edu.jhu.pha.sdss.fits
Class Histogram

java.lang.Object
  edu.jhu.pha.sdss.fits.Histogram

public class Histogram

extends java.lang.Object

   Current Version
   ===============
   ID:            $Id: Histogram.html,v 1.1 2004/07/23 22:04:49 carliles Exp $
   Revision:      $Revision: 1.1 $
   Date/time:     $Date: 2004/07/23 22:04:49 $
   

Nested Class Summary

static class

Histogram.Bounds A container class used by the calculateBounds method.

Constructor Summary

Histogram(double min, double max, int totalCount, int[] counts)

Method Summary

Histogram.Bounds	calculateBounds(double percentKept)
double	estimateSigma()
int[]	getCounts()
int	getEqualizedValue(int val)
double	getMax()
double	getMin()
double	getRange()
int	getTotalCount()
static java.lang.String	revision()

Methods inherited from class java.lang.Object

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

Constructor Detail

Histogram

public Histogram(double min,
                 double max,
                 int totalCount,
                 int[] counts)

Method Detail

getMin

public double getMin()

getMax

public double getMax()

getRange

public double getRange()

getTotalCount

public int getTotalCount()

getCounts

public int[] getCounts()

getEqualizedValue

public int getEqualizedValue(int val)

Returns:

A histogram equalized value for val. val must be in the range [0, 65535], and is interpreted to be a linear scaling of an original data value.

estimateSigma

public double estimateSigma()

Returns:

A reasonable guess at a good sigma value for the inverse hyperbolic sine scaling. The estimate is made by finding the mode value of the histogram, then moving to the next bin and returning the value (in the original data range with bZero and bScale applied) at the "bottom" of that bin. The current implementation is actually a mangled implementation which happens to produce better sigmas than the correct implementation. An explanation for this behavior is currently being investigated.

calculateBounds

public Histogram.Bounds calculateBounds(double percentKept)
                                 throws java.lang.IllegalArgumentException

Returns:

An instance of Bounds containing the min and max values that will result in keeping percentKept percent of the values in the image. percentKept is a slightly deceptive name, as it must be in the range [0, 1].

Throws:

java.lang.IllegalArgumentException

revision

public static java.lang.String revision()

Returns:

CVS Revision number.