LombPeriodogram (math 11.1.5 API)

java.lang.Object
- de.gsi.math.spectra.lomb.LombPeriodogram

```
public class LombPeriodogram
extends java.lang.Object
```
Class implements the computation of 'Lomb' periodograms. These allow to assess the spectral amplitudes of unequally spaced data (e.g. data sets with gaps or that consists of bursts of data) references: P. Vanicek, "Approximate Spectral Analysis by Least-Squares Fit", Astrophysics and Space Science 4 (1969) 387–391. N. R. Lomb, "Least-Squares Frequency Analysis of Unequally Spaced Data", in: Astrophysics and Space Science, Vol. 39, 1976, pp. 447–462. V. F. Pisarenko, "The retrieval of harmonics from a covariance function Geophysics", in: Royal Astronomical Society, Vol. 33, 1973, pp. 347–366.

Author:

rstein

Field Summary

Fields
Modifier and Type Field Description

protected static int START_THREADS

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static double[]`	`computeFrequencyRange(double[] time)`	Compute the optimal frequency and binning range based on the acquisition range (t_max-t_min) and the minimum non-zero sampling distance.
`static double[]`	`computePeridodogram(double[] t, double[] val)`	Lomb periodogram computation.
`static double[]`	`computePeridodogram(double[] t, double[] val, double[] testFrequencies)`	Lomb periodogram computation

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - START_THREADS
```
protected static final int START_THREADS
```
    See Also:
    
    Constant Field Values
- Method Detail
  - computeFrequencyRange
```
public static double[] computeFrequencyRange(double[] time)
```
    Compute the optimal frequency and binning range based on the acquisition range (t_max-t_min) and the minimum non-zero sampling distance.
    
    Parameters:
    
    time - time base vector
    
    Returns:
    
    vector containing frequency range
  - computePeridodogram
```
public static double[] computePeridodogram(double[] t,
                                           double[] val)
```
    Lomb periodogram computation. The maximum frequency and binning is derived from the acquisition range (t_max-t_min) and the minimum non-zero sampling distance.
    
    Parameters:
    
    t - the time indices
    
    val - the measurement
    
    Returns:
    
    vector containing Lomb-type Periodogram
  - computePeridodogram
```
public static double[] computePeridodogram(double[] t,
                                           double[] val,
                                           double[] testFrequencies)
```
    Lomb periodogram computation
    
    Parameters:
    
    t - the time indices
    
    val - the measurement
    
    testFrequencies - array containing the frequencies for which the spectra is being evaluated
    
    Returns:
    
    vector containing Lomb-type Periodogram