PixtoolsHealpixSkyPixellator (Starjava Table API)

java.lang.Object
- uk.ac.starlink.table.join.HealpixSkyPixellator
- - uk.ac.starlink.table.join.PixtoolsHealpixSkyPixellator

All Implemented Interfaces:

SkyPixellator
```
public class PixtoolsHealpixSkyPixellator
extends HealpixSkyPixellator
```
HEALPix sky pixellator using the PixTools library. This implementation is based on the PixTools Java HEALPix classes written by Nickolai Kouropatkine at Fermilab. The maximum K value is 20.

Author:

Mark Taylor (Starlink), Nickolai Kouropatkine (EAG, Fermilab)

See Also:

http://home.fnal.gov/~kuropat/HEALPIX/PixTools.html

Constructor Summary

Constructors
Constructor	Description
`PixtoolsHealpixSkyPixellator()`	Constructs a pixellator using the default scheme (RING).
`PixtoolsHealpixSkyPixellator(boolean nested)`	Constructs a pixellator using either the RING or NESTED HEALPix scheme.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`calculateDefaultK(double scale)`	Determines a default value to use for the HEALPix k parameter based on a given scale.
`protected void`	`configureK(int k)`	Updates internal state for the current value of the k parameter.
`java.lang.Object[]`	`getPixels(double alpha, double delta, double radius)`	Returns an array of objects representing pixels in a given region.

Methods inherited from class uk.ac.starlink.table.join.HealpixSkyPixellator
getHealpixK, getMaxK, getScale, getTuningParameter, setHealpixK, setScale

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

- Constructor Detail
  - PixtoolsHealpixSkyPixellator
```
public PixtoolsHealpixSkyPixellator(boolean nested)
```
    Constructs a pixellator using either the RING or NESTED HEALPix scheme.
    
    Parameters:
    
    nested - false for RING scheme, true for NESTED
  - PixtoolsHealpixSkyPixellator
```
public PixtoolsHealpixSkyPixellator()
```
    Constructs a pixellator using the default scheme (RING).
- Method Detail
  - getPixels
```
public java.lang.Object[] getPixels(double alpha,
                                    double delta,
                                    double radius)
```
    Description copied from interface: SkyPixellator
    
    Returns an array of objects representing pixels in a given region. The parameters specify a small circle on the sphere; any pixels which overlap this circle must be returned (additional pixels may also be returned). The output objects are of some opaque type, but must implement the equals and hashCode methods appropriately, so that objects returned from one call can be compared for identity with objects returned from a subsequent call. This comparability is only guaranteed to work if the pixel scale is not changed in between calls.
    
    Parameters:
    
    alpha - right ascension of circle centre in radians
    
    delta - declination of circle centre in radians
    
    radius - radius of circle in radians
    
    Returns:
    
    array of opaque but comparable pixel objects
  - configureK
```
protected void configureK(int k)
```
    Description copied from class: HealpixSkyPixellator
    
    Updates internal state for the current value of the k parameter.
    
    Specified by:
    
    configureK in class HealpixSkyPixellator
    
    Parameters:
    
    k - HEALPix order
  - calculateDefaultK
```
public int calculateDefaultK(double scale)
```
    Determines a default value to use for the HEALPix k parameter based on a given scale.
    
    Specified by:
    
    calculateDefaultK in class HealpixSkyPixellator
    
    Parameters:
    
    scale - distance scale, in radians

Class PixtoolsHealpixSkyPixellator

Constructor Summary

Method Summary

Methods inherited from class uk.ac.starlink.table.join.HealpixSkyPixellator

Methods inherited from class java.lang.Object

Constructor Detail

PixtoolsHealpixSkyPixellator

PixtoolsHealpixSkyPixellator

Method Detail

getPixels

configureK

calculateDefaultK