public class SparseMatrix extends java.lang.Object implements Matrix
1.0 0.0 4.0
0.0 3.0 5.0
2.0 0.0 6.0
is stored as values: [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]
,
rowIndices=[0, 2, 1, 0, 1, 2]
, colPointers=[0, 2, 3, 6]
.
param: numRows number of rows
param: numCols number of columns
param: colPtrs the index corresponding to the start of a new column (if not transposed)
param: rowIndices the row index of the entry (if not transposed). They must be in strictly
increasing order for each column
param: values nonzero matrix entries in column major (if not transposed)
param: isTransposed whether the matrix is transposed. If true, the matrix can be considered
Compressed Sparse Row (CSR) format, where colPtrs
behaves as rowPtrs,
and rowIndices
behave as colIndices, and values
are stored in row major.
Constructor and Description |
---|
SparseMatrix(int numRows,
int numCols,
int[] colPtrs,
int[] rowIndices,
double[] values)
Column-major sparse matrix.
|
SparseMatrix(int numRows,
int numCols,
int[] colPtrs,
int[] rowIndices,
double[] values,
boolean isTransposed) |
Modifier and Type | Method and Description |
---|---|
double |
apply(int i,
int j)
Gets the (i, j)-th element.
|
scala.collection.Iterator<Vector> |
colIter()
Returns an iterator of column vectors.
|
int[] |
colPtrs() |
SparseMatrix |
copy()
Get a deep copy of the matrix.
|
boolean |
equals(java.lang.Object o) |
static SparseMatrix |
fromCOO(int numRows,
int numCols,
scala.collection.Iterable<scala.Tuple3<java.lang.Object,java.lang.Object,java.lang.Object>> entries)
Generate a
SparseMatrix from Coordinate List (COO) format. |
int |
hashCode() |
boolean |
isTransposed()
Flag that keeps track whether the matrix is transposed or not.
|
static DenseMatrix |
multiply(DenseMatrix y) |
static DenseVector |
multiply(DenseVector y) |
static DenseVector |
multiply(Vector y) |
int |
numActives()
Find the number of values stored explicitly.
|
int |
numCols()
Number of columns.
|
int |
numNonzeros()
Find the number of non-zero active values.
|
int |
numRows()
Number of rows.
|
int[] |
rowIndices() |
static scala.collection.Iterator<Vector> |
rowIter() |
static SparseMatrix |
spdiag(Vector vector)
Generate a diagonal matrix in
SparseMatrix format from the supplied values. |
static SparseMatrix |
speye(int n)
Generate an Identity Matrix in
SparseMatrix format. |
static SparseMatrix |
sprand(int numRows,
int numCols,
double density,
java.util.Random rng)
Generate a
SparseMatrix consisting of i.i.d . |
static SparseMatrix |
sprandn(int numRows,
int numCols,
double density,
java.util.Random rng)
Generate a
SparseMatrix consisting of i.i.d . |
static double[] |
toArray() |
DenseMatrix |
toDense()
Generate a
DenseMatrix from the given SparseMatrix . |
static java.lang.String |
toString() |
static java.lang.String |
toString(int maxLines,
int maxLineWidth) |
SparseMatrix |
transpose()
Transpose the Matrix.
|
double[] |
values() |
public SparseMatrix(int numRows, int numCols, int[] colPtrs, int[] rowIndices, double[] values, boolean isTransposed)
public SparseMatrix(int numRows, int numCols, int[] colPtrs, int[] rowIndices, double[] values)
1.0 0.0 4.0
0.0 3.0 5.0
2.0 0.0 6.0
is stored as values: [1.0, 2.0, 3.0, 4.0, 5.0, 6.0]
,
rowIndices=[0, 2, 1, 0, 1, 2]
, colPointers=[0, 2, 3, 6]
.
numRows
- number of rowsnumCols
- number of columnscolPtrs
- the index corresponding to the start of a new columnrowIndices
- the row index of the entry. They must be in strictly increasing
order for each columnvalues
- non-zero matrix entries in column majorpublic static SparseMatrix fromCOO(int numRows, int numCols, scala.collection.Iterable<scala.Tuple3<java.lang.Object,java.lang.Object,java.lang.Object>> entries)
SparseMatrix
from Coordinate List (COO) format. Input must be an array of
(i, j, value) tuples. Entries that have duplicate values of i and j are
added together. Tuples where value is equal to zero will be omitted.numRows
- number of rows of the matrixnumCols
- number of columns of the matrixentries
- Array of (i, j, value) tuplesSparseMatrix
public static SparseMatrix speye(int n)
SparseMatrix
format.n
- number of rows and columns of the matrixSparseMatrix
with size n
x n
and values of ones on the diagonalpublic static SparseMatrix sprand(int numRows, int numCols, double density, java.util.Random rng)
SparseMatrix
consisting of i.i.d
. uniform random numbers. The number of non-zero
elements equal the ceiling of numRows
x numCols
x density
numRows
- number of rows of the matrixnumCols
- number of columns of the matrixdensity
- the desired density for the matrixrng
- a random number generatorSparseMatrix
with size numRows
x numCols
and values in U(0, 1)public static SparseMatrix sprandn(int numRows, int numCols, double density, java.util.Random rng)
SparseMatrix
consisting of i.i.d
. gaussian random numbers.numRows
- number of rows of the matrixnumCols
- number of columns of the matrixdensity
- the desired density for the matrixrng
- a random number generatorSparseMatrix
with size numRows
x numCols
and values in N(0, 1)public static SparseMatrix spdiag(Vector vector)
SparseMatrix
format from the supplied values.vector
- a Vector
that will form the values on the diagonal of the matrixSparseMatrix
with size values.length
x values.length
and non-zero
values
on the diagonalpublic static double[] toArray()
public static scala.collection.Iterator<Vector> rowIter()
public static DenseMatrix multiply(DenseMatrix y)
public static DenseVector multiply(DenseVector y)
public static DenseVector multiply(Vector y)
public static java.lang.String toString()
public static java.lang.String toString(int maxLines, int maxLineWidth)
public int numRows()
Matrix
public int numCols()
Matrix
public int[] colPtrs()
public int[] rowIndices()
public double[] values()
public boolean isTransposed()
Matrix
isTransposed
in interface Matrix
public int hashCode()
hashCode
in class java.lang.Object
public boolean equals(java.lang.Object o)
equals
in class java.lang.Object
public double apply(int i, int j)
Matrix
public SparseMatrix copy()
Matrix
public SparseMatrix transpose()
Matrix
public DenseMatrix toDense()
DenseMatrix
from the given SparseMatrix
. The new matrix will have isTransposed
set to false.public int numNonzeros()
Matrix
numNonzeros
in interface Matrix
public int numActives()
Matrix
numActives
in interface Matrix