Package org.ejml.data

Class DMatrixD1

java.lang.Object

org.ejml.data.DMatrixD1

All Implemented Interfaces:

java.io.Serializable, DMatrix, Matrix, ReshapeMatrix

Direct Known Subclasses:

DMatrix1Row, DMatrixRBlock

public abstract class DMatrixD1
extends java.lang.Object
implements ReshapeMatrix, DMatrix

A generic abstract class for matrices whose data is stored in a single 1D array of doubles. The format of the elements in this array is not specified. For example row major, column major, and block row major are all common formats.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
double[]	data	Where the raw data for the matrix is stored.
int	numCols	Number of columns in the matrix.
int	numRows	Number of rows in the matrix.

Constructor Summary

Constructors

Constructor	Description
DMatrixD1()

Method Summary

Modifier and Type	Method	Description
double	div(int index, double val)	Divides the specified value to the internal data array at the specified index. Equivalent to: this.data[index] /= val;
double	get(int index)	Returns the value of the matrix at the specified internal array index.
double[]	getData()	Used to get a reference to the internal data.
abstract int	getIndex(int row, int col)	Returns the internal array index for the specified row and column.
int	getNumCols()	Returns the number of columns in this matrix.
int	getNumRows()	Returns the number of rows in this matrix.
DMatrixIterator	iterator(boolean rowMajor, int minRow, int minCol, int maxRow, int maxCol)	Creates a new iterator for traversing through a submatrix inside this matrix.
double	minus(int index, double val)	Subtracts the specified value to the internal data array at the specified index. Equivalent to: this.data[index] -= val;
double	plus(int index, double val)	Adds the specified value to the internal data array at the specified index. Equivalent to: this.data[index] += val;
void	print()	Prints the matrix to standard out using standard formatting.
void	print(java.lang.String format)	Prints the matrix to standard out with the specified formatting.
void	reshape(int numRows, int numCols)	Equivalent to invoking reshape(numRows,numCols,false);
abstract void	reshape(int numRows, int numCols, boolean saveValues)	Changes the number of rows and columns in the matrix, allowing its size to grow or shrink.
double	set(int index, double val)	Sets the element's value at the specified index.
void	set(DMatrixD1 b)	Sets the value of this matrix to be the same as the value of the provided matrix.
void	setData(double[] data)	Changes the internal array reference.
void	setNumCols(int numCols)	Sets the number of columns.
void	setNumRows(int numRows)	Sets the number of rows.
double	times(int index, double val)	Multiplies the specified value to the internal data array at the specified index. Equivalent to: this.data[index] *= val;

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.ejml.data.DMatrix

get, getNumElements, set, unsafe_get, unsafe_set

Methods inherited from interface org.ejml.data.Matrix

copy, create, createLike, getType, set, zero

Field Detail

data

public double[] data

Where the raw data for the matrix is stored. The format is type dependent.

numRows

public int numRows

Number of rows in the matrix.

numCols

public int numCols

Number of columns in the matrix.

Constructor Detail

DMatrixD1

public DMatrixD1()

Method Detail

getData

public double[] getData()

Used to get a reference to the internal data.

Returns:

Reference to the matrix's data.

setData

public void setData(double[] data)

Changes the internal array reference.

getIndex

public abstract int getIndex(int row,
                             int col)

Returns the internal array index for the specified row and column.

Parameters:

row - Row index.

col - Column index.

Returns:

Internal array index.

set

public void set(DMatrixD1 b)

Sets the value of this matrix to be the same as the value of the provided matrix. Both matrices must have the same shape:

a_ij = b_ij

Parameters:

b - The matrix that this matrix is to be set equal to.

get

public double get(int index)

Returns the value of the matrix at the specified internal array index. The element at which row and column returned by this function depends upon the matrix's internal structure, e.g. row-major, column-major, or block.

Parameters:

index - Internal array index.

Returns:

Value at the specified index.

set

public double set(int index,
                  double val)

Sets the element's value at the specified index. The element at which row and column modified by this function depends upon the matrix's internal structure, e.g. row-major, column-major, or block.

Parameters:

index - Index of element that is to be set.

val - The new value of the index.

plus

public double plus(int index,
                   double val)

Adds the specified value to the internal data array at the specified index.

Equivalent to: this.data[index] += val;

Intended for use in highly optimized code. The row/column coordinate of the modified element is dependent upon the matrix's internal structure.

Parameters:

index - The index which is being modified.

val - The value that is being added.

minus

public double minus(int index,
                    double val)

Subtracts the specified value to the internal data array at the specified index.

Equivalent to: this.data[index] -= val;

Intended for use in highly optimized code. The row/column coordinate of the modified element is dependent upon the matrix's internal structure.

Parameters:

index - The index which is being modified.

val - The value that is being subtracted.

times

public double times(int index,
                    double val)

Multiplies the specified value to the internal data array at the specified index.

Equivalent to: this.data[index] *= val;

Intended for use in highly optimized code. The row/column coordinate of the modified element is dependent upon the matrix's internal structure.

Parameters:

index - The index which is being modified.

val - The value that is being multiplied.

div

public double div(int index,
                  double val)

Divides the specified value to the internal data array at the specified index.

Equivalent to: this.data[index] /= val;

Intended for use in highly optimized code. The row/column coordinate of the modified element is dependent upon the matrix's internal structure.

Parameters:

index - The index which is being modified.

val - The value that is being divided.

reshape

public abstract void reshape(int numRows,
                             int numCols,
                             boolean saveValues)

Changes the number of rows and columns in the matrix, allowing its size to grow or shrink. If the saveValues flag is set to true, then the previous values will be maintained, but reassigned to new elements in a row-major ordering. If saveValues is false values will only be maintained when the requested size is less than or equal to the internal array size. The primary use for this function is to encourage data reuse and avoid unnecessarily declaring and initialization of new memory.

Examples:
[ 1 2 ; 3 4 ] → reshape( 2 , 3 , true ) = [ 1 2 3 ; 4 0 0 ]
[ 1 2 ; 3 4 ] → reshape( 1 , 2 , true ) = [ 1 2 ]
[ 1 2 ; 3 4 ] → reshape( 1 , 2 , false ) = [ 1 2 ]
[ 1 2 ; 3 4 ] → reshape( 2 , 3 , false ) = [ 0 0 0 ; 0 0 0 ]

Parameters:

numRows - The new number of rows in the matrix.

numCols - The new number of columns in the matrix.

saveValues - If true then the value of each element will be save using a row-major reordering. Typically this should be false.

reshape

public void reshape(int numRows,
                    int numCols)

Equivalent to invoking reshape(numRows,numCols,false);

Specified by:

reshape in interface ReshapeMatrix

Parameters:

numRows - The new number of rows in the matrix.

numCols - The new number of columns in the matrix.

iterator

public DMatrixIterator iterator(boolean rowMajor,
                                int minRow,
                                int minCol,
                                int maxRow,
                                int maxCol)

Creates a new iterator for traversing through a submatrix inside this matrix. It can be traversed by row or by column. Range of elements is inclusive, e.g. minRow = 0 and maxRow = 1 will include rows 0 and 1. The iteration starts at (minRow,minCol) and ends at (maxRow,maxCol)

Parameters:

rowMajor - true means it will traverse through the submatrix by row first, false by columns.

minRow - first row it will start at.

minCol - first column it will start at.

maxRow - last row it will stop at.

maxCol - last column it will stop at.

Returns:

A new MatrixIterator

print

public void print()

Description copied from interface: Matrix

Prints the matrix to standard out using standard formatting. This is the same as calling print("%e")

Specified by:

print in interface Matrix

print

public void print(java.lang.String format)

Description copied from interface: Matrix

Prints the matrix to standard out with the specified formatting.

Specified by:

print in interface Matrix

Parameters:

format - printf style formatting for a float. E.g. "%f"

See Also:

Formatter

getNumRows

public int getNumRows()

Returns the number of rows in this matrix.

Specified by:

getNumRows in interface Matrix

Returns:

Number of rows.

getNumCols

public int getNumCols()

Returns the number of columns in this matrix.

Specified by:

getNumCols in interface Matrix

Returns:

Number of columns.

setNumRows

public void setNumRows(int numRows)

Sets the number of rows.

Parameters:

numRows - Number of rows

setNumCols

public void setNumCols(int numCols)

Sets the number of columns.

Parameters:

numCols - Number of columns