Package no.uib.cipr.matrix
Class LowerTriangPackMatrix
- java.lang.Object
-
- no.uib.cipr.matrix.AbstractMatrix
-
- no.uib.cipr.matrix.LowerTriangPackMatrix
-
- All Implemented Interfaces:
java.lang.Iterable<MatrixEntry>
,Matrix
- Direct Known Subclasses:
UnitLowerTriangPackMatrix
public class LowerTriangPackMatrix extends AbstractMatrix
Lower triangular packed matrix. In contrast withLowerTriangDenseMatrix
, this matrix exploits the sparsity by only storing about half the matrix. As such, the triangular matrixa11 a21 a22 a31 a32 a33 a41 a42 a43 a44 is packed as follows:
a11 a21 a31 a41 a22 a32 a42 a33 a43 a44
-
-
Nested Class Summary
-
Nested classes/interfaces inherited from interface no.uib.cipr.matrix.Matrix
Matrix.Norm
-
-
Field Summary
-
Fields inherited from class no.uib.cipr.matrix.AbstractMatrix
numColumns, numRows
-
-
Constructor Summary
Constructors Constructor Description LowerTriangPackMatrix(int n)
Constructor for LowerTriangPackMatrixLowerTriangPackMatrix(Matrix A)
Constructor for LowerTriangPackMatrixLowerTriangPackMatrix(Matrix A, boolean deep)
Constructor for LowerTriangPackMatrix
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
add(int row, int column, double value)
A(row,column) += value
LowerTriangPackMatrix
copy()
Creates a deep copy of the matrixdouble
get(int row, int column)
ReturnsA(row,column)
double[]
getData()
Returns the matrix contents.java.util.Iterator<MatrixEntry>
iterator()
Vector
mult(double alpha, Vector x, Vector y)
y = alpha*A*x
void
set(int row, int column, double value)
A(row,column) = value
Matrix
set(Matrix B)
A=B
.Matrix
solve(Matrix B, Matrix X)
X = A\B
.Vector
solve(Vector b, Vector x)
x = A\b
.Vector
transMult(double alpha, Vector x, Vector y)
y = alpha*AT*x
Matrix
transSolve(Matrix B, Matrix X)
X = AT\B
.Vector
transSolve(Vector b, Vector x)
x = AT\b
.Matrix
zero()
Zeros all the entries in the matrix, while preserving any underlying structure.-
Methods inherited from class no.uib.cipr.matrix.AbstractMatrix
add, add, check, checkMultAdd, checkMultAdd, checkRank1, checkRank1, checkRank2, checkRank2, checkSize, checkSolve, checkSolve, checkTransABmultAdd, checkTransAmultAdd, checkTransBmultAdd, checkTransMultAdd, checkTranspose, checkTranspose, checkTransRank1, checkTransRank2, isSquare, max, max, mult, mult, mult, multAdd, multAdd, multAdd, multAdd, norm, norm1, normF, normInf, numColumns, numRows, rank1, rank1, rank1, rank1, rank1, rank1, rank2, rank2, rank2, rank2, scale, set, toString, transABmult, transABmult, transABmultAdd, transABmultAdd, transAmult, transAmult, transAmultAdd, transAmultAdd, transBmult, transBmult, transBmultAdd, transBmultAdd, transMult, transMultAdd, transMultAdd, transpose, transpose, transRank1, transRank1, transRank2, transRank2
-
-
-
-
Constructor Detail
-
LowerTriangPackMatrix
public LowerTriangPackMatrix(int n)
Constructor for LowerTriangPackMatrix- Parameters:
n
- Size of the matrix. Since the matrix must be square, this equals both the number of rows and columns
-
LowerTriangPackMatrix
public LowerTriangPackMatrix(Matrix A)
Constructor for LowerTriangPackMatrix- Parameters:
A
- Matrix to copy contents from. Only the entries of the relevant part are copied
-
LowerTriangPackMatrix
public LowerTriangPackMatrix(Matrix A, boolean deep)
Constructor for LowerTriangPackMatrix- Parameters:
A
- Matrix to copy contents from. Only the entries of the relevant part are copieddeep
- True if the copy is deep, else false (giving a shallow copy). For shallow copies,A
must be a packed matrix
-
-
Method Detail
-
add
public void add(int row, int column, double value)
Description copied from interface:Matrix
A(row,column) += value
- Specified by:
add
in interfaceMatrix
- Overrides:
add
in classAbstractMatrix
-
set
public void set(int row, int column, double value)
Description copied from interface:Matrix
A(row,column) = value
- Specified by:
set
in interfaceMatrix
- Overrides:
set
in classAbstractMatrix
-
get
public double get(int row, int column)
Description copied from interface:Matrix
ReturnsA(row,column)
- Specified by:
get
in interfaceMatrix
- Overrides:
get
in classAbstractMatrix
-
copy
public LowerTriangPackMatrix copy()
Description copied from interface:Matrix
Creates a deep copy of the matrix- Specified by:
copy
in interfaceMatrix
- Overrides:
copy
in classAbstractMatrix
- Returns:
- A
-
mult
public Vector mult(double alpha, Vector x, Vector y)
Description copied from interface:Matrix
y = alpha*A*x
- Specified by:
mult
in interfaceMatrix
- Overrides:
mult
in classAbstractMatrix
x
- Vector of sizeA.numColumns()
y
- Vector of sizeA.numRows()
- Returns:
- y
-
transMult
public Vector transMult(double alpha, Vector x, Vector y)
Description copied from interface:Matrix
y = alpha*AT*x
- Specified by:
transMult
in interfaceMatrix
- Overrides:
transMult
in classAbstractMatrix
x
- Vector of sizeA.numRows()
y
- Vector of sizeA.numColumns()
- Returns:
- y
-
solve
public Matrix solve(Matrix B, Matrix X)
Description copied from interface:Matrix
X = A\B
. Not all matrices support this operation, those that do not throwUnsupportedOperationException
. Note that it is often more efficient to use a matrix decomposition and its associated solver- Specified by:
solve
in interfaceMatrix
- Overrides:
solve
in classAbstractMatrix
- Parameters:
B
- Matrix with the same number of rows asA
, and the same number of columns asX
X
- Matrix with a number of rows equalA.numColumns()
, and the same number of columns asB
- Returns:
- X
-
solve
public Vector solve(Vector b, Vector x)
Description copied from interface:Matrix
x = A\b
. Not all matrices support this operation, those that do not throwUnsupportedOperationException
. Note that it is often more efficient to use a matrix decomposition and its associated solver- Specified by:
solve
in interfaceMatrix
- Overrides:
solve
in classAbstractMatrix
- Parameters:
b
- Vector of sizeA.numRows()
x
- Vector of sizeA.numColumns()
- Returns:
- x
-
transSolve
public Matrix transSolve(Matrix B, Matrix X)
Description copied from interface:Matrix
X = AT\B
. Not all matrices support this operation, those that do not throwUnsupportedOperationException
. Note that it is often more efficient to use a matrix decomposition and its associated transpose solver- Specified by:
transSolve
in interfaceMatrix
- Overrides:
transSolve
in classAbstractMatrix
- Parameters:
B
- Matrix with a number of rows equalA.numColumns()
, and the same number of columns asX
X
- Matrix with the same number of rows asA
, and the same number of columns asB
- Returns:
- X
-
transSolve
public Vector transSolve(Vector b, Vector x)
Description copied from interface:Matrix
x = AT\b
. Not all matrices support this operation, those that do not throwUnsupportedOperationException
. Note that it is often more efficient to use a matrix decomposition and its associated solver- Specified by:
transSolve
in interfaceMatrix
- Overrides:
transSolve
in classAbstractMatrix
- Parameters:
b
- Vector of sizeA.numColumns()
x
- Vector of sizeA.numRows()
- Returns:
- x
-
iterator
public java.util.Iterator<MatrixEntry> iterator()
- Specified by:
iterator
in interfacejava.lang.Iterable<MatrixEntry>
- Overrides:
iterator
in classAbstractMatrix
-
getData
public double[] getData()
Returns the matrix contents. Ordering depends on the underlying storage assumptions
-
set
public Matrix set(Matrix B)
Description copied from interface:Matrix
A=B
. The matrices must be of the same size- Specified by:
set
in interfaceMatrix
- Overrides:
set
in classAbstractMatrix
- Returns:
- A
-
-