DenseMatrix32F (core 0.29 API)

java.lang.Object
- org.ejml.data.D1Matrix32F
- - org.ejml.data.DenseMatrix32F

All Implemented Interfaces:

java.io.Serializable, Matrix, RealMatrix32F, ReshapeMatrix
```
public class DenseMatrix32F
extends D1Matrix32F
```
DenseMatrix64F is a dense matrix with elements that are 32-bit floats. A matrix is the fundamental data structure in linear algebra. Unlike a sparse matrix, there is no compression in a dense matrix and every element is stored in memory. This allows for fast reads and writes to the matrix.

The matrix is stored internally in a row-major 1D array format:

data[ y*numCols + x ] = data[y][x]

For example:
data =
```
 a[0]  a[1]   a[2]   a[3]
 a[4]  a[5]   a[6]   a[7]
 a[8]  a[9]   a[10]  a[11]
 a[12] a[13]  a[14]  a[15]
 
```
See Also:

Serialized Form

Field Summary
- Fields inherited from class org.ejml.data.D1Matrix32F
  data, numCols, numRows

Constructor Summary

Constructors
Constructor and Description
`DenseMatrix32F()` Default constructor in which nothing is configured.
`DenseMatrix32F(DenseMatrix32F orig)` Creates a new matrix which is equivalent to the provided matrix.
`DenseMatrix32F(float[][] data)` Creates a matrix with the values and shape defined by the 2D array 'data'.
`DenseMatrix32F(int length)` This declares an array that can store a matrix up to the specified length.
`DenseMatrix32F(int numRows, int numCols)` Creates a new Matrix with the specified shape whose elements initially have the value of zero.
`DenseMatrix32F(int numRows, int numCols, boolean rowMajor, float... data)` Creates a new matrix which has the same value as the matrix encoded in the provided array.
`DenseMatrix32F(RealMatrix32F mat)` Creates a new DenseMatrix64F which contains the same information as the provided Matrix64F.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`add(int row, int col, float value)` Adds 'value' to the specified element in the matrix. a_ij = a_ij + value
`DenseMatrix32F`	`copy()` Creates and returns a matrix which is idential to this one.
`float`	`get(int row, int col)` Returns the value of the specified matrix element.
`int`	`getIndex(int row, int col)` Returns the internal array index for the specified row and column.
`int`	`getNumElements()` Returns the number of elements in this matrix, which is equal to the number of rows times the number of columns.
`boolean`	`isInBounds(int row, int col)` Determins if the specified element is inside the bounds of the Matrix.
`void`	`print()` Prints the value of this matrix to the screen.
`void`	`print(java.lang.String format)` Prints the value of this matrix to the screen using the same format as {@link java.io.PrintStream#printf).
`void`	`reshape(int numRows, int numCols, boolean saveValues)` Changes the number of rows and columns in the matrix, allowing its size to grow or shrink.
`void`	`set(int numRows, int numCols, boolean rowMajor, float... data)` Sets this matrix equal to the matrix encoded in the array.
`void`	`set(int row, int col, float value)` Assigns the element in the Matrix to the specified value.
`void`	`set(Matrix original)` Sets this matrix to be identical to the 'original' matrix passed in.
`java.lang.String`	`toString()` Converts the array into a string format for display purposes.
`float`	`unsafe_get(int row, int col)` Same as `RealMatrix32F.get(int, int)` but does not perform bounds check on input parameters.
`void`	`unsafe_set(int row, int col, float value)` Same as `RealMatrix32F.set(int, int, float)` but does not perform bounds check on input parameters.
`static DenseMatrix32F`	`wrap(int numRows, int numCols, float[] data)` Creates a new DenseMatrix64F around the provided data.
`void`	`zero()` Sets all elements equal to zero.

Methods inherited from class org.ejml.data.D1Matrix32F
div, get, getData, getNumCols, getNumRows, iterator, minus, plus, reshape, set, set, setData, setNumCols, setNumRows, times

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

- Constructor Detail
  - DenseMatrix32F
```
public DenseMatrix32F(int numRows,
                      int numCols,
                      boolean rowMajor,
                      float... data)
```
    Creates a new matrix which has the same value as the matrix encoded in the provided array. The input matrix's format can either be row-major or column-major.
    
    Note that 'data' is a variable argument type, so either 1D arrays or a set of numbers can be passed in:
    DenseMatrix a = new DenseMatrix(2,2,true,new float[]{1,2,3,4});
    DenseMatrix b = new DenseMatrix(2,2,true,1,2,3,4);
    
    Both are equivalent.
    
    Parameters:
    
    numRows - The number of rows.
    
    numCols - The number of columns.
    
    rowMajor - If the array is encoded in a row-major or a column-major format.
    
    data - The formatted 1D array. Not modified.
  - DenseMatrix32F
```
public DenseMatrix32F(float[][] data)
```
    Creates a matrix with the values and shape defined by the 2D array 'data'. It is assumed that 'data' has a row-major formatting:
    
    data[ row ][ column ]
    
    Parameters:
    
    data - 2D array representation of the matrix. Not modified.
  - DenseMatrix32F
```
public DenseMatrix32F(int numRows,
                      int numCols)
```
    Creates a new Matrix with the specified shape whose elements initially have the value of zero.
    
    Parameters:
    
    numRows - The number of rows in the matrix.
    
    numCols - The number of columns in the matrix.
  - DenseMatrix32F
```
public DenseMatrix32F(DenseMatrix32F orig)
```
    Creates a new matrix which is equivalent to the provided matrix. Note that the length of the data will be determined by the shape of the matrix.
    
    Parameters:
    
    orig - The matrix which is to be copied. This is not modified or saved.
  - DenseMatrix32F
```
public DenseMatrix32F(int length)
```
    This declares an array that can store a matrix up to the specified length. This is use full when a matrix's size will be growing and it is desirable to avoid reallocating memory.
    
    Parameters:
    
    length - The size of the matrice's data array.
  - DenseMatrix32F
```
public DenseMatrix32F()
```
    Default constructor in which nothing is configured. THIS IS ONLY PUBLICLY ACCESSIBLE SO THAT THIS CLASS CAN BE A JAVA BEAN. DON'T USE IT UNLESS YOU REALLY KNOW WHAT YOU'RE DOING!
  - DenseMatrix32F
```
public DenseMatrix32F(RealMatrix32F mat)
```
    Creates a new DenseMatrix64F which contains the same information as the provided Matrix64F.
    
    Parameters:
    
    mat - Matrix whose values will be copied. Not modified.
- Method Detail
  - wrap
```
public static DenseMatrix32F wrap(int numRows,
                                  int numCols,
                                  float[] data)
```
    Creates a new DenseMatrix64F around the provided data. The data must encode a row-major matrix. Any modification to the returned matrix will modify the provided data.
    
    Parameters:
    
    numRows - Number of rows in the matrix.
    
    numCols - Number of columns in the matrix.
    
    data - Data that is being wrapped. Referenced Saved.
    
    Returns:
    
    A matrix which references the provided data internally.
  - reshape
```
public void reshape(int numRows,
                    int numCols,
                    boolean saveValues)
```
    Description copied from class: D1Matrix32F
    
    Changes the number of rows and columns in the matrix, allowing its size to grow or shrink. If the saveValues flag is set to true, then the previous values will be maintained, but reassigned to new elements in a row-major ordering. If saveValues is false values will only be maintained when the requested size is less than or equal to the internal array size. The primary use for this function is to encourage data reuse and avoid unnecessarily declaring and initialization of new memory.
    
    Examples:
    [ 1 2 ; 3 4 ] -> reshape( 2 , 3 , true ) = [ 1 2 3 ; 4 0 0 ]
    [ 1 2 ; 3 4 ] -> reshape( 1 , 2 , true ) = [ 1 2 ]
    [ 1 2 ; 3 4 ] -> reshape( 1 , 2 , false ) = [ 1 2 ]
    [ 1 2 ; 3 4 ] -> reshape( 2 , 3 , false ) = [ 0 0 0 ; 0 0 0 ]
    
    Specified by:
    
    reshape in class D1Matrix32F
    
    Parameters:
    
    numRows - The new number of rows in the matrix.
    
    numCols - The new number of columns in the matrix.
    
    saveValues - If true then the value of each element will be save using a row-major reordering. Typically this should be false.
  - set
```
public void set(int row,
                int col,
                float value)
```
    Assigns the element in the Matrix to the specified value. Performs a bounds check to make sure the requested element is part of the matrix.
    
    a_ij = value
    
    Parameters:
    
    row - The row of the element.
    
    col - The column of the element.
    
    value - The element's new value.
  - unsafe_set
```
public void unsafe_set(int row,
                       int col,
                       float value)
```
    Description copied from interface: RealMatrix32F
    
    Same as RealMatrix32F.set(int, int, float) but does not perform bounds check on input parameters. This results in about a 25% speed increase but potentially sacrifices stability and makes it more difficult to track down simple errors. It is not recommended that this function be used, except in highly optimized code where the bounds are implicitly being checked.
    
    Parameters:
    
    row - Matrix element's row index..
    
    col - Matrix element's column index.
    
    value - The element's new value.
  - add
```
public void add(int row,
                int col,
                float value)
```
    Adds 'value' to the specified element in the matrix.
    
    a_ij = a_ij + value
    
    Parameters:
    
    row - The row of the element.
    
    col - The column of the element.
    
    value - The value that is added to the element
  - get
```
public float get(int row,
                 int col)
```
    Returns the value of the specified matrix element. Performs a bounds check to make sure the requested element is part of the matrix.
    
    Parameters:
    
    row - The row of the element.
    
    col - The column of the element.
    
    Returns:
    
    The value of the element.
  - unsafe_get
```
public float unsafe_get(int row,
                        int col)
```
    Description copied from interface: RealMatrix32F
    
    Same as RealMatrix32F.get(int, int) but does not perform bounds check on input parameters. This results in about a 25% speed increase but potentially sacrifices stability and makes it more difficult to track down simple errors. It is not recommended that this function be used, except in highly optimized code where the bounds are implicitly being checked.
    
    Parameters:
    
    row - Matrix element's row index..
    
    col - Matrix element's column index.
    
    Returns:
    
    The specified element's value.
  - getIndex
```
public int getIndex(int row,
                    int col)
```
    Description copied from class: D1Matrix32F
    
    Returns the internal array index for the specified row and column.
    
    Specified by:
    
    getIndex in class D1Matrix32F
    
    Parameters:
    
    row - Row index.
    
    col - Column index.
    
    Returns:
    
    Internal array index.
  - isInBounds
```
public boolean isInBounds(int row,
                          int col)
```
    Determins if the specified element is inside the bounds of the Matrix.
    
    Parameters:
    
    row - The element's row.
    
    col - The elements' column.
    
    Returns:
    
    True if it is inside the matrices bound, false otherwise.
  - getNumElements
```
public int getNumElements()
```
    Returns the number of elements in this matrix, which is equal to the number of rows times the number of columns.
    
    Returns:
    
    The number of elements in the matrix.
  - set
```
public void set(int numRows,
                int numCols,
                boolean rowMajor,
                float... data)
```
    Sets this matrix equal to the matrix encoded in the array.
    
    Parameters:
    
    numRows - The number of rows.
    
    numCols - The number of columns.
    
    rowMajor - If the array is encoded in a row-major or a column-major format.
    
    data - The formatted 1D array. Not modified.
  - zero
```
public void zero()
```
    Sets all elements equal to zero.
  - copy
```
public DenseMatrix32F copy()
```
    Creates and returns a matrix which is idential to this one.
    
    Returns:
    
    A new identical matrix.
  - set
```
public void set(Matrix original)
```
    Description copied from interface: Matrix
    
    Sets this matrix to be identical to the 'original' matrix passed in.
  - print
```
public void print()
```
    Prints the value of this matrix to the screen. For more options see UtilEjml
  - print
```
public void print(java.lang.String format)
```
    Prints the value of this matrix to the screen using the same format as {@link java.io.PrintStream#printf).
    
    Parameters:
    
    format - The format which each element is printed uses.
  - toString
```
public java.lang.String toString()
```
    Converts the array into a string format for display purposes. The conversion is done using MatrixIO.print(java.io.PrintStream, org.ejml.data.RealMatrix64F).
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    String representation of the matrix.

Class DenseMatrix32F

Field Summary

Fields inherited from class org.ejml.data.D1Matrix32F

Constructor Summary

Method Summary

Methods inherited from class org.ejml.data.D1Matrix32F

Methods inherited from class java.lang.Object

Constructor Detail

DenseMatrix32F

DenseMatrix32F

DenseMatrix32F

DenseMatrix32F

DenseMatrix32F

DenseMatrix32F

DenseMatrix32F

Method Detail

wrap

reshape

set

unsafe_set

add

get

unsafe_get

getIndex

isInBounds

getNumElements

set

zero

copy

set

print

print

toString