java.lang.Object
- no.uib.cipr.matrix.AbstractMatrix
- - no.uib.cipr.matrix.TridiagMatrix

All Implemented Interfaces:

java.lang.Iterable<MatrixEntry>, Matrix
```
public class TridiagMatrix
extends AbstractMatrix
```
Tridiagonal matrix. Stored in three arrays, one of length n for the diagonal, two of length n-1 for the superdiagonal and subdiagonal entries.

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
`TridiagMatrix(int n)`	Constructor for TridiagMatrix
`TridiagMatrix(Matrix A)`	Constructor for TridiagMatrix
`TridiagMatrix(Matrix A, boolean deep)`	Constructor for TridiagMatrix

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`
`TridiagMatrix`	`copy()`	Creates a deep copy of the matrix
`double`	`get(int row, int column)`	Returns `A(row,column)`
`double[]`	`getDiagonal()`	Returns the diagonal entries.
`double[]`	`getSubDiagonal()`	Returns the sub diagonal entries.
`double[]`	`getSuperDiagonal()`	Returns the super diagonal entries.
`java.util.Iterator<MatrixEntry>`	`iterator()`
`void`	`set(int row, int column, double value)`	`A(row,column) = value`
`Matrix`	`solve(Matrix B, Matrix X)`	`X = A\B`.
`Vector`	`solve(Vector b, Vector x)`	`x = A\b`.
`Matrix`	`transpose()`	Transposes the matrix in-place.
`TridiagMatrix`	`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, mult, multAdd, multAdd, multAdd, multAdd, norm, norm1, normF, normInf, numColumns, numRows, rank1, rank1, rank1, rank1, rank1, rank1, rank2, rank2, rank2, rank2, scale, set, set, toString, transABmult, transABmult, transABmultAdd, transABmultAdd, transAmult, transAmult, transAmultAdd, transAmultAdd, transBmult, transBmult, transBmultAdd, transBmultAdd, transMult, transMult, transMultAdd, transMultAdd, transpose, transRank1, transRank1, transRank2, transRank2, transSolve, transSolve

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Constructor Detail
  - TridiagMatrix
```
public TridiagMatrix(int n)
```
    Constructor for TridiagMatrix
    
    Parameters:
    
    n - Size of the matrix. Since the matrix must be square, this equals both the number of rows and columns
  - TridiagMatrix
```
public TridiagMatrix(Matrix A)
```
    Constructor for TridiagMatrix
    
    Parameters:
    
    A - Matrix to copy from. Only the tridiagonal part is copied
  - TridiagMatrix
```
public TridiagMatrix(Matrix A,
                     boolean deep)
```
    Constructor for TridiagMatrix
    
    Parameters:
    
    A - Matrix to copy from. Only the tridiagonal part is copied
    
    deep - True for a deep copy, else it's shallow. For shallow copies, A must be a TridiagMatrix
- Method Detail
  - getDiagonal
```
public double[] getDiagonal()
```
    Returns the diagonal entries. Length equal n
  - getSubDiagonal
```
public double[] getSubDiagonal()
```
    Returns the sub diagonal entries. Length equal n-1
  - getSuperDiagonal
```
public double[] getSuperDiagonal()
```
    Returns the super diagonal entries. Length equal n-1
  - add
```
public void add(int row,
                int column,
                double value)
```
    Description copied from interface: Matrix
    
    A(row,column) += value
    
    Specified by:
    
    add in interface Matrix
    
    Overrides:
    
    add in class AbstractMatrix
  - get
```
public double get(int row,
                  int column)
```
    Description copied from interface: Matrix
    
    Returns A(row,column)
    
    Specified by:
    
    get in interface Matrix
    
    Overrides:
    
    get in class AbstractMatrix
  - set
```
public void set(int row,
                int column,
                double value)
```
    Description copied from interface: Matrix
    
    A(row,column) = value
    
    Specified by:
    
    set in interface Matrix
    
    Overrides:
    
    set in class AbstractMatrix
  - copy
```
public TridiagMatrix copy()
```
    Description copied from interface: Matrix
    
    Creates a deep copy of the matrix
    
    Specified by:
    
    copy in interface Matrix
    
    Overrides:
    
    copy in class AbstractMatrix
    
    Returns:
    
    A
  - zero
```
public TridiagMatrix zero()
```
    Description copied from interface: Matrix
    
    Zeros all the entries in the matrix, while preserving any underlying structure. Useful for general, unstructured matrices.
    
    Specified by:
    
    zero in interface Matrix
    
    Overrides:
    
    zero in class AbstractMatrix
    
    Returns:
    
    A
  - 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 throw UnsupportedOperationException. Note that it is often more efficient to use a matrix decomposition and its associated solver
    
    Specified by:
    
    solve in interface Matrix
    
    Overrides:
    
    solve in class AbstractMatrix
    
    Parameters:
    
    B - Matrix with the same number of rows as A, and the same number of columns as X
    
    X - Matrix with a number of rows equal A.numColumns(), and the same number of columns as B
    
    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 throw UnsupportedOperationException. Note that it is often more efficient to use a matrix decomposition and its associated solver
    
    Specified by:
    
    solve in interface Matrix
    
    Overrides:
    
    solve in class AbstractMatrix
    
    Parameters:
    
    b - Vector of size A.numRows()
    
    x - Vector of size A.numColumns()
    
    Returns:
    
    x
  - transpose
```
public Matrix transpose()
```
    Description copied from interface: Matrix
    
    Transposes the matrix in-place. In most cases, the matrix must be square for this to work.
    
    Specified by:
    
    transpose in interface Matrix
    
    Overrides:
    
    transpose in class AbstractMatrix
    
    Returns:
    
    This matrix
  - iterator
```
public java.util.Iterator<MatrixEntry> iterator()
```
    Specified by:
    
    iterator in interface java.lang.Iterable<MatrixEntry>
    
    Overrides:
    
    iterator in class AbstractMatrix

Class TridiagMatrix

Nested Class Summary

Nested classes/interfaces inherited from interface no.uib.cipr.matrix.Matrix

Field Summary

Fields inherited from class no.uib.cipr.matrix.AbstractMatrix

Constructor Summary

Method Summary

Methods inherited from class no.uib.cipr.matrix.AbstractMatrix

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.Iterable

Constructor Detail

TridiagMatrix

TridiagMatrix

TridiagMatrix

Method Detail

getDiagonal

getSubDiagonal

getSuperDiagonal

add

get

set

copy

zero

solve

solve

transpose

iterator