (input).

du - will be filled with the values of the derivatives at s (output).