cern.colt.matrix.tobject.impl

Class DenseObjectMatrix2D

java.lang.Object

cern.colt.PersistentObject

cern.colt.matrix.AbstractMatrix

cern.colt.matrix.AbstractMatrix2D

cern.colt.matrix.tobject.ObjectMatrix2D

cern.colt.matrix.tobject.impl.DenseObjectMatrix2D

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class DenseObjectMatrix2D
extends ObjectMatrix2D

Dense 2-d matrix holding Object elements. First see the package summary and javadoc tree view to get the broad picture.

Implementation:

Internally holds one single contigous one-dimensional array, addressed in row major. Note that this implementation is not synchronized.

Memory requirements:

memory [bytes] = 8*rows()*columns(). Thus, a 1000*1000 matrix uses 8 MB.

Time complexity:

O(1) (i.e. constant time) for the basic operations get, getQuick, set, setQuick and size,

Cells are internally addressed in row-major. Applications demanding utmost speed can exploit this fact. Setting/getting values in a loop row-by-row is quicker than column-by-column. Thus

 for (int row = 0; row < rows; row++) {
     for (int column = 0; column < columns; column++) {
         matrix.setQuick(row, column, someValue);
     }
 }
 

is quicker than

 for (int column = 0; column < columns; column++) {
     for (int row = 0; row < rows; row++) {
         matrix.setQuick(row, column, someValue);
     }
 }
 

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
DenseObjectMatrix2D(int rows, int columns) Constructs a matrix with a given number of rows and columns.
DenseObjectMatrix2D(java.lang.Object[][] values) Constructs a matrix with a copy of the given values.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	aggregate(ObjectMatrix2D other, ObjectObjectFunction aggr, ObjectObjectFunction f) Applies a function to each corresponding cell of two matrices and aggregates the results.
java.lang.Object	aggregate(ObjectObjectFunction aggr, ObjectFunction f) Applies a function to each cell and aggregates the results.
java.lang.Object	aggregate(ObjectObjectFunction aggr, ObjectFunction f, IntArrayList rowList, IntArrayList columnList) Applies a function to all cells with a given indexes and aggregates the results.
java.lang.Object	aggregate(ObjectObjectFunction aggr, ObjectFunction f, ObjectProcedure cond) Applies a function to each cell that satisfies a condition and aggregates the results.
ObjectMatrix2D	assign(java.lang.Object value) Sets all cells to the state specified by value.
ObjectMatrix2D	assign(java.lang.Object[] values) Sets all cells to the state specified by values.
ObjectMatrix2D	assign(java.lang.Object[][] values) Sets all cells to the state specified by values.
ObjectMatrix2D	assign(ObjectFunction function) Assigns the result of a function to each cell; x[row,col] = function(x[row,col]).
ObjectMatrix2D	assign(ObjectMatrix2D source) Replaces all cell values of the receiver with the values of another matrix.
ObjectMatrix2D	assign(ObjectMatrix2D y, ObjectObjectFunction function) Assigns the result of a function to each cell; x[row,col] = function(x[row,col],y[row,col]).
ObjectMatrix2D	assign(ObjectMatrix2D y, ObjectObjectFunction function, IntArrayList rowList, IntArrayList columnList) Assigns the result of a function to all cells with a given indexes
ObjectMatrix2D	assign(ObjectProcedure cond, java.lang.Object value) Assigns a value to all cells that satisfy a condition.
ObjectMatrix2D	assign(ObjectProcedure cond, ObjectFunction function) Assigns the result of a function to all cells that satisfy a condition.
java.lang.Object[]	elements() Returns the elements of this matrix.
java.lang.Object	getQuick(int row, int column) Returns the matrix cell value at coordinate [row,column].
long	index(int row, int column) Returns the position of the given coordinate within the (virtual or non-virtual) internal 1-dimensional array.
ObjectMatrix2D	like(int rows, int columns) Construct and returns a new empty matrix of the same dynamic type as the receiver, having the specified number of rows and columns.
ObjectMatrix1D	like1D(int size) Construct and returns a new 1-d matrix of the corresponding dynamic type, entirelly independent of the receiver.
void	setQuick(int row, int column, java.lang.Object value) Sets the matrix cell at coordinate [row,column] to the specified value.
ObjectMatrix1D	vectorize() Returns a vector obtained by stacking the columns of the matrix on top of one another.

Methods inherited from class cern.colt.matrix.tobject.ObjectMatrix2D

cardinality, copy, equals, equals, forEachNonZero, get, getNonZeros, like, set, toArray, toString, viewColumn, viewColumnFlip, viewDice, viewPart, viewRow, viewRowFlip, viewSelection, viewSelection, viewSorted, viewStrides

Methods inherited from class cern.colt.matrix.AbstractMatrix2D

checkShape, checkShape, columns, columnStride, rows, rowStride, size, toStringShort

Methods inherited from class cern.colt.matrix.AbstractMatrix

ensureCapacity, isView, trimToSize

Methods inherited from class cern.colt.PersistentObject

clone

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

DenseObjectMatrix2D

public DenseObjectMatrix2D(java.lang.Object[][] values)

Constructs a matrix with a copy of the given values. values is required to have the form values[row][column] and have exactly the same number of columns in every row.

The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.

Parameters:

values - The values to be filled into the new matrix.

Throws:

java.lang.IllegalArgumentException - if for any 1 <= row < values.length: values[row].length != values[row-1].length .

DenseObjectMatrix2D

public DenseObjectMatrix2D(int rows,
                           int columns)

Constructs a matrix with a given number of rows and columns. All entries are initially 0.

Parameters:

rows - the number of rows the matrix shall have.

columns - the number of columns the matrix shall have.

Throws:

java.lang.IllegalArgumentException - if rows<0 || columns<0 || (double)columns*rows > Integer.MAX_VALUE .

Method Detail

aggregate

public java.lang.Object aggregate(ObjectObjectFunction aggr,
                                  ObjectFunction f)

Description copied from class: ObjectMatrix2D

Applies a function to each cell and aggregates the results. Returns a value v such that v==a(size()) where a(i) == aggr( a(i-1), f(get(row,column)) ) and terminators are a(1) == f(get(0,0)), a(0)==null.

Example:

         cern.jet.math.Functions F = cern.jet.math.Functions.functions;
         2 x 2 matrix
         0 1
         2 3
 
         // Sum( x[row,col]*x[row,col] ) 
         matrix.aggregate(F.plus,F.square);
         --> 14
 
 

For further examples, see the package doc.

Overrides:

aggregate in class ObjectMatrix2D

Parameters:

aggr - an aggregation function taking as first argument the current aggregation and as second argument the transformed current cell value.

f - a function transforming the current cell value.

Returns:

the aggregated measure.

See Also:

DoubleFunctions

aggregate

public java.lang.Object aggregate(ObjectObjectFunction aggr,
                                  ObjectFunction f,
                                  ObjectProcedure cond)

Description copied from class: ObjectMatrix2D

Applies a function to each cell that satisfies a condition and aggregates the results.

Overrides:

aggregate in class ObjectMatrix2D

Parameters:

aggr - an aggregation function taking as first argument the current aggregation and as second argument the transformed current cell value.

f - a function transforming the current cell value.

cond - a condition.

Returns:

the aggregated measure.

aggregate

public java.lang.Object aggregate(ObjectObjectFunction aggr,
                                  ObjectFunction f,
                                  IntArrayList rowList,
                                  IntArrayList columnList)

Description copied from class: ObjectMatrix2D

Applies a function to all cells with a given indexes and aggregates the results.

Overrides:

aggregate in class ObjectMatrix2D

Parameters:

aggr - an aggregation function taking as first argument the current aggregation and as second argument the transformed current cell value.

f - a function transforming the current cell value.

rowList - row indexes.

columnList - column indexes.

Returns:

the aggregated measure.

aggregate

public java.lang.Object aggregate(ObjectMatrix2D other,
                                  ObjectObjectFunction aggr,
                                  ObjectObjectFunction f)

Description copied from class: ObjectMatrix2D

Applies a function to each corresponding cell of two matrices and aggregates the results. Returns a value v such that v==a(size()) where a(i) == aggr( a(i-1), f(get(row,column),other.get(row,column)) ) and terminators are a(1) == f(get(0,0),other.get(0,0)), a(0)==null.

Example:

         cern.jet.math.Functions F = cern.jet.math.Functions.functions;
         x == 2 x 2 matrix
         0 1
         2 3
 
         y == 2 x 2 matrix
         0 1
         2 3
 
         // Sum( x[row,col] * y[row,col] ) 
         x.aggregate(y, F.plus, F.mult);
         --> 14
 
         // Sum( (x[row,col] + y[row,col])ˆ2 )
         x.aggregate(y, F.plus, F.chain(F.square,F.plus));
         --> 56
 
 

For further examples, see the package doc.

Overrides:

aggregate in class ObjectMatrix2D

aggr - an aggregation function taking as first argument the current aggregation and as second argument the transformed current cell values.

f - a function transforming the current cell values.

Returns:

the aggregated measure.

See Also:

DoubleFunctions

assign

public ObjectMatrix2D assign(java.lang.Object value)

Description copied from class: ObjectMatrix2D

Sets all cells to the state specified by value.

Overrides:

assign in class ObjectMatrix2D

Parameters:

value - the value to be filled into the cells.

Returns:

this (for convenience only).

assign

public ObjectMatrix2D assign(java.lang.Object[][] values)

Sets all cells to the state specified by values. values is required to have the form values[row][column] and have exactly the same number of rows and columns as the receiver.

The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.

Overrides:

assign in class ObjectMatrix2D

Parameters:

values - the values to be filled into the cells.

Returns:

this (for convenience only).

Throws:

java.lang.IllegalArgumentException - if values.length != rows() || for any 0 <= row < rows(): values[row].length != columns() .

assign

public ObjectMatrix2D assign(ObjectFunction function)

Assigns the result of a function to each cell; x[row,col] = function(x[row,col]).

Example:

         matrix = 2 x 2 matrix
         0.5 1.5      
         2.5 3.5
 
         // change each cell to its sine
         matrix.assign(cern.jet.math.Functions.sin);
         -->
         2 x 2 matrix
         0.479426  0.997495 
         0.598472 -0.350783
 
 

For further examples, see the package doc.

Overrides:

assign in class ObjectMatrix2D

Parameters:

function - a function object taking as argument the current cell's value.

Returns:

this (for convenience only).

See Also:

DoubleFunctions

assign

public ObjectMatrix2D assign(ObjectProcedure cond,
                             ObjectFunction function)

Description copied from class: ObjectMatrix2D

Assigns the result of a function to all cells that satisfy a condition.

Overrides:

assign in class ObjectMatrix2D

Parameters:

cond - a condition.

function - a function object.

Returns:

this (for convenience only).

assign

public ObjectMatrix2D assign(ObjectProcedure cond,
                             java.lang.Object value)

Description copied from class: ObjectMatrix2D

Assigns a value to all cells that satisfy a condition.

Overrides:

assign in class ObjectMatrix2D

Parameters:

cond - a condition.

value - a value.

Returns:

this (for convenience only).

assign

public ObjectMatrix2D assign(ObjectMatrix2D source)

Replaces all cell values of the receiver with the values of another matrix. Both matrices must have the same number of rows and columns. If both matrices share the same cells (as is the case if they are views derived from the same matrix) and intersect in an ambiguous way, then replaces as if using an intermediate auxiliary deep copy of other.

Overrides:

assign in class ObjectMatrix2D

Parameters:

source - the source matrix to copy from (may be identical to the receiver).

Returns:

this (for convenience only).

Throws:

java.lang.IllegalArgumentException - if columns() != source.columns() || rows() != source.rows()

assign

public ObjectMatrix2D assign(ObjectMatrix2D y,
                             ObjectObjectFunction function)

Assigns the result of a function to each cell; x[row,col] = function(x[row,col],y[row,col]).

Overrides:

assign in class ObjectMatrix2D

Parameters:

y - the secondary matrix to operate on.

function - a function object taking as first argument the current cell's value of this, and as second argument the current cell's value of y,

Returns:

this (for convenience only).

Throws:

java.lang.IllegalArgumentException - if columns() != other.columns() || rows() != other.rows()

See Also:

DoubleFunctions

assign

public ObjectMatrix2D assign(java.lang.Object[] values)

Description copied from class: ObjectMatrix2D

Sets all cells to the state specified by values. values is required to have the form values[row*column] and elements have to be stored in a row-wise order.

The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.

Overrides:

assign in class ObjectMatrix2D

Parameters:

values - the values to be filled into the cells.

Returns:

this (for convenience only).

assign

public ObjectMatrix2D assign(ObjectMatrix2D y,
                             ObjectObjectFunction function,
                             IntArrayList rowList,
                             IntArrayList columnList)

Description copied from class: ObjectMatrix2D

Assigns the result of a function to all cells with a given indexes

Overrides:

assign in class ObjectMatrix2D

Parameters:

y - the secondary matrix to operate on.

function - a function object taking as first argument the current cell's value of this, and as second argument the current cell's value of y,

rowList - row indexes.

columnList - column indexes.

Returns:

this (for convenience only).

elements

public java.lang.Object[] elements()

Description copied from class: ObjectMatrix2D

Returns the elements of this matrix.

Specified by:

elements in class ObjectMatrix2D

Returns:

the elements

getQuick

public java.lang.Object getQuick(int row,
                                 int column)

Returns the matrix cell value at coordinate [row,column].

Provided with invalid parameters this method may return invalid objects without throwing any exception. You should only use this method when you are absolutely sure that the coordinate is within bounds. Precondition (unchecked): 0 <= column < columns() && 0 <= row < rows().

Specified by:

getQuick in class ObjectMatrix2D

Parameters:

row - the index of the row-coordinate.

column - the index of the column-coordinate.

Returns:

the value at the specified coordinate.

index

public long index(int row,
                  int column)

Returns the position of the given coordinate within the (virtual or non-virtual) internal 1-dimensional array.

Overrides:

index in class AbstractMatrix2D

Parameters:

row - the index of the row-coordinate.

column - the index of the column-coordinate.

like

public ObjectMatrix2D like(int rows,
                           int columns)

Construct and returns a new empty matrix of the same dynamic type as the receiver, having the specified number of rows and columns. For example, if the receiver is an instance of type DenseObjectMatrix2D the new matrix must also be of type DenseObjectMatrix2D, if the receiver is an instance of type SparseObjectMatrix2D the new matrix must also be of type SparseObjectMatrix2D, etc. In general, the new matrix should have internal parametrization as similar as possible.

Specified by:

like in class ObjectMatrix2D

Parameters:

rows - the number of rows the matrix shall have.

columns - the number of columns the matrix shall have.

Returns:

a new empty matrix of the same dynamic type.

like1D

public ObjectMatrix1D like1D(int size)

Construct and returns a new 1-d matrix of the corresponding dynamic type, entirelly independent of the receiver. For example, if the receiver is an instance of type DenseObjectMatrix2D the new matrix must be of type DenseObjectMatrix1D, if the receiver is an instance of type SparseObjectMatrix2D the new matrix must be of type SparseObjectMatrix1D, etc.

Specified by:

like1D in class ObjectMatrix2D

Parameters:

size - the number of cells the matrix shall have.

Returns:

a new matrix of the corresponding dynamic type.

setQuick

public void setQuick(int row,
                     int column,
                     java.lang.Object value)

Sets the matrix cell at coordinate [row,column] to the specified value.

Provided with invalid parameters this method may access illegal indexes without throwing any exception. You should only use this method when you are absolutely sure that the coordinate is within bounds. Precondition (unchecked): 0 <= column < columns() && 0 <= row < rows().

Specified by:

setQuick in class ObjectMatrix2D

Parameters:

row - the index of the row-coordinate.

column - the index of the column-coordinate.

value - the value to be filled into the specified cell.

vectorize

public ObjectMatrix1D vectorize()

Description copied from class: ObjectMatrix2D

Returns a vector obtained by stacking the columns of the matrix on top of one another.

Specified by:

vectorize in class ObjectMatrix2D

Returns:

a vector of columns of this matrix.