ptolemy.math
Class SignalProcessing.PolynomialSampleGenerator

java.lang.Object
  ptolemy.math.SignalProcessing.PolynomialSampleGenerator

All Implemented Interfaces:

DoubleUnaryOperation

Enclosing class:

SignalProcessing

public static class SignalProcessing.PolynomialSampleGenerator
extends java.lang.Object
implements DoubleUnaryOperation

This class generates samples of a polynomial. The function computed is:

  h(t) = a0 + a1t + a2t2 + ...
         + an-1tn-1
  

or

  h(t) = a0 + a1t-1
         + a2t-2 + ...
         + an-1t-(n-1)
  

depending on the direction specified.

Field Summary

private double[]	_coefficients
private int	_coeffLength
private int	_direction

Constructor Summary

SignalProcessing.PolynomialSampleGenerator(double[] coefficients, int direction)
Construct a PolynomialSampleGenerator.

Method Summary

double

operate(double time) Return a sample of the line, sampled at the specified time.

Methods inherited from class java.lang.Object

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

Field Detail

_coefficients

private final double[] _coefficients

_coeffLength

private final int _coeffLength

_direction

private final int _direction

Constructor Detail

SignalProcessing.PolynomialSampleGenerator

public SignalProcessing.PolynomialSampleGenerator(double[] coefficients,
                                                  int direction)

Construct a PolynomialSampleGenerator. The input argument is an array of doubles a[0] = a₀ .. a[n-1] = a_n-1 used to compute the formula : h(t) = a₀ + a₁t + ... + a_n-1t^n-1 The array of doubles must be of length 1 or greater. The array of doubles is copied, so the user is free to modify it after construction. The exponents on t in the above equation will all be negated if the direction parameter is -1; otherwise the direction parameter should be 1.

Parameters:

coefficients - An array of double coefficients.

direction - 1 for positive exponents, -1 for negative exponents.

Method Detail

operate

public final double operate(double time)

Return a sample of the line, sampled at the specified time. Note that at time = 0, with a negative direction, the sample will be positive or negative infinity.

Specified by:

operate in interface DoubleUnaryOperation

Parameters:

time - The operand.

Returns:

The results of the operation.