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java.lang.Objectcern.colt.PersistentObject
cern.colt.matrix.AbstractMatrix
cern.colt.matrix.AbstractMatrix2D
cern.colt.matrix.tdouble.DoubleMatrix2D
public abstract class DoubleMatrix2D
Abstract base class for 2-d matrices holding double elements. First see the package summary and javadoc tree view to get the broad picture.
A matrix has a number of rows and columns, which are assigned upon instance construction - The matrix's size is then rows()*columns(). Elements are accessed via [row,column] coordinates. Legal coordinates range from [0,0] to [rows()-1,columns()-1]. Any attempt to access an element at a coordinate column<0 || column>=columns() || row<0 || row>=rows() will throw an IndexOutOfBoundsException.
Note that this implementation is not synchronized.
| Field Summary |
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| Fields inherited from class cern.colt.PersistentObject |
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serialVersionUID |
| Method Summary | |
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double |
aggregate(DoubleDoubleFunction aggr,
DoubleFunction f)
Applies a function to each cell and aggregates the results. |
double |
aggregate(DoubleDoubleFunction aggr,
DoubleFunction f,
DoubleProcedure cond)
Applies a function to each cell that satisfies a condition and aggregates the results. |
double |
aggregate(DoubleDoubleFunction aggr,
DoubleFunction f,
IntArrayList rowList,
IntArrayList columnList)
Applies a function to all cells with a given indices and aggregates the results. |
double |
aggregate(DoubleMatrix2D other,
DoubleDoubleFunction aggr,
DoubleDoubleFunction f)
Applies a function to each corresponding cell of two matrices and aggregates the results. |
DoubleMatrix2D |
assign(double value)
Sets all cells to the state specified by value. |
DoubleMatrix2D |
assign(double[] values)
Sets all cells to the state specified by values. |
DoubleMatrix2D |
assign(double[][] values)
Sets all cells to the state specified by values. |
DoubleMatrix2D |
assign(DoubleFunction f)
Assigns the result of a function to each cell; x[row,col] = function(x[row,col]). |
DoubleMatrix2D |
assign(DoubleMatrix2D other)
Replaces all cell values of the receiver with the values of another matrix. |
DoubleMatrix2D |
assign(DoubleMatrix2D y,
DoubleDoubleFunction function)
Assigns the result of a function to each cell; x[row,col] = function(x[row,col],y[row,col]). |
DoubleMatrix2D |
assign(DoubleMatrix2D y,
DoubleDoubleFunction function,
IntArrayList rowList,
IntArrayList columnList)
Assigns the result of a function to all cells with a given indices |
DoubleMatrix2D |
assign(DoubleProcedure cond,
double value)
Assigns a value to all cells that satisfy a condition. |
DoubleMatrix2D |
assign(DoubleProcedure cond,
DoubleFunction f)
Assigns the result of a function to all cells that satisfy a condition. |
DoubleMatrix2D |
assign(float[] values)
Sets all cells to the state specified by values. |
int |
cardinality()
Returns the number of cells having non-zero values; ignores tolerance. |
DoubleMatrix2D |
copy()
Constructs and returns a deep copy of the receiver. |
abstract void |
dct2(boolean scale)
Computes the 2D discrete cosine transform (DCT-II) of this matrix. |
abstract void |
dctColumns(boolean scale)
Computes the discrete cosine transform (DCT-II) of each column of this matrix. |
abstract void |
dctRows(boolean scale)
Computes the discrete cosine transform (DCT-II) of each row of this matrix. |
abstract void |
dht2()
Computes the 2D discrete Hartley transform (DHT) of this matrix. |
abstract void |
dhtColumns()
Computes the discrete Hartley transform (DHT) of each column of this matrix. |
abstract void |
dhtRows()
Computes the discrete Hartley transform (DHT) of each row of this matrix. |
abstract void |
dst2(boolean scale)
Computes the 2D discrete sine transform (DST-II) of this matrix. |
abstract void |
dstColumns(boolean scale)
Computes the discrete sine transform (DST-II) of each column of this matrix. |
abstract void |
dstRows(boolean scale)
Computes the discrete sine transform (DST-II) of each row of this matrix. |
abstract Object |
elements()
Returns the elements of this matrix. |
boolean |
equals(double value)
Returns whether all cells are equal to the given value. |
boolean |
equals(Object obj)
Compares this object against the specified object. |
abstract void |
fft2()
Computes the 2D discrete Fourier transform (DFT) of this matrix. |
DoubleMatrix2D |
forEachNonZero(IntIntDoubleFunction function)
Assigns the result of a function to each non-zero cell; x[row,col] = function(x[row,col]). |
double |
get(int row,
int column)
Returns the matrix cell value at coordinate [row,column]. |
abstract DComplexMatrix2D |
getFft2()
Returns new complex matrix which is the 2D discrete Fourier transform (DFT) of this matrix. |
abstract DComplexMatrix2D |
getFftColumns()
Returns new complex matrix which is the discrete Fourier transform (DFT) of each column of this matrix. |
abstract DComplexMatrix2D |
getFftRows()
Returns new complex matrix which is the discrete Fourier transform (DFT) of each row of this matrix. |
abstract DComplexMatrix2D |
getIfft2(boolean scale)
Returns new complex matrix which is the 2D inverse of the discrete Fourier transform (IDFT) of this matrix. |
abstract DComplexMatrix2D |
getIfftColumns(boolean scale)
Returns new complex matrix which is the inverse of the discrete Fourier transform (IDFT) of each column of this matrix. |
abstract DComplexMatrix2D |
getIfftRows(boolean scale)
Returns new complex matrix which is the inverse of the discrete Fourier transform (IDFT) of each row of this matrix. |
double[] |
getMaxLocation()
Return the maximum value of this matrix together with its location |
double[] |
getMinLocation()
Return the minimum value of this matrix together with its location |
void |
getNegativeValues(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
Fills the coordinates and values of cells having negative values into the specified lists. |
void |
getNonZeros(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
Fills the coordinates and values of cells having non-zero values into the specified lists. |
void |
getPositiveValues(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
Fills the coordinates and values of cells having positive values into the specified lists. |
abstract double |
getQuick(int row,
int column)
Returns the matrix cell value at coordinate [row,column]. |
abstract void |
idct2(boolean scale)
Computes the 2D inverse of the discrete cosine transform (DCT-III) of this matrix. |
abstract void |
idctColumns(boolean scale)
Computes the inverse of the discrete cosine transform (DCT-III) of each column of this matrix. |
abstract void |
idctRows(boolean scale)
Computes the inverse of the discrete cosine transform (DCT-III) of each row of this matrix. |
abstract void |
idht2(boolean scale)
Computes the 2D inverse of the discrete Hartley transform (IDHT) of this matrix. |
abstract void |
idhtColumns(boolean scale)
Computes the inverse of the discrete Hartley transform (IDHT) of each column of this matrix. |
abstract void |
idhtRows(boolean scale)
Computes the inverse of the discrete Hartley transform (IDHT) of each row of this matrix. |
abstract void |
idst2(boolean scale)
Computes the 2D inverse of the discrete sine transform (DST-III) of this matrix. |
abstract void |
idstColumns(boolean scale)
Computes the inverse of the discrete sine transform (DST-III) of each column of this matrix. |
abstract void |
idstRows(boolean scale)
Computes the inverse of the discrete sine transform (DST-III) of each row of this matrix. |
abstract void |
ifft2(boolean scale)
Computes the 2D inverse of the discrete Fourier transform (IDFT) of this matrix. |
DoubleMatrix2D |
like()
Construct and returns a new empty matrix of the same dynamic type as the receiver, having the same number of rows and columns. |
abstract DoubleMatrix2D |
like(int rows,
int columns)
Construct and returns a new empty matrix of the same dynamic type as the receiver, having the specified number of rows and columns. |
abstract DoubleMatrix1D |
like1D(int size)
Construct and returns a new 1-d matrix of the corresponding dynamic type, entirelly independent of the receiver. |
void |
normalize()
Normalizes this matrix, i.e. |
void |
set(int row,
int column,
double value)
Sets the matrix cell at coordinate [row,column] to the specified value. |
void |
setNcolumns(int columns)
Sets the number of rows of this matrix |
void |
setNrows(int rows)
Sets the number of rows of this matrix |
abstract void |
setQuick(int row,
int column,
double value)
Sets the matrix cell at coordinate [row,column] to the specified value. |
double[][] |
toArray()
Constructs and returns a 2-dimensional array containing the cell values. |
String |
toString()
Returns a string representation using default formatting. |
abstract DoubleMatrix1D |
vectorize()
Returns a vector obtained by stacking the columns of the matrix on top of one another. |
DoubleMatrix1D |
viewColumn(int column)
Constructs and returns a new slice view representing the rows of the given column. |
DoubleMatrix2D |
viewColumnFlip()
Constructs and returns a new flip view along the column axis. |
DoubleMatrix2D |
viewDice()
Constructs and returns a new dice (transposition) view; Swaps axes; example: 3 x 4 matrix --> 4 x 3 matrix. |
DoubleMatrix2D |
viewPart(int row,
int column,
int height,
int width)
Constructs and returns a new sub-range view that is a height x width sub matrix starting at [row,column]. |
DoubleMatrix1D |
viewRow(int row)
Constructs and returns a new slice view representing the columns of the given row. |
DoubleMatrix2D |
viewRowFlip()
Constructs and returns a new flip view along the row axis. |
DoubleMatrix2D |
viewSelection(DoubleMatrix1DProcedure condition)
Constructs and returns a new selection view that is a matrix holding all rows matching the given condition. |
DoubleMatrix2D |
viewSelection(int[] rowIndexes,
int[] columnIndexes)
Constructs and returns a new selection view that is a matrix holding the indicated cells. |
DoubleMatrix2D |
viewSelection(Set<int[]> indexes)
|
DoubleMatrix2D |
viewSorted(int column)
Sorts the matrix rows into ascending order, according to the natural ordering of the matrix values in the given column. |
DoubleMatrix2D |
viewStrides(int rowStride,
int columnStride)
Constructs and returns a new stride view which is a sub matrix consisting of every i-th cell. |
void |
zAssign8Neighbors(DoubleMatrix2D B,
Double9Function function)
8 neighbor stencil transformation. |
DoubleMatrix1D |
zMult(DoubleMatrix1D y,
DoubleMatrix1D z)
Linear algebraic matrix-vector multiplication; z = A * y; Equivalent to return A.zMult(y,z,1,0); |
DoubleMatrix1D |
zMult(DoubleMatrix1D y,
DoubleMatrix1D z,
double alpha,
double beta,
boolean transposeA)
Linear algebraic matrix-vector multiplication; z = alpha * A * y + beta*z. |
DoubleMatrix2D |
zMult(DoubleMatrix2D B,
DoubleMatrix2D C)
Linear algebraic matrix-matrix multiplication; C = A x B; Equivalent to A.zMult(B,C,1,0,false,false). |
DoubleMatrix2D |
zMult(DoubleMatrix2D B,
DoubleMatrix2D C,
double alpha,
double beta,
boolean transposeA,
boolean transposeB)
Linear algebraic matrix-matrix multiplication; C = alpha * A x B + beta*C. |
double |
zSum()
Returns the sum of all cells; Sum( x[i,j] ). |
| Methods inherited from class cern.colt.matrix.AbstractMatrix2D |
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checkShape, checkShape, columns, columnStride, index, rows, rowStride, size, toStringShort |
| Methods inherited from class cern.colt.matrix.AbstractMatrix |
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ensureCapacity, isView, trimToSize |
| Methods inherited from class cern.colt.PersistentObject |
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clone |
| Methods inherited from class java.lang.Object |
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getClass, hashCode, notify, notifyAll, wait, wait, wait |
| Method Detail |
|---|
public double aggregate(DoubleDoubleFunction aggr,
DoubleFunction f)
Example:
cern.jet.math.Functions F = cern.jet.math.Functions.functions;
2 x 2 matrix
0 1
2 3
// Sum( x[row,col]*x[row,col] )
matrix.aggregate(F.plus,F.square);
--> 14
For further examples, see the package doc.
aggr - an aggregation function taking as first argument the current
aggregation and as second argument the transformed current
cell value.f - a function transforming the current cell value.
DoubleFunctions
public double aggregate(DoubleDoubleFunction aggr,
DoubleFunction f,
DoubleProcedure cond)
aggr - an aggregation function taking as first argument the current
aggregation and as second argument the transformed current
cell value.f - a function transforming the current cell value.cond - a condition.
DoubleFunctions
public double aggregate(DoubleDoubleFunction aggr,
DoubleFunction f,
IntArrayList rowList,
IntArrayList columnList)
aggr - an aggregation function taking as first argument the current
aggregation and as second argument the transformed current
cell value.f - a function transforming the current cell value.rowList - row indices.columnList - column indices.
DoubleFunctions
public double aggregate(DoubleMatrix2D other,
DoubleDoubleFunction aggr,
DoubleDoubleFunction f)
Example:
cern.jet.math.Functions F = cern.jet.math.Functions.functions;
x == 2 x 2 matrix
0 1
2 3
y == 2 x 2 matrix
0 1
2 3
// Sum( x[row,col] * y[row,col] )
x.aggregate(y, F.plus, F.mult);
--> 14
// Sum( (x[row,col] + y[row,col])ˆ2 )
x.aggregate(y, F.plus, F.chain(F.square,F.plus));
--> 56
For further examples, see the package doc.
aggr - an aggregation function taking as first argument the current
aggregation and as second argument the transformed current
cell values.f - a function transforming the current cell values.
IllegalArgumentException - if
columns() != other.columns() || rows() != other.rows()DoubleFunctionspublic DoubleMatrix2D assign(DoubleFunction f)
Example:
matrix = 2 x 2 matrix
0.5 1.5
2.5 3.5
// change each cell to its sine
matrix.assign(cern.jet.math.Functions.sin);
-->
2 x 2 matrix
0.479426 0.997495
0.598472 -0.350783
For further examples, see the package doc.
f - a function object taking as argument the current cell's value.
DoubleFunctions
public DoubleMatrix2D assign(DoubleProcedure cond,
DoubleFunction f)
cond - a condition.f - a function object.
DoubleFunctions
public DoubleMatrix2D assign(DoubleProcedure cond,
double value)
cond - a condition.value - a value.
public DoubleMatrix2D assign(double value)
value - the value to be filled into the cells.
public DoubleMatrix2D assign(double[] values)
The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.
values - the values to be filled into the cells.
IllegalArgumentException - if values.length != rows()*columns().public DoubleMatrix2D assign(double[][] values)
The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.
values - the values to be filled into the cells.
IllegalArgumentException - if
values.length != rows() || for any 0 <= row < rows(): values[row].length != columns()
.public DoubleMatrix2D assign(DoubleMatrix2D other)
other - the source matrix to copy from (may be identical to the
receiver).
IllegalArgumentException - if
columns() != other.columns() || rows() != other.rows()
public DoubleMatrix2D assign(DoubleMatrix2D y,
DoubleDoubleFunction function)
Example:
// assign x[row,col] = x[row,col]<sup>y[row,col]</sup>
m1 = 2 x 2 matrix
0 1
2 3
m2 = 2 x 2 matrix
0 2
4 6
m1.assign(m2, cern.jet.math.Functions.pow);
-->
m1 == 2 x 2 matrix
1 1
16 729
For further examples, see the package doc.
y - the secondary matrix to operate on.function - a function object taking as first argument the current cell's
value of this, and as second argument the current
cell's value of y,
IllegalArgumentException - if
columns() != other.columns() || rows() != other.rows()DoubleFunctions
public DoubleMatrix2D assign(DoubleMatrix2D y,
DoubleDoubleFunction function,
IntArrayList rowList,
IntArrayList columnList)
y - the secondary matrix to operate on.function - a function object taking as first argument the current cell's
value of this, and as second argument the current
cell's value of y,rowList - row indices.columnList - column indices.
IllegalArgumentException - if
columns() != other.columns() || rows() != other.rows()DoubleFunctionspublic DoubleMatrix2D assign(float[] values)
The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.
values - the values to be filled into the cells.
IllegalArgumentException - if values.length != rows()*columns().public int cardinality()
public DoubleMatrix2D copy()
Note that the returned matrix is an independent deep copy. The returned matrix is not backed by this matrix, so changes in the returned matrix are not reflected in this matrix, and vice-versa.
public abstract void dct2(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dctColumns(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dctRows(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dht2()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dhtColumns()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dhtRows()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dst2(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dstColumns(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void dstRows(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract Object elements()
public boolean equals(double value)
value - the value to test against.
public boolean equals(Object obj)
true if and only if the argument is not null
and is at least a DoubleMatrix2D object that has the same
number of columns and rows as the receiver and has exactly the same
values at the same coordinates.
equals in class Objectobj - the object to compare with.
true if the objects are the same; false
otherwise.public abstract void fft2()
this[k1][2*k2] = Re[k1][k2] = Re[rows-k1][columns-k2],
this[k1][2*k2+1] = Im[k1][k2] = -Im[rows-k1][columns-k2],
0<k1<rows, 0<k2<columns/2,
this[0][2*k2] = Re[0][k2] = Re[0][columns-k2],
this[0][2*k2+1] = Im[0][k2] = -Im[0][columns-k2],
0<k2<columns/2,
this[k1][0] = Re[k1][0] = Re[rows-k1][0],
this[k1][1] = Im[k1][0] = -Im[rows-k1][0],
this[rows-k1][1] = Re[k1][columns/2] = Re[rows-k1][columns/2],
this[rows-k1][0] = -Im[k1][columns/2] = Im[rows-k1][columns/2],
0<k1<rows/2,
this[0][0] = Re[0][0],
this[0][1] = Re[0][columns/2],
this[rows/2][0] = Re[rows/2][0],
this[rows/2][1] = Re[rows/2][columns/2]
This method computes only half of the elements of the real transform. The
other half satisfies the symmetry condition. If you want the full real
forward transform, use getFft2. To get back the original
data, use ifft2.
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public DoubleMatrix2D forEachNonZero(IntIntDoubleFunction function)
function - a function object taking as argument the current non-zero
cell's row, column and value.
public double get(int row,
int column)
row - the index of the row-coordinate.column - the index of the column-coordinate.
IndexOutOfBoundsException - if
column<0 || column>=columns() || row<0 || row>=rows()public abstract DComplexMatrix2D getFft2()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract DComplexMatrix2D getFftColumns()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract DComplexMatrix2D getFftRows()
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract DComplexMatrix2D getIfft2(boolean scale)
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract DComplexMatrix2D getIfftColumns(boolean scale)
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract DComplexMatrix2D getIfftRows(boolean scale)
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.
public void getNegativeValues(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
rowList - the list to be filled with row indexes, can have any size.columnList - the list to be filled with column indexes, can have any size.valueList - the list to be filled with values, can have any size.
public void getNonZeros(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
In general, fill order is unspecified. This implementation fills like for (row = 0..rows-1) for (column = 0..columns-1) do ... . However, subclasses are free to us any other order, even an order that may change over time as cell values are changed. (Of course, result lists indexes are guaranteed to correspond to the same cell).
Example:
2 x 3 matrix:
0, 0, 8
0, 7, 0
-->
rowList = (0,1)
columnList = (2,1)
valueList = (8,7)
In other words, get(0,2)==8, get(1,1)==7.
rowList - the list to be filled with row indexes, can have any size.columnList - the list to be filled with column indexes, can have any size.valueList - the list to be filled with values, can have any size.
public void getPositiveValues(IntArrayList rowList,
IntArrayList columnList,
DoubleArrayList valueList)
rowList - the list to be filled with row indexes, can have any size.columnList - the list to be filled with column indexes, can have any size.valueList - the list to be filled with values, can have any size.
public abstract double getQuick(int row,
int column)
Provided with invalid parameters this method may return invalid objects without throwing any exception. You should only use this method when you are absolutely sure that the coordinate is within bounds. Precondition (unchecked): 0 <= column < columns() && 0 <= row < rows().
row - the index of the row-coordinate.column - the index of the column-coordinate.
public abstract void idct2(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idctColumns(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idctRows(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idht2(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idhtColumns(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idhtRows(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idst2(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idstColumns(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void idstRows(boolean scale)
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public abstract void ifft2(boolean scale)
this[k1][2*k2] = Re[k1][k2] = Re[rows-k1][columns-k2],
this[k1][2*k2+1] = Im[k1][k2] = -Im[rows-k1][columns-k2],
0<k1<rows, 0<k2<columns/2,
this[0][2*k2] = Re[0][k2] = Re[0][columns-k2],
this[0][2*k2+1] = Im[0][k2] = -Im[0][columns-k2],
0<k2<columns/2,
this[k1][0] = Re[k1][0] = Re[rows-k1][0],
this[k1][1] = Im[k1][0] = -Im[rows-k1][0],
this[rows-k1][1] = Re[k1][columns/2] = Re[rows-k1][columns/2],
this[rows-k1][0] = -Im[k1][columns/2] = Im[rows-k1][columns/2],
0<k1<rows/2,
this[0][0] = Re[0][0],
this[0][1] = Re[0][columns/2],
this[rows/2][0] = Re[rows/2][0],
this[rows/2][1] = Re[rows/2][columns/2]
This method computes only half of the elements of the real transform. The
other half satisfies the symmetry condition. If you want the full real
inverse transform, use getIfft2.
scale - if true then scaling is performed
IllegalArgumentException - if the row size or the column size of this matrix is not a
power of 2 number.public DoubleMatrix2D like()
public abstract DoubleMatrix2D like(int rows,
int columns)
rows - the number of rows the matrix shall have.columns - the number of columns the matrix shall have.
public abstract DoubleMatrix1D like1D(int size)
size - the number of cells the matrix shall have.
public double[] getMaxLocation()
public double[] getMinLocation()
public void normalize()
public void set(int row,
int column,
double value)
row - the index of the row-coordinate.column - the index of the column-coordinate.value - the value to be filled into the specified cell.
IndexOutOfBoundsException - if
column<0 || column>=columns() || row<0 || row>=rows()public void setNcolumns(int columns)
columns - public void setNrows(int rows)
rows -
public abstract void setQuick(int row,
int column,
double value)
Provided with invalid parameters this method may access illegal indexes without throwing any exception. You should only use this method when you are absolutely sure that the coordinate is within bounds. Precondition (unchecked): 0 <= column < columns() && 0 <= row < rows().
row - the index of the row-coordinate.column - the index of the column-coordinate.value - the value to be filled into the specified cell.public double[][] toArray()
The values are copied. So subsequent changes in values are not reflected in the matrix, and vice-versa.
public String toString()
toString in class ObjectDoubleFormatterpublic abstract DoubleMatrix1D vectorize()
public DoubleMatrix1D viewColumn(int column)
Example:
| 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
viewColumn(0) ==> | Matrix1D of size 2: 1, 4 |
column - the column to fix.
IndexOutOfBoundsException - if column < 0 || column >= columns().viewRow(int)public DoubleMatrix2D viewColumnFlip()
Example:
| 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
columnFlip ==> | 2 x 3 matrix: 3, 2, 1 6, 5, 4 |
columnFlip ==> | 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
viewRowFlip()public DoubleMatrix2D viewDice()
Example:
| 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
transpose ==> | 3 x 2 matrix: 1, 4 2, 5 3, 6 |
transpose ==> | 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
public DoubleMatrix2D viewPart(int row,
int column,
int height,
int width)
Note that the view is really just a range restriction: The returned matrix is backed by this matrix, so changes in the returned matrix are reflected in this matrix, and vice-versa.
The view contains the cells from [row,column] to [row+height-1,column+width-1], all inclusive. and has view.rows() == height; view.columns() == width;. A view's legal coordinates are again zero based, as usual. In other words, legal coordinates of the view range from [0,0] to [view.rows()-1==height-1,view.columns()-1==width-1]. As usual, any attempt to access a cell at a coordinate column<0 || column>=view.columns() || row<0 || row>=view.rows() will throw an IndexOutOfBoundsException.
row - The index of the row-coordinate.column - The index of the column-coordinate.height - The height of the box.width - The width of the box.
IndexOutOfBoundsException - if
column<0 || width<0 || column+width>columns() || row<0 || height<0 || row+height>rows()public DoubleMatrix1D viewRow(int row)
Example:
| 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
viewRow(0) ==> | Matrix1D of size 3: 1, 2, 3 |
row - the row to fix.
IndexOutOfBoundsException - if row < 0 || row >= rows().viewColumn(int)public DoubleMatrix2D viewRowFlip()
Example:
| 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
rowFlip ==> | 2 x 3 matrix: 4, 5, 6 1, 2, 3 |
rowFlip ==> | 2 x 3 matrix: 1, 2, 3 4, 5, 6 |
viewColumnFlip()public DoubleMatrix2D viewSelection(DoubleMatrix1DProcedure condition)
Example:
// extract and view all rows which have a value < threshold in the first column (representing "age")
final double threshold = 16;
matrix.viewSelection(
new DoubleMatrix1DProcedure() {
public final boolean apply(DoubleMatrix1D m) { return m.get(0) < threshold; }
}
);
// extract and view all rows with RMS < threshold
// The RMS (Root-Mean-Square) is a measure of the average "size" of the elements of a data sequence.
matrix = 0 1 2 3
final double threshold = 0.5;
matrix.viewSelection(
new DoubleMatrix1DProcedure() {
public final boolean apply(DoubleMatrix1D m) { return Math.sqrt(m.aggregate(F.plus,F.square) / m.size()) < threshold; }
}
);
For further examples, see the package doc. The returned
view is backed by this matrix, so changes in the returned view are
reflected in this matrix, and vice-versa.
condition - The condition to be matched.
public DoubleMatrix2D viewSelection(int[] rowIndexes,
int[] columnIndexes)
Example:
this = 2 x 3 matrix:
1, 2, 3
4, 5, 6
rowIndexes = (0,1)
columnIndexes = (1,0,1,0)
-->
view = 2 x 4 matrix:
2, 1, 2, 1
5, 4, 5, 4
Note that modifying the index arguments after this call has returned has
no effect on the view. The returned view is backed by this matrix, so
changes in the returned view are reflected in this matrix, and
vice-versa.
To indicate "all" rows or "all columns", simply set the respective parameter
rowIndexes - The rows of the cells that shall be visible in the new view.
To indicate that all rows shall be visible, simply set
this parameter to null.columnIndexes - The columns of the cells that shall be visible in the new
view. To indicate that all columns shall be visible,
simply set this parameter to null.
IndexOutOfBoundsException - if !(0 <= rowIndexes[i] < rows()) for any
i=0..rowIndexes.length()-1.
IndexOutOfBoundsException - if !(0 <= columnIndexes[i] < columns()) for any
i=0..columnIndexes.length()-1.public DoubleMatrix2D viewSelection(Set<int[]> indexes)
public DoubleMatrix2D viewSorted(int column)
DoubleSorting.sort(DoubleMatrix2D,int). For
more advanced sorting functionality, see