|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object | +--EDU.gatech.cc.is.learning.FunctionApproximator | +--EDU.gatech.cc.is.learning.Bilinear2D
Transform points from a two-dimensional space to another two dimensional space.
Introduction
The Bilinear2D is a vectorial function that transforms points from a
two-dimensional space to another two-dimensional space. The transformation
is specified using a grid at the domain space and associating the points at
the target space that correspond to each node of the grid.
Computation
The evaluation of query points is performed using a bilinear interpolation
of the target points associated with the four neighboring points
to the query point.
The domain space is specified by a rectangle and a grid of points.
The rectangle is defined using four numbers: min_x_limit
,
max_x_limit
, min_y_limit
, and
max_y_limit
.
The grid of points is defined using the number of points along the x and
y axes: npoints_x
and npoints_y
, and a
bidimensional array of 2D doubles (i.e., the points in the range space).
File format
A text file can be used to define a Bilinear2D function. The format is as
follows:
min_x_limit: [value] max_x_limit: [value] min_y_limit: [value] max_y_limit: [value] npoints_x: [r] npoints_y: [s] [x_00],[y_00] [x_01],[y_01] ... [x_0r],[y_0r] [x_10],[y_10] [x_11],[y_11] ... [x_1r],[y_1r] . . . . . . . . . [x_s0],[y_s0] [x_s1],[y_s1] ... [x_sr],[y_sr]Example:
min_x_limit: 0 max_x_limit: 50 min_y_limit: 0 max_y_limit: 50 npoints_x: 5 npoints_y: 5 10,20 7.5,20 5,20 2.5,20 0,20 10,15 7.5,15 5,15 2.5,15 0,15 10,10 7.5,10 5,10 2.5,10 0,10 10, 5 7.5, 5 5, 5 2.5, 5 0, 5 10, 0 7.5, 0 5, 0 2.5, 0 0, 0
Copyright (c)1997 Georgia Tech Research Corporation
FunctionApproximator
, Serialized FormField Summary | |
double |
max_x_limit
Maximum value for the x variable in the domain space. |
double |
max_y_limit
Maximum value for the y variable in the domain space. |
double |
min_x_limit
Minimum value for the x variable in the domain space. |
double |
min_y_limit
Minimum value for the y variable in the domain space. |
int |
npoints_x
Number of grid points in the x axis. |
int |
npoints_y
Number of grid points in the y axis. |
double |
range_x
Range of the x variable in the domain space: (max_limit - min_limit). |
double |
range_y
Range of the y variable in the domain space: (max_limit - min_limit). |
double |
resolution_x
Resolution of the x axis: (max_limit - min_limit) / (npoints - 1) |
double |
resolution_y
Resolution of the y axis: (max_limit - min_limit) / (npoints - 1) |
protected double[][][] |
table
Grid of points. |
Fields inherited from class EDU.gatech.cc.is.learning.FunctionApproximator |
domain_dim,
range_dim |
Constructor Summary | |
Bilinear2D(double min_x_limit,
double max_x_limit,
int npoints_x,
double min_y_limit,
double max_y_limit,
int npoints_y,
double[][][] table)
Create an instance of a Bilinear function approximator that maps points from a two-dimensional space (x,y) to another two-dimensional space (u,v). |
|
Bilinear2D(java.lang.String filename)
Loads the definition of a Bilinear2D function approximator from a file. |
Method Summary | |
double[] |
query(double[] point)
Computes and returns the bilinear interpolation associated with the point. |
double[] |
query(int x,
int y)
Computes and returns the bilinear interpolation associated with the point. |
void |
saveDefinition(java.lang.String filename)
Save a definition of this instance in a file. |
void |
update(double[] q,
double[] p)
Not implemented. |
Methods inherited from class java.lang.Object |
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait |
Field Detail |
public final double max_x_limit
public final double min_x_limit
public final double range_x
public final int npoints_x
public final double resolution_x
public final double max_y_limit
public final double min_y_limit
public final double range_y
public final int npoints_y
public final double resolution_y
protected double[][][] table
Constructor Detail |
public Bilinear2D(double min_x_limit, double max_x_limit, int npoints_x, double min_y_limit, double max_y_limit, int npoints_y, double[][][] table)
public Bilinear2D(java.lang.String filename) throws FunctionApproximatorException, java.io.IOException
filename
- the file name.FunctionApproximator
Method Detail |
public void saveDefinition(java.lang.String filename) throws FunctionApproximatorException, java.io.IOException
filename
- the file name.public double[] query(double[] point)
point
- the input point (two-dimensional array of doubles).public double[] query(int x, int y)
x
- the x ordinate of the input point.y
- the y ordinate of the input point.public void update(double[] q, double[] p) throws FunctionApproximatorException
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |