public class SparseDoubleMatrix3D extends DoubleMatrix3D
Implementation:
Note that this implementation is not synchronized. Uses a
OpenIntDoubleHashMap, which is a compact and
performant hashing technique.
Memory requirements:
Cells that
trimToSize().
worst case: memory [bytes] = (1/minLoadFactor) * nonZeros * 13.
best case: memory [bytes] = (1/maxLoadFactor) * nonZeros * 13.
Where nonZeros = cardinality() is the number of non-zero cells.
Thus, a 100 x 100 x 100 matrix with minLoadFactor=0.25 and maxLoadFactor=0.5
and 1000000 non-zero cells consumes between 25 MB and 50 MB. The same 100 x
100 x 100 matrix with 1000 non-zero cells consumes between 25 and 50 KB.
Time complexity:
This class offers expected time complexity O(1) (i.e.
constant time) for the basic operations get, getQuick,
set, setQuick and size assuming the hash function
disperses the elements properly among the buckets. Otherwise, pathological
cases, although highly improbable, can occur, degrading performance to
O(N) in the worst case. As such this sparse class is expected to
have no worse time complexity than its dense counterpart
DenseDoubleMatrix2D. However, constant factors are considerably
larger.
Cells are internally addressed in (in decreasing order of significance): slice major, row major, column major. Applications demanding utmost speed can exploit this fact. Setting/getting values in a loop slice-by-slice, row-by-row, column-by-column is quicker than, for example, column-by-column, row-by-row, slice-by-slice. Thus
for (int slice = 0; slice < slices; slice++) {
for (int row = 0; row < rows; row++) {
for (int column = 0; column < columns; column++) {
matrix.setQuick(slice, row, column, someValue);
}
}
}
is quicker than
for (int column = 0; column < columns; column++) {
for (int row = 0; row < rows; row++) {
for (int slice = 0; slice < slices; slice++) {
matrix.setQuick(slice, row, column, someValue);
}
}
}
cern.colt.map,
OpenIntDoubleHashMap,
Serialized Form| Constructor and Description |
|---|
SparseDoubleMatrix3D(double[][][] values)
Constructs a matrix with a copy of the given values.
|
SparseDoubleMatrix3D(int slices,
int rows,
int columns)
Constructs a matrix with a given number of slices, rows and columns and
default memory usage.
|
SparseDoubleMatrix3D(int slices,
int rows,
int columns,
int initialCapacity,
double minLoadFactor,
double maxLoadFactor)
Constructs a matrix with a given number of slices, rows and columns using
memory as specified.
|
| Modifier and Type | Method and Description |
|---|---|
DoubleMatrix3D |
assign(double value)
Sets all cells to the state specified by value.
|
int |
cardinality()
Returns the number of cells having non-zero values; ignores tolerance.
|
AbstractLongDoubleMap |
elements()
Returns the elements of this matrix.
|
void |
ensureCapacity(int minCapacity)
Ensures that the receiver can hold at least the specified number of
non-zero (non-null) cells without needing to allocate new internal
memory.
|
double |
getQuick(int slice,
int row,
int column)
Returns the matrix cell value at coordinate [slice,row,column].
|
long |
index(int slice,
int row,
int column)
Returns the position of the given coordinate within the (virtual or
non-virtual) internal 1-dimensional array.
|
DoubleMatrix3D |
like(int slices,
int rows,
int columns)
Construct and returns a new empty matrix of the same dynamic type
as the receiver, having the specified number of slices, rows and columns.
|
DoubleMatrix2D |
like2D(int rows,
int columns)
Construct and returns a new 2-d matrix of the corresponding dynamic
type, sharing the same cells.
|
void |
setQuick(int slice,
int row,
int column,
double value)
Sets the matrix cell at coordinate [slice,row,column] to the
specified value.
|
String |
toString()
Returns a string representation using default formatting.
|
void |
trimToSize()
Releases any superfluous internal memory.
|
DoubleMatrix1D |
vectorize()
Returns a vector obtained by stacking the columns of each slice of the
matrix on top of one another.
|
aggregate, aggregate, aggregate, aggregate, assign, assign, assign, assign, assign, assign, assign, assign, copy, equals, equals, get, getMaxLocation, getMinLocation, getNegativeValues, getNonZeros, getPositiveValues, like, normalize, set, toArray, viewColumn, viewColumnFlip, viewDice, viewPart, viewRow, viewRowFlip, viewSelection, viewSelection, viewSlice, viewSliceFlip, viewSorted, viewStrides, zAssign27Neighbors, zSumcheckShape, checkShape, columns, columnStride, rows, rowStride, size, slices, sliceStride, toStringShortisViewclonepublic SparseDoubleMatrix3D(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 new matrix.IllegalArgumentException - if
for any 1 <= slice < values.length: values[slice].length != values[slice-1].length
.IllegalArgumentException - if
for any 1 <= row < values[0].length: values[slice][row].length != values[slice][row-1].length
.public SparseDoubleMatrix3D(int slices,
int rows,
int columns)
slices - the number of slices the matrix shall have.rows - the number of rows the matrix shall have.columns - the number of columns the matrix shall have.IllegalArgumentException - if (double)slices*columns*rows > Integer.MAX_VALUE.IllegalArgumentException - if slices<0 || rows<0 || columns<0.public SparseDoubleMatrix3D(int slices,
int rows,
int columns,
int initialCapacity,
double minLoadFactor,
double maxLoadFactor)
OpenIntDoubleHashMap.slices - the number of slices the matrix shall have.rows - the number of rows the matrix shall have.columns - the number of columns the matrix shall have.initialCapacity - the initial capacity of the hash map. If not known, set
initialCapacity=0 or small.minLoadFactor - the minimum load factor of the hash map.maxLoadFactor - the maximum load factor of the hash map.IllegalArgumentException - if
initialCapacity < 0 || (minLoadFactor < 0.0 || minLoadFactor >= 1.0) || (maxLoadFactor <= 0.0 || maxLoadFactor >= 1.0) || (minLoadFactor >= maxLoadFactor)
.IllegalArgumentException - if (double)columns*rows > Integer.MAX_VALUE.IllegalArgumentException - if slices<0 || rows<0 || columns<0.public DoubleMatrix3D assign(double value)
DoubleMatrix3Dassign in class DoubleMatrix3Dvalue - the value to be filled into the cells.public int cardinality()
DoubleMatrix3Dcardinality in class DoubleMatrix3Dpublic AbstractLongDoubleMap elements()
DoubleMatrix3Delements in class DoubleMatrix3Dpublic void ensureCapacity(int minCapacity)
AbstractMatrixThis default implementation does nothing. Override this method if necessary.
ensureCapacity in class AbstractMatrixminCapacity - the desired minimum number of non-zero (non-null) cells.public double getQuick(int slice,
int row,
int column)
DoubleMatrix3DProvided 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): slice<0 || slice>=slices() || row<0 || row>=rows() || column<0 || column>=column().
getQuick in class DoubleMatrix3Dslice - the index of the slice-coordinate.row - the index of the row-coordinate.column - the index of the column-coordinate.public long index(int slice,
int row,
int column)
AbstractMatrix3Dindex in class AbstractMatrix3Dslice - the index of the slice-coordinate.row - the index of the row-coordinate.column - the index of the third-coordinate.public DoubleMatrix3D like(int slices, int rows, int columns)
DoubleMatrix3Dlike in class DoubleMatrix3Dslices - the number of slices the matrix shall have.rows - the number of rows the matrix shall have.columns - the number of columns the matrix shall have.public DoubleMatrix2D like2D(int rows, int columns)
DoubleMatrix3Dlike2D in class DoubleMatrix3Drows - the number of rows the matrix shall have.columns - the number of columns the matrix shall have.public void setQuick(int slice,
int row,
int column,
double value)
DoubleMatrix3DProvided 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): slice<0 || slice>=slices() || row<0 || row>=rows() || column<0 || column>=column().
setQuick in class DoubleMatrix3Dslice - the index of the slice-coordinate.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 String toString()
DoubleMatrix3DtoString in class DoubleMatrix3DDoubleFormatterpublic void trimToSize()
AbstractMatrixThis default implementation does nothing. Override this method if necessary.
trimToSize in class AbstractMatrixpublic DoubleMatrix1D vectorize()
DoubleMatrix3Dvectorize in class DoubleMatrix3DJump to the Parallel Colt Homepage