ru.sscc.spline.mesh
Class SimpleMesh

java.lang.Object
  |
  +--ru.sscc.spline.mesh.SimpleMesh

Direct Known Subclasses:

NonuniformMesh, StrictNonuniformMesh, UniformMesh

public abstract class SimpleMesh

extends java.lang.Object

implements java.io.Serializable

The description of the simple 1D mesh. The user's mesh nodes are usually affain transformed while construction of an internal mesh by the formula x'=(x-x0)*s, where x0 is a new origin point (usually the first point in the mesh) and s is a scale factor. The class provides testing of a point to find a mesh cell it belongs to.

See Also:

Serialized Form

Field Summary

protected double	origin An affine transform origin.
protected double	scale An affine fransform scaling factor.
int	size A number of mesh nodes.

Constructor Summary

protected

SimpleMesh(int size) Constructor: sets the mesh size attribute.

Method Summary

abstract double	averageStep() Returns an average mesh step.
abstract double	distance(int i, int j) Returns a distance between i-th and j-th nodes of transformed mesh, e.g.
double	extendedMeshDistance(int i, int j) Returns a distance between i-th and j-th nodes of the extended mesh.
abstract void	findCell(SimpleMeshWorkspace workspace, double x) Finds a mesh cell to which a point belongs.
static void	findCell(SimpleMeshWorkspace workspace, double t, double[] nodes, int firstIndex, int lastIndex) Finds a mesh cell to which a point belongs.
static void	findCell(SimpleMeshWorkspace workspace, double t, float[] nodes, int firstIndex, int lastIndex) Finds a mesh cell to which a point belongs.
abstract double	get(int i) Returns a value of i-th mesh node in the original coordinate system.
abstract boolean	isUniform() Returns a mesh uniformness tag.
double	origin() Returns the new origin point.
double	scale() Returns the scale factor.

Methods inherited from class java.lang.Object

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

Field Detail

size

public final int size

A number of mesh nodes.

origin

protected double origin

An affine transform origin.

scale

protected double scale

An affine fransform scaling factor.

Constructor Detail

SimpleMesh

protected SimpleMesh(int size)

Constructor: sets the mesh size attribute.

Method Detail

origin

public final double origin()

Returns the new origin point.

scale

public final double scale()

Returns the scale factor.

averageStep

public abstract double averageStep()

Returns an average mesh step.

findCell

public abstract void findCell(SimpleMeshWorkspace workspace,
                              double x)

Finds a mesh cell to which a point belongs. Writes the cell index and a position within the cell (a distance in new coordinates from the left cell bound) into workspace's attributes cellIndex and cellPoint.

Parameters:

workspace - a mesh workspace

x - a point (in original coordinates) to search

get

public abstract double get(int i)

Returns a value of i-th mesh node in the original coordinate system.

isUniform

public abstract boolean isUniform()

Returns a mesh uniformness tag.

distance

public abstract double distance(int i,
                                int j)

Returns a distance between i-th and j-th nodes of transformed mesh, e.g. the value t_i-t_j.

extendedMeshDistance

public double extendedMeshDistance(int i,
                                   int j)

Returns a distance between i-th and j-th nodes of the extended mesh. The transformed mesh is extended in both directions by a number of virtual nodes. The additional notes are usually placed with the same distance between each other. The left virtual nodes indices are -1, -2, ... and the right virtual nodes indices are size, size+1, ...

findCell

public static void findCell(SimpleMeshWorkspace workspace,
                            double t,
                            double[] nodes,
                            int firstIndex,
                            int lastIndex)

Finds a mesh cell to which a point belongs. Writes the cell index and a position within the cell (a distance in new coordinates from the left cell bound) into workspace's attributes cellIndex and cellPoint. The algorithm is adaptive (at first it tests cells neighbouring to the cell found before).

The nodes[firstIndex],...,nodes[lastIndex-1] entries are used in the algorithm. The resulting cell index is an integer value belonging to the range [firstIndex..lastIndex]. If cellIndex==firstIndex, the point is to the left from the nodes[firstIndex]. In this case, the position will be negative and equal to (t-nodes[firstIndex]). In other cases, the point position is equal to (t-nodes[cellIndex-1]).

Parameters:

workspace - the mesh workspace

t - the point (in mesh coordinates) to search

nodes - the array containing mesh nodes

firstIndex - the first index in the array to search

lastIndex - the index after the last array's entry

findCell

public static void findCell(SimpleMeshWorkspace workspace,
                            double t,
                            float[] nodes,
                            int firstIndex,
                            int lastIndex)

Finds a mesh cell to which a point belongs. Writes the cell index and a position within the cell (a distance in new coordinates from the left cell bound) into workspace's attributes cellIndex and cellPoint. The algorithm is adaptive (at first it tests cells neighbouring to the cell found before).

The nodes[firstIndex],...,nodes[lastIndex-1] entries are used in the algorithm. The resulting cell index is an integer value belonging to the range [firstIndex..lastIndex]. If cellIndex==firstIndex, the point is to the left from the nodes[firstIndex]. In this case, the position will be negative and equal to (t-nodes[firstIndex]). In other cases, the point position is equal to (t-nodes[cellIndex-1]).

Parameters:

workspace - the mesh workspace

t - the point (in mesh coordinates) to search

nodes - the array containing mesh nodes

firstIndex - the first index in the array to search

lastIndex - the index after the last array's entry