cupyx.scipy.sparse.coo_matrix#
- class cupyx.scipy.sparse.coo_matrix(arg1, shape=None, dtype=None, copy=False)[source]#
COOrdinate format sparse matrix.
This can be instantiated in several ways.
coo_matrix(D)
D
is a rank-2cupy.ndarray
.coo_matrix(S)
S
is another sparse matrix. It is equivalent toS.tocoo()
.coo_matrix((M, N), [dtype])
It constructs an empty matrix whose shape is
(M, N)
. Default dtype is float64.coo_matrix((data, (row, col)))
All
data
,row
andcol
are one-dimenaionalcupy.ndarray
.
- Parameters
arg1 – Arguments for the initializer.
shape (tuple) – Shape of a matrix. Its length must be two.
dtype – Data type. It must be an argument of
numpy.dtype
.copy (bool) – If
True
, copies of given data are always used.
See also
Methods
- asformat(format)[source]#
Return this matrix in a given sparse format.
- Parameters
format (str or None) – Format you need.
- asfptype()[source]#
Upcasts matrix to a floating point format.
When the matrix has floating point type, the method returns itself. Otherwise it makes a copy with floating point type and the same format.
- Returns
A matrix with float type.
- Return type
- astype(t)[source]#
Casts the array to given data type.
- Parameters
dtype – Type specifier.
- Returns
A copy of the array with a given type.
- conj(copy=True)[source]#
Element-wise complex conjugation.
If the matrix is of non-complex data type and copy is False, this method does nothing and the data is not copied.
- Parameters
copy (bool) – If True, the result is guaranteed to not share data with self.
- Returns
The element-wise complex conjugate.
- Return type
- conjugate(copy=True)[source]#
Element-wise complex conjugation.
If the matrix is of non-complex data type and copy is False, this method does nothing and the data is not copied.
- Parameters
copy (bool) – If True, the result is guaranteed to not share data with self.
- Returns
The element-wise complex conjugate.
- Return type
- copy()[source]#
Returns a copy of this matrix.
No data/indices will be shared between the returned value and current matrix.
- count_nonzero()[source]#
Returns number of non-zero entries.
Note
This method counts the actual number of non-zero entories, which does not include explicit zero entries. Instead
nnz
returns the number of entries including explicit zeros.- Returns
Number of non-zero entries.
- diagonal(k=0)[source]#
Returns the k-th diagonal of the matrix.
- Parameters
k (int, optional) – Which diagonal to get, corresponding to elements
a[i – 0 (the main diagonal).
Default (i+k].) – 0 (the main diagonal).
- Returns
The k-th diagonal.
- Return type
- get(stream=None)[source]#
Returns a copy of the array on host memory.
- Parameters
stream (cupy.cuda.Stream) – CUDA stream object. If it is given, the copy runs asynchronously. Otherwise, the copy is synchronous.
- Returns
Copy of the array on host memory.
- Return type
- mean(axis=None, dtype=None, out=None)[source]#
Compute the arithmetic mean along the specified axis.
- Parameters
axis (int or
None
) – Axis along which the sum is computed. If it isNone
, it computes the average of all the elements. Select from{None, 0, 1, -2, -1}
.- Returns
Summed array.
- Return type
See also
scipy.sparse.spmatrix.mean()
- power(n, dtype=None)[source]#
Elementwise power function.
- Parameters
n – Exponent.
dtype – Type specifier.
- reshape(*shape, order='C')[source]#
Gives a new shape to a sparse matrix without changing its data.
- Parameters
shape (tuple) – The new shape should be compatible with the original shape.
order – {‘C’, ‘F’} (optional) Read the elements using this index order. ‘C’ means to read and write the elements using C-like index order. ‘F’ means to read and write the elements using Fortran-like index order. Default: C.
- Returns
sparse matrix
- Return type
- setdiag(values, k=0)[source]#
Set diagonal or off-diagonal elements of the array.
- Parameters
values (ndarray) – New values of the diagonal elements. Values may have any length. If the diagonal is longer than values, then the remaining diagonal entries will not be set. If values are longer than the diagonal, then the remaining values are ignored. If a scalar value is given, all of the diagonal is set to it.
k (int, optional) – Which off-diagonal to set, corresponding to elements a[i,i+k]. Default: 0 (the main diagonal).
- sum(axis=None, dtype=None, out=None)[source]#
Sums the matrix elements over a given axis.
- Parameters
axis (int or
None
) – Axis along which the sum is comuted. If it isNone
, it computes the sum of all the elements. Select from{None, 0, 1, -2, -1}
.dtype – The type of returned matrix. If it is not specified, type of the array is used.
out (cupy.ndarray) – Output matrix.
- Returns
Summed array.
- Return type
See also
scipy.sparse.spmatrix.sum()
- sum_duplicates()[source]#
Eliminate duplicate matrix entries by adding them together.
Warning
When sorting the indices, CuPy follows the convention of cuSPARSE, which is different from that of SciPy. Therefore, the order of the output indices may differ:
>>> # 1 0 0 >>> # A = 1 1 0 >>> # 1 1 1 >>> data = cupy.array([1, 1, 1, 1, 1, 1], 'f') >>> row = cupy.array([0, 1, 1, 2, 2, 2], 'i') >>> col = cupy.array([0, 0, 1, 0, 1, 2], 'i') >>> A = cupyx.scipy.sparse.coo_matrix((data, (row, col)), ... shape=(3, 3)) >>> a = A.get() >>> A.sum_duplicates() >>> a.sum_duplicates() # a is scipy.sparse.coo_matrix >>> A.row array([0, 1, 1, 2, 2, 2], dtype=int32) >>> a.row array([0, 1, 2, 1, 2, 2], dtype=int32) >>> A.col array([0, 0, 1, 0, 1, 2], dtype=int32) >>> a.col array([0, 0, 0, 1, 1, 2], dtype=int32)
Warning
Calling this function might synchronize the device.
- toarray(order=None, out=None)[source]#
Returns a dense matrix representing the same value.
- Parameters
order (str) – Not supported.
out – Not supported.
- Returns
Dense array representing the same value.
- Return type
See also
- tocoo(copy=False)[source]#
Converts the matrix to COOdinate format.
- Parameters
copy (bool) – If
False
, it shares data arrays as much as possible.- Returns
Converted matrix.
- Return type
- tocsc(copy=False)[source]#
Converts the matrix to Compressed Sparse Column format.
- Parameters
copy (bool) – If
False
, it shares data arrays as much as possible. Actually this option is ignored because all arrays in a matrix cannot be shared in coo to csc conversion.- Returns
Converted matrix.
- Return type
- tocsr(copy=False)[source]#
Converts the matrix to Compressed Sparse Row format.
- Parameters
copy (bool) – If
False
, it shares data arrays as much as possible. Actually this option is ignored because all arrays in a matrix cannot be shared in coo to csr conversion.- Returns
Converted matrix.
- Return type
- transpose(axes=None, copy=False)[source]#
Returns a transpose matrix.
- Parameters
axes – This option is not supported.
copy (bool) – If
True
, a returned matrix shares no data. Otherwise, it shared data arrays as much as possible.
- Returns
Transpose matrix.
- Return type
Attributes
- H#
- T#
- device#
CUDA device on which this array resides.
- dtype#
Data type of the matrix.
- format = 'coo'#
- ndim#
- nnz#
- shape#
- size#