de.gsi.math.spectra

Class TSpectrum

java.lang.Object

de.gsi.math.spectra.TSpectrum

public class TSpectrum
extends Object

Original Author: Miroslav Morhac 27/05/99 clean up/java port: Ralph Steinhagen 18/04/18 THIS CLASS CONTAINS ADVANCED SPECTRA PROCESSING FUNCTIONS. ONE-DIMENSIONAL BACKGROUND ESTIMATION FUNCTIONS ONE-DIMENSIONAL SMOOTHING FUNCTIONS ONE-DIMENSIONAL DECONVOLUTION FUNCTIONS ONE-DIMENSIONAL PEAK SEARCH FUNCTIONS These functions were written by: Miroslav Morhac Institute of Physics Slovak Academy of Sciences Dubravska cesta 9, 842 28 BRATISLAVA SLOVAKIA email:fyzimiro@savba.sk, fax:+421 7 54772479 The original code in C has been repackaged as a C++ class by R.Brun The algorithms in this class have been published in the following references: [1] M.Morhac et al.: Background elimination methods for multidimensional coincidence gamma-ray spectra. Nuclear Instruments and Methods in Physics Research A 401 (1997) 113-132. [2] M.Morhac et al.: Efficient one- and two-dimensional Gold deconvolution and its application to gamma-ray spectra decomposition. Nuclear Instruments and Methods in Physics Research A 401 (1997) 385-408. [3] M.Morhac et al.: Identification of peaks in multidimensional coincidence gamma-ray spectra. Nuclear Instruments and Methods in Research Physics A 443(2000), 108-125. These NIM papers are also available as doc or ps files from: ftp://root.cern.ch/root/Spectrum.doc

ftp://root.cern.ch/root/SpectrumDec.ps.gz ftp://root.cern.ch/root/SpectrumSrc.ps.gz ftp://root.cern.ch/root/SpectrumBck.ps.gz The original source documentation as well as examples can be found at http://root.cern.ch/

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	fgAverageWindow
protected static int	fgIterations
protected int	fMaxPeaks
protected int	fNPeaks
protected double[]	fPosition
protected double[]	fPositionX
protected double[]	fPositionY
protected double	fResolution

Constructor Summary

Constructors

Constructor and Description
TSpectrum() The TSpectrum() default constructor
TSpectrum(int maxpositions, double resolution)

Method Summary

Modifier and Type	Method and Description
void	finalize() TSpectrum desctructor
int	getNPeaks()
double[]	getPeakX()
double[]	getPeakY()
static void	main(String[] argv)
int	Search(double[] hinX, double[] hinY, double[] houtX, double[] houtY, double sigma, String option, double threshold) ONE-DIMENSIONAL PEAK SEARCH FUNCTION This function searches for peaks in source spectrum in hin The number of found peaks and their positions are written into the members fNpeaks and fPositionX.
int	SearchHighRes(double[] source, double[] destVector, int ssize, double sigma, double threshold, boolean backgroundRemove, int deconIterations, boolean markov, int averWindow) ONE-DIMENSIONAL HIGH-RESOLUTION PEAK SEARCH FUNCTION This function searches for peaks in source spectrum It is based on deconvolution method.
void	SetAverageWindow(int w)
void	SetResolution(double resolution)

Methods inherited from class java.lang.Object

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

Field Detail

fgAverageWindow

protected static int fgAverageWindow

fgIterations

protected static int fgIterations

fMaxPeaks

protected int fMaxPeaks

fNPeaks

protected int fNPeaks

fPosition

protected double[] fPosition

fPositionX

protected double[] fPositionX

fPositionY

protected double[] fPositionY

fResolution

protected double fResolution

Constructor Detail

TSpectrum

public TSpectrum()

The TSpectrum() default constructor

TSpectrum

public TSpectrum(int maxpositions,
                 double resolution)

Parameters:

maxpositions - maximum number of peaks

resolution - determines resolution of the neighboring peaks default value is 1 correspond to 3 sigma distance between peaks. Higher values allow higher resolution (smaller distance between peaks. May be set later through SetResolution.)

Method Detail

finalize

public void finalize()

TSpectrum desctructor

Overrides:

finalize in class Object

getNPeaks

public int getNPeaks()

Returns:

number of peaks found

getPeakX

public double[] getPeakX()

Returns:

X coordinates of found peaks

getPeakY

public double[] getPeakY()

Returns:

Y coordinates of found peaks

Search

public int Search(double[] hinX,
                  double[] hinY,
                  double[] houtX,
                  double[] houtY,
                  double sigma,
                  String option,
                  double threshold)

ONE-DIMENSIONAL PEAK SEARCH FUNCTION This function searches for peaks in source spectrum in hin The number of found peaks and their positions are written into the members fNpeaks and fPositionX. The search is performed in the current histogram range. Function parameters:

Parameters:

hinX - histogram x of source spectrum

hinY - histogram Y of source spectrum

houtX - out histogram of source spectrum

houtY - out histogram of source spectrum

sigma - sigma of searched peaks, for details we refer to manual

option - string options passed to the algorithms

threshold - (default=0.05) peaks with amplitude less than threshold*highest_peak are discarded. 0 < threshold <1 By default, the background is removed before deconvolution. Specify the option "nobackground" to not remove the background. By default the "Markov" chain algorithm is used. Specify the option "noMarkov" to disable this algorithm Note that by default the source spectrum is replaced by a new spectrum

Returns:

number of found peaks

SearchHighRes

public int SearchHighRes(double[] source,
                         double[] destVector,
                         int ssize,
                         double sigma,
                         double threshold,
                         boolean backgroundRemove,
                         int deconIterations,
                         boolean markov,
                         int averWindow)

ONE-DIMENSIONAL HIGH-RESOLUTION PEAK SEARCH FUNCTION This function searches for peaks in source spectrum It is based on deconvolution method. First the background is removed (if desired), then Markov spectrum is calculated (if desired), then the response function is generated according to given sigma and deconvolution is carried out.

Parameters:

source - vector of source spectrum

destVector - vector of resulting deconvolved spectrum

ssize - length of source spectrum

sigma - sigma of searched peaks, for details we refer to manual

threshold - threshold value in % for selected peaks, peaks with amplitude less than threshold*highest_peak/100 are ignored, see manual

backgroundRemove - logical variable, set if the removal of background before deconvolution is desired

deconIterations - number of iterations in deconvolution operation

markov - logical variable, if it is true, first the source spectrum is replaced by new spectrum calculated using Markov chains method.

averWindow - averaging window of searched peaks, for details we refer to manual (applies only for Markov method)

Returns:

number of found peaks

SetAverageWindow

public void SetAverageWindow(int w)

Parameters:

w - average window of searched peaks

See Also:

SearchHighRes(double[], double[], int, double, double, boolean, int, boolean, int)

SetResolution

public void SetResolution(double resolution)

Parameters:

resolution - determines resolution of the neighboring peaks default value is 1 correspond to 3 sigma distance between peaks. Higher values allow higher resolution (smaller distance between peaks. May be set later through SetResolution.

main

public static void main(String[] argv)