org.apache.spark.mllib.linalg

Class Matrices

Object

org.apache.spark.mllib.linalg.Matrices

public class Matrices
extends Object

Factory methods for Matrix.

Constructor Summary

Constructors

Constructor and Description
Matrices()

Method Summary

Methods

Modifier and Type	Method and Description
static Matrix	dense(int numRows, int numCols, double[] values) Creates a column-major dense matrix.
static Matrix	diag(Vector vector) Generate a diagonal matrix in Matrix format from the supplied values.
static Matrix	eye(int n) Generate a dense Identity Matrix in Matrix format.
static Matrix	fromBreeze(breeze.linalg.Matrix<Object> breeze) Creates a Matrix instance from a breeze matrix.
static Matrix	horzcat(Matrix[] matrices) Horizontally concatenate a sequence of matrices.
static Matrix	ones(int numRows, int numCols) Generate a DenseMatrix consisting of ones.
static Matrix	rand(int numRows, int numCols, java.util.Random rng) Generate a DenseMatrix consisting of i.i.d. uniform random numbers.
static Matrix	randn(int numRows, int numCols, java.util.Random rng) Generate a DenseMatrix consisting of i.i.d. gaussian random numbers.
static Matrix	sparse(int numRows, int numCols, int[] colPtrs, int[] rowIndices, double[] values) Creates a column-major sparse matrix in Compressed Sparse Column (CSC) format.
static Matrix	speye(int n) Generate a sparse Identity Matrix in Matrix format.
static Matrix	sprand(int numRows, int numCols, double density, java.util.Random rng) Generate a SparseMatrix consisting of i.i.d. gaussian random numbers.
static Matrix	sprandn(int numRows, int numCols, double density, java.util.Random rng) Generate a SparseMatrix consisting of i.i.d. gaussian random numbers.
static Matrix	vertcat(Matrix[] matrices) Vertically concatenate a sequence of matrices.
static Matrix	zeros(int numRows, int numCols) Generate a Matrix consisting of zeros.

Methods inherited from class Object

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

Constructor Detail

Matrices

public Matrices()

Method Detail

dense

public static Matrix dense(int numRows,
           int numCols,
           double[] values)

Creates a column-major dense matrix.

Parameters:

numRows - number of rows

numCols - number of columns

values - matrix entries in column major

sparse

public static Matrix sparse(int numRows,
            int numCols,
            int[] colPtrs,
            int[] rowIndices,
            double[] values)

Creates a column-major sparse matrix in Compressed Sparse Column (CSC) format.

Parameters:

numRows - number of rows

numCols - number of columns

colPtrs - the index corresponding to the start of a new column

rowIndices - the row index of the entry

values - non-zero matrix entries in column major

fromBreeze

public static Matrix fromBreeze(breeze.linalg.Matrix<Object> breeze)

Creates a Matrix instance from a breeze matrix.

Parameters:

breeze - a breeze matrix

Returns:

a Matrix instance

zeros

public static Matrix zeros(int numRows,
           int numCols)

Generate a Matrix consisting of zeros.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

Returns:

Matrix with size numRows x numCols and values of zeros

ones

public static Matrix ones(int numRows,
          int numCols)

Generate a DenseMatrix consisting of ones.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

Returns:

Matrix with size numRows x numCols and values of ones

eye

public static Matrix eye(int n)

Generate a dense Identity Matrix in Matrix format.

Parameters:

n - number of rows and columns of the matrix

Returns:

Matrix with size n x n and values of ones on the diagonal

speye

public static Matrix speye(int n)

Generate a sparse Identity Matrix in Matrix format.

Parameters:

n - number of rows and columns of the matrix

Returns:

Matrix with size n x n and values of ones on the diagonal

rand

public static Matrix rand(int numRows,
          int numCols,
          java.util.Random rng)

Generate a DenseMatrix consisting of i.i.d. uniform random numbers.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

rng - a random number generator

Returns:

Matrix with size numRows x numCols and values in U(0, 1)

sprand

public static Matrix sprand(int numRows,
            int numCols,
            double density,
            java.util.Random rng)

Generate a SparseMatrix consisting of i.i.d. gaussian random numbers.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

density - the desired density for the matrix

rng - a random number generator

Returns:

Matrix with size numRows x numCols and values in U(0, 1)

randn

public static Matrix randn(int numRows,
           int numCols,
           java.util.Random rng)

Generate a DenseMatrix consisting of i.i.d. gaussian random numbers.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

rng - a random number generator

Returns:

Matrix with size numRows x numCols and values in N(0, 1)

sprandn

public static Matrix sprandn(int numRows,
             int numCols,
             double density,
             java.util.Random rng)

Generate a SparseMatrix consisting of i.i.d. gaussian random numbers.

Parameters:

numRows - number of rows of the matrix

numCols - number of columns of the matrix

density - the desired density for the matrix

rng - a random number generator

Returns:

Matrix with size numRows x numCols and values in N(0, 1)

diag

public static Matrix diag(Vector vector)

Generate a diagonal matrix in Matrix format from the supplied values.

Parameters:

vector - a Vector that will form the values on the diagonal of the matrix

Returns:

Square Matrix with size values.length x values.length and values on the diagonal

horzcat

public static Matrix horzcat(Matrix[] matrices)

Horizontally concatenate a sequence of matrices. The returned matrix will be in the format the matrices are supplied in. Supplying a mix of dense and sparse matrices will result in a sparse matrix. If the Array is empty, an empty DenseMatrix will be returned.

Parameters:

matrices - array of matrices

Returns:

a single Matrix composed of the matrices that were horizontally concatenated

vertcat

public static Matrix vertcat(Matrix[] matrices)

Vertically concatenate a sequence of matrices. The returned matrix will be in the format the matrices are supplied in. Supplying a mix of dense and sparse matrices will result in a sparse matrix. If the Array is empty, an empty DenseMatrix will be returned.

Parameters:

matrices - array of matrices

Returns:

a single Matrix composed of the matrices that were vertically concatenated