org.tribuo.math.la

Interface Matrix

All Superinterfaces:

Iterable<MatrixTuple>, Serializable, Tensor

All Known Implementing Classes:

DenseMatrix, DenseSparseMatrix, ShrinkingMatrix

public interface Matrix
extends Tensor, Iterable<MatrixTuple>

Interface for 2 dimensional Tensors.

Matrices have immutable sizes and immutable indices (so DenseSparseMatrix can't grow).

Method Summary

Modifier and Type	Method and Description
void	add(int i, int j, double value) Adds the argument value to the value at the supplied index.
double	get(int i, int j) Gets an element from this Matrix.
int	getDimension1Size() The size of the first dimension.
int	getDimension2Size() The size of the second dimension.
SGDVector	getRow(int i) Extract a row as an SGDVector.
SGDVector	leftMultiply(SGDVector input) Multiplies this Matrix by a SGDVector returning a vector of the appropriate size.
Matrix	matrixMultiply(Matrix input) Multiplies this Matrix by another Matrix returning a matrix of the appropriate size.
Matrix	matrixMultiply(Matrix input, boolean transposeThis, boolean transposeOther) Multiplies this Matrix by another Matrix returning a matrix of the appropriate size.
int	numActiveElements(int row) The number of non-zero elements in that row.
SGDVector	rightMultiply(SGDVector input) Multiplies this Matrix by a SGDVector returning a vector of the appropriate size.
void	rowScaleInPlace(DenseVector scalingCoefficients) Scales each row by the appropriate value in the DenseVector.
DenseVector	rowSum() Generates a DenseVector representing the sum of each row.
void	set(int i, int j, double value) Sets an element at the supplied location.

Methods inherited from interface org.tribuo.math.la.Tensor

foreachInPlace, getShape, hadamardProductInPlace, hadamardProductInPlace, intersectAndAddInPlace, intersectAndAddInPlace, reshape, scalarAddInPlace, scaleInPlace, shapeCheck, shapeSum, twoNorm

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Method Detail

get

double get(int i,
           int j)

Gets an element from this Matrix.

Parameters:

i - The index for the first dimension.

j - The index for the second dimension.

Returns:

The value at matrix[i][j].

set

void set(int i,
         int j,
         double value)

Sets an element at the supplied location.

Parameters:

i - The index for the first dimension.

j - The index for the second dimension.

value - The value to be stored at matrix[i][j].

add

void add(int i,
         int j,
         double value)

Adds the argument value to the value at the supplied index.

Parameters:

i - The index for the first dimension.

j - The index for the second dimension.

value - The value to add.

getDimension1Size

int getDimension1Size()

The size of the first dimension.

Returns:

The size of the first dimension.

getDimension2Size

int getDimension2Size()

The size of the second dimension.

Returns:

The size of the second dimension.

numActiveElements

int numActiveElements(int row)

The number of non-zero elements in that row.

An element could be active and zero, if it was active on construction.

Parameters:

row - The index of the row.

Returns:

The number of non-zero elements.

leftMultiply

SGDVector leftMultiply(SGDVector input)

Multiplies this Matrix by a SGDVector returning a vector of the appropriate size.

The input must have dimension equal to getDimension2Size().

Parameters:

input - The input vector.

Returns:

A new SGDVector of size getDimension1Size().

rightMultiply

SGDVector rightMultiply(SGDVector input)

Multiplies this Matrix by a SGDVector returning a vector of the appropriate size.

The input must have dimension equal to getDimension1Size().

Parameters:

input - The input vector.

Returns:

A new SGDVector of size getDimension2Size().

matrixMultiply

Matrix matrixMultiply(Matrix input)

Multiplies this Matrix by another Matrix returning a matrix of the appropriate size.

The input must have dimension 1 equal to getDimension2Size().

Parameters:

input - The input matrix.

Returns:

A new Matrix of size getDimension1Size(), input.getDimension2Size().

matrixMultiply

Matrix matrixMultiply(Matrix input,
                      boolean transposeThis,
                      boolean transposeOther)

Multiplies this Matrix by another Matrix returning a matrix of the appropriate size.

Must obey the rules of matrix multiplication after the transposes are applied.

Parameters:

input - The input matrix.

transposeThis - Implicitly transposes this matrix just for the multiplication.

transposeOther - Implicitly transposes other just for the multiplication.

Returns:

A new Matrix.

rowSum

DenseVector rowSum()

Generates a DenseVector representing the sum of each row.

Returns:

A new DenseVector of size getDimension1Size().

rowScaleInPlace

void rowScaleInPlace(DenseVector scalingCoefficients)

Scales each row by the appropriate value in the DenseVector.

Parameters:

scalingCoefficients - A DenseVector with size getDimension1Size().

getRow

SGDVector getRow(int i)

Extract a row as an SGDVector.

This refers to the same values as the matrix, so updating this vector will update the matrix.

Parameters:

i - The index of the row to extract.

Returns:

An SGDVector.