|
|||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | ||||||||||
java.lang.Objectorg.apache.commons.math.linear.RealMatrixImpl
Implementation of RealMatrix using a double[][] array to store entries and LU decompostion to support linear system solution and inverse.
The LU decompostion is performed as needed, to support the following operations:
Usage notes:
getDataRef(), then the stored LU decomposition will not be
discarded. In this case, you need to explicitly invoke
LUDecompose() to recompute the decomposition
before using any of the methods above.RealMatrix interface, matrix element indexing
is 0-based -- e.g., getEntry(0, 0)
returns the element in the first row, first column of the matrix.
| Field Summary | |
protected static double |
TOO_SMALL
Bound to determine effective singularity in LU decomposition |
| Constructor Summary | |
RealMatrixImpl()
Creates a matrix with no data |
|
RealMatrixImpl(double[] v)
Create a new (column) RealMatrix using v as the
data for the unique column of the v.length x 1 matrix
created. |
|
RealMatrixImpl(double[][] d)
Create a new RealMatrix using the input array as the underlying data array. |
|
RealMatrixImpl(int rowDimension,
int columnDimension)
Create a new RealMatrix with the supplied row and column dimensions. |
|
| Method Summary | |
RealMatrix |
add(RealMatrix m)
Compute the sum of this and m. |
RealMatrix |
copy()
Create a new RealMatrix which is a copy of this. |
boolean |
equals(Object object)
Returns true iff object is a
RealMatrixImpl instance with the same dimensions as this
and all corresponding matrix entries are equal. |
double[] |
getColumn(int col)
Returns the entries in column number col as an array. |
int |
getColumnDimension()
Returns the number of columns in the matrix. |
RealMatrix |
getColumnMatrix(int column)
Returns the entries in column number column
as a column matrix. |
double[][] |
getData()
Returns matrix entries as a two-dimensional array. |
double[][] |
getDataRef()
Returns a reference to the underlying data array. |
double |
getDeterminant()
Returns the determinant of this matrix. |
double |
getEntry(int row,
int column)
Returns the entry in the specified row and column. |
protected RealMatrix |
getIdentity(int dimension)
Deprecated. use MatrixUtils.createRealIdentityMatrix(int) |
protected RealMatrix |
getLUMatrix()
Returns the LU decomposition as a RealMatrix. |
double |
getNorm()
Returns the maximum absolute row sum norm of the matrix. |
protected int[] |
getPermutation()
Returns the permutation associated with the lu decomposition. |
double[] |
getRow(int row)
Returns the entries in row number row as an array. |
int |
getRowDimension()
Returns the number of rows in the matrix. |
RealMatrix |
getRowMatrix(int row)
Returns the entries in row number row as a row matrix. |
RealMatrix |
getSubMatrix(int[] selectedRows,
int[] selectedColumns)
Gets a submatrix. |
RealMatrix |
getSubMatrix(int startRow,
int endRow,
int startColumn,
int endColumn)
Gets a submatrix. |
double |
getTrace()
Returns the trace of the matrix (the sum of the elements on the main diagonal). |
int |
hashCode()
Computes a hashcode for the matrix. |
RealMatrix |
inverse()
Returns the inverse matrix if this matrix is invertible. |
boolean |
isSingular()
Is this a singular matrix? |
boolean |
isSquare()
Is this a square matrix? |
void |
luDecompose()
Computes a new LU decompostion for this matrix, storing the result for use by other methods. |
RealMatrix |
multiply(RealMatrix m)
Returns the result of postmultiplying this by m. |
double[] |
operate(double[] v)
Returns the result of multiplying this by the vector v. |
double[] |
preMultiply(double[] v)
Returns the (row) vector result of premultiplying this by the vector v. |
RealMatrix |
preMultiply(RealMatrix m)
Returns the result premultiplying this by m. |
RealMatrix |
scalarAdd(double d)
Returns the result of adding d to each entry of this. |
RealMatrix |
scalarMultiply(double d)
Returns the result multiplying each entry of this by d |
void |
setSubMatrix(double[][] subMatrix,
int row,
int column)
Replace the submatrix starting at row, column using data in
the input subMatrix array. |
double[] |
solve(double[] b)
Returns a matrix of (column) solution vectors for linear systems with coefficient matrix = this and constant vectors = columns of b. |
RealMatrix |
solve(RealMatrix b)
Returns a matrix of (column) solution vectors for linear systems with coefficient matrix = this and constant vectors = columns of b. |
RealMatrix |
subtract(RealMatrix m)
Compute this minus m. |
String |
toString()
|
RealMatrix |
transpose()
Returns the transpose matrix. |
| Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
| Field Detail |
protected static double TOO_SMALL
| Constructor Detail |
public RealMatrixImpl()
public RealMatrixImpl(int rowDimension,
int columnDimension)
rowDimension - the number of rows in the new matrixcolumnDimension - the number of columns in the new matrix
IllegalArgumentException - if row or column dimension is not
positivepublic RealMatrixImpl(double[][] d)
The input array is copied, not referenced.
d - data for new matrix
IllegalArgumentException - if data is not rectangular
(not all rows have the same length) or empty
NullPointerException - if data is nullpublic RealMatrixImpl(double[] v)
v as the
data for the unique column of the v.length x 1 matrix
created.
The input array is copied, not referenced.
v - column vector holding data for new matrix| Method Detail |
public RealMatrix copy()
copy in interface RealMatrix
public RealMatrix add(RealMatrix m)
throws IllegalArgumentException
m.
add in interface RealMatrixm - matrix to be added
IllegalArgumentException - if m is not the same size as this
public RealMatrix subtract(RealMatrix m)
throws IllegalArgumentException
m.
subtract in interface RealMatrixm - matrix to be subtracted
IllegalArgumentException - if m is not the same size as *thispublic RealMatrix scalarAdd(double d)
scalarAdd in interface RealMatrixd - value to be added to each entry
public RealMatrix scalarMultiply(double d)
d
scalarMultiply in interface RealMatrixd - value to multiply all entries by
public RealMatrix multiply(RealMatrix m)
throws IllegalArgumentException
m.
multiply in interface RealMatrixm - matrix to postmultiply by
IllegalArgumentException - if columnDimension(this) != rowDimension(m)
public RealMatrix preMultiply(RealMatrix m)
throws IllegalArgumentException
m.
preMultiply in interface RealMatrixm - matrix to premultiply by
IllegalArgumentException - if rowDimension(this) != columnDimension(m)public double[][] getData()
Makes a fresh copy of the underlying data.
getData in interface RealMatrixpublic double[][] getDataRef()
Does not make a fresh copy of the underlying data.
public double getNorm()
RealMatrix
getNorm in interface RealMatrix
public RealMatrix getSubMatrix(int startRow,
int endRow,
int startColumn,
int endColumn)
throws MatrixIndexException
getSubMatrix in interface RealMatrixstartRow - Initial row indexendRow - Final row indexstartColumn - Initial column indexendColumn - Final column index
MatrixIndexException - if row or column selections are not valid
public RealMatrix getSubMatrix(int[] selectedRows,
int[] selectedColumns)
throws MatrixIndexException
getSubMatrix in interface RealMatrixselectedRows - Array of row indices must be non-emptyselectedColumns - Array of column indices must be non-empty
MatrixIndexException - if supplied row or column index arrays
are not valid
public void setSubMatrix(double[][] subMatrix,
int row,
int column)
throws MatrixIndexException
row, column using data in
the input subMatrix array. Indexes are 0-based.
Example:
Starting with
1 2 3 4 5 6 7 8 9 0 1 2and
subMatrix = {{3, 4} {5,6}}, invoking
setSubMatrix(subMatrix,1,1)) will result in 1 2 3 4 5 3 4 8 9 5 6 2
subMatrix - array containing the submatrix replacement datarow - row coordinate of the top, left element to be replacedcolumn - column coordinate of the top, left element to be replaced
MatrixIndexException - if subMatrix does not fit into this
matrix from element in (row, column)
IllegalArgumentException - if subMatrix is not rectangular
(not all rows have the same length) or empty
NullPointerException - if subMatrix is null
public RealMatrix getRowMatrix(int row)
throws MatrixIndexException
row as a row matrix.
Row indices start at 0.
getRowMatrix in interface RealMatrixrow - the row to be fetched
MatrixIndexException - if the specified row index is invalid
public RealMatrix getColumnMatrix(int column)
throws MatrixIndexException
column
as a column matrix. Column indices start at 0.
getColumnMatrix in interface RealMatrixcolumn - the column to be fetched
MatrixIndexException - if the specified column index is invalid
public double[] getRow(int row)
throws MatrixIndexException
row as an array.
Row indices start at 0. A MatrixIndexException is thrown
unless 0 <= row < rowDimension.
getRow in interface RealMatrixrow - the row to be fetched
MatrixIndexException - if the specified row index is not valid
public double[] getColumn(int col)
throws MatrixIndexException
col as an array.
Column indices start at 0. A MatrixIndexException is thrown
unless 0 <= column < columnDimension.
getColumn in interface RealMatrixcol - the column to be fetched
MatrixIndexException - if the specified column index is not valid
public double getEntry(int row,
int column)
throws MatrixIndexException
Row and column indices start at 0 and must satisfy
0 <= row < rowDimension 0 <= column < columnDimensionMatrixIndexException is thrown.
getEntry in interface RealMatrixrow - row location of entry to be fetchedcolumn - column location of entry to be fetched
MatrixIndexException - if the row or column index is not validpublic RealMatrix transpose()
transpose in interface RealMatrix
public RealMatrix inverse()
throws InvalidMatrixException
inverse in interface RealMatrixInvalidMatrixException - if this is not invertible
public double getDeterminant()
throws InvalidMatrixException
RealMatrix
getDeterminant in interface RealMatrixInvalidMatrixException - if matrix is not squarepublic boolean isSquare()
RealMatrix
isSquare in interface RealMatrixpublic boolean isSingular()
RealMatrix
isSingular in interface RealMatrixpublic int getRowDimension()
RealMatrix
getRowDimension in interface RealMatrixpublic int getColumnDimension()
RealMatrix
getColumnDimension in interface RealMatrix
public double getTrace()
throws IllegalArgumentException
RealMatrix
getTrace in interface RealMatrixIllegalArgumentException - if the matrix is not square
public double[] operate(double[] v)
throws IllegalArgumentException
RealMatrixv.
operate in interface RealMatrixv - vector to operate on
IllegalArgumentException - if columnDimension != v.length
public double[] preMultiply(double[] v)
throws IllegalArgumentException
RealMatrixv.
preMultiply in interface RealMatrixv - vector to premultiply by
IllegalArgumentException - if rowDimension != v.length
public double[] solve(double[] b)
throws IllegalArgumentException,
InvalidMatrixException
b.
solve in interface RealMatrixb - array of constant forming RHS of linear systems to
to solve
IllegalArgumentException - if this.rowDimension != row dimension
InvalidMatrixException - if this matrix is not square or is singular
public RealMatrix solve(RealMatrix b)
throws IllegalArgumentException,
InvalidMatrixException
b.
solve in interface RealMatrixb - matrix of constant vectors forming RHS of linear systems to
to solve
IllegalArgumentException - if this.rowDimension != row dimension
InvalidMatrixException - if this matrix is not square or is singular
public void luDecompose()
throws InvalidMatrixException
Implementation Note:
Uses
Crout's algortithm, with partial pivoting.
Usage Note:
This method should rarely be invoked directly. Its only use is
to force recomputation of the LU decomposition when changes have been
made to the underlying data using direct array references. Changes
made using setXxx methods will trigger recomputation when needed
automatically.
InvalidMatrixException - if the matrix is non-square or singular.public String toString()
Object.toString()public boolean equals(Object object)
object is a
RealMatrixImpl instance with the same dimensions as this
and all corresponding matrix entries are equal. Corresponding entries
are compared using Double.doubleToLongBits(double)
object - the object to test equality against.
public int hashCode()
protected RealMatrix getIdentity(int dimension)
MatrixUtils.createRealIdentityMatrix(int)
dimension x dimension identity matrix.
dimension - dimension of identity matrix to generate
IllegalArgumentException - if dimension is not positive
protected RealMatrix getLUMatrix()
throws InvalidMatrixException
The matrix returned is a compact representation of the LU decomposition. Elements below the main diagonal correspond to entries of the "L" matrix; elements on and above the main diagonal correspond to entries of the "U" matrix.
Example:
Returned matrix L U
2 3 1 1 0 0 2 3 1
5 4 6 5 1 0 0 4 6
1 7 8 1 7 1 0 0 8
The L and U matrices satisfy the matrix equation LU = permuteRows(this),
InvalidMatrixException - if the matrix is non-square or singular.protected int[] getPermutation()
Example: permutation = [1, 2, 0] means current 2nd row is first, current third row is second and current first row is last.
Returns a fresh copy of the array.
|
|||||||||||
| PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||||
| SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD | ||||||||||