edu.stanford.math.plex

Class MappedBufferData

java.lang.Object

edu.stanford.math.plex.PointData

edu.stanford.math.plex.PointData.NSpace

edu.stanford.math.plex.MappedBufferData

public class MappedBufferData
extends PointData.NSpace

The MappedBufferData class is another very simple implementation of NSpace. Intended for larger, but still mappable, data sets.

Version:

$Id$

Nested Class Summary

Nested classes/interfaces inherited from class edu.stanford.math.plex.PointData

PointData.Discrete, PointData.NSpace, PointData.Predicate

Field Summary

Fields inherited from class edu.stanford.math.plex.PointData

rand

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	MappedBufferData()
	MappedBufferData(java.lang.String filename)
	MappedBufferData(java.lang.String filename, boolean writable)
	MappedBufferData(java.lang.String filename, int start_dimension)
	MappedBufferData(java.lang.String filename, int start_dimension, int stop_dimension, boolean writable)
	MappedBufferData(java.lang.String filename, int num_pts, int dimension, double min, double max)
	MappedBufferData(java.lang.String filename, int num_pts, int dimension, int partition_count)
	MappedBufferData(java.lang.String filename, int length, int dimension, int start_dimension, int stop_dimension)

Method Summary

Methods

Modifier and Type	Method and Description
protected boolean	buf_is_consistent(java.nio.DoubleBuffer buf, int dimension, boolean just_created)
double	coordinate(int p, int i) Get coordinates.
int	count() The number of data points.
static void	delete(java.lang.String filename)
int	dimension() The number of dimensions of the space.
double	distance(int p1, int p2) Euclidean distance.
protected static java.nio.MappedByteBuffer	empty_dbl_file(java.lang.String filename, int len)
protected static boolean	file_exists(java.lang.String filename, boolean andWriteable)
void	force() Force changes to data back to file.
double[]	get_pt(int p, double[] vec) Get point.
protected static void	make_empty_file(java.lang.String filename, int bytes)
protected static java.nio.MappedByteBuffer	map_file(java.lang.String filename, boolean writable)
double	set_coordinate(int p, int i, double v) Set coordinates.
double[]	set_pt(int p, double[] vec) Set point.
int	start() The first data dimension of the space.
int	stop() The last data dimension of the space.

Methods inherited from class edu.stanford.math.plex.PointData.NSpace

xi

Methods inherited from class edu.stanford.math.plex.PointData

random_points

Methods inherited from class java.lang.Object

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

Constructor Detail

MappedBufferData

protected MappedBufferData()

MappedBufferData

public MappedBufferData(java.lang.String filename,
                int length,
                int dimension,
                int start_dimension,
                int stop_dimension)

MappedBufferData

public MappedBufferData(java.lang.String filename,
                int start_dimension,
                int stop_dimension,
                boolean writable)

MappedBufferData

public MappedBufferData(java.lang.String filename)

MappedBufferData

public MappedBufferData(java.lang.String filename,
                boolean writable)

MappedBufferData

public MappedBufferData(java.lang.String filename,
                int start_dimension)

MappedBufferData

public MappedBufferData(java.lang.String filename,
                int num_pts,
                int dimension,
                double min,
                double max)

MappedBufferData

public MappedBufferData(java.lang.String filename,
                int num_pts,
                int dimension,
                int partition_count)

Method Detail

dimension

public int dimension()

The number of dimensions of the space.

Specified by:

dimension in class PointData.NSpace

Returns:

the dimension of the data.

start

public int start()

The first data dimension of the space.

Returns:

the first data dimension of the space.

stop

public int stop()

The last data dimension of the space.

Returns:

the last data dimension of the space.

count

public int count()

The number of data points.

Specified by:

count in class PointData

Returns:

the number of points

distance

public double distance(int p1,
              int p2)

Euclidean distance.

Specified by:

distance in class PointData

Parameters:

p1 - the first point

p2 - the second point

Returns:

the Euclidean distance between p1 and p2.

get_pt

public double[] get_pt(int p,
              double[] vec)

Get point. No checking.

Parameters:

p - the point

vec - place to store point

Returns:

Coordinates of p;

set_pt

public double[] set_pt(int p,
              double[] vec)

Set point. No checking. Just for testing.

Parameters:

p - the point

vec - the coordinate values

Returns:

The coordinates of p.

coordinate

public double coordinate(int p,
                int i)

Get coordinates. Not much checking.

Specified by:

coordinate in class PointData.NSpace

Parameters:

p - the point

i - the coordinate

Returns:

The i-th coordinate of p;

set_coordinate

public double set_coordinate(int p,
                    int i,
                    double v)

Set coordinates. No checking.

Parameters:

p - the point

i - the coordinate

v - the coordinate value

Returns:

The i-th coordinate of p;

force

public void force()

Force changes to data back to file.

file_exists

protected static boolean file_exists(java.lang.String filename,
                  boolean andWriteable)

delete

public static void delete(java.lang.String filename)

make_empty_file

protected static void make_empty_file(java.lang.String filename,
                   int bytes)

empty_dbl_file

protected static java.nio.MappedByteBuffer empty_dbl_file(java.lang.String filename,
                                       int len)

map_file

protected static java.nio.MappedByteBuffer map_file(java.lang.String filename,
                                 boolean writable)

buf_is_consistent

protected boolean buf_is_consistent(java.nio.DoubleBuffer buf,
                        int dimension,
                        boolean just_created)