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from collections import defaultdict
from sympy.core import SympifyError, Add
from sympy.core.compatibility import Callable, as_int, is_sequence, reduce
from sympy.core.containers import Dict
from sympy.core.expr import Expr
from sympy.core.singleton import S
from sympy.functions import Abs
from sympy.utilities.iterables import uniq
from .common import a2idx
from .dense import Matrix
from .matrices import MatrixBase, ShapeError
from .utilities import _iszero
from .decompositions import (
_liupc, _row_structure_symbolic_cholesky, _cholesky_sparse,
_LDLdecomposition_sparse)
from .solvers import (
_lower_triangular_solve_sparse, _upper_triangular_solve_sparse)
class SparseMatrix(MatrixBase):
"""
A sparse matrix (a matrix with a large number of zero elements).
Examples
========
>>> from sympy.matrices import SparseMatrix, ones
>>> SparseMatrix(2, 2, range(4))
Matrix([
[0, 1],
[2, 3]])
>>> SparseMatrix(2, 2, {(1, 1): 2})
Matrix([
[0, 0],
[0, 2]])
A SparseMatrix can be instantiated from a ragged list of lists:
>>> SparseMatrix([[1, 2, 3], [1, 2], [1]])
Matrix([
[1, 2, 3],
[1, 2, 0],
[1, 0, 0]])
For safety, one may include the expected size and then an error
will be raised if the indices of any element are out of range or
(for a flat list) if the total number of elements does not match
the expected shape:
>>> SparseMatrix(2, 2, [1, 2])
Traceback (most recent call last):
...
ValueError: List length (2) != rows*columns (4)
Here, an error is not raised because the list is not flat and no
element is out of range:
>>> SparseMatrix(2, 2, [[1, 2]])
Matrix([
[1, 2],
[0, 0]])
But adding another element to the first (and only) row will cause
an error to be raised:
>>> SparseMatrix(2, 2, [[1, 2, 3]])
Traceback (most recent call last):
...
ValueError: The location (0, 2) is out of designated range: (1, 1)
To autosize the matrix, pass None for rows:
>>> SparseMatrix(None, [[1, 2, 3]])
Matrix([[1, 2, 3]])
>>> SparseMatrix(None, {(1, 1): 1, (3, 3): 3})
Matrix([
[0, 0, 0, 0],
[0, 1, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 3]])
Values that are themselves a Matrix are automatically expanded:
>>> SparseMatrix(4, 4, {(1, 1): ones(2)})
Matrix([
[0, 0, 0, 0],
[0, 1, 1, 0],
[0, 1, 1, 0],
[0, 0, 0, 0]])
A ValueError is raised if the expanding matrix tries to overwrite
a different element already present:
>>> SparseMatrix(3, 3, {(0, 0): ones(2), (1, 1): 2})
Traceback (most recent call last):
...
ValueError: collision at (1, 1)
See Also
========
DenseMatrix
MutableSparseMatrix
ImmutableSparseMatrix
"""
@classmethod
def _handle_creation_inputs(cls, *args, **kwargs):
if len(args) == 1 and isinstance(args[0], MatrixBase):
rows = args[0].rows
cols = args[0].cols
smat = args[0].todok()
return rows, cols, smat
smat = {}
# autosizing
if len(args) == 2 and args[0] is None:
args = [None, None, args[1]]
if len(args) == 3:
r, c = args[:2]
if r is c is None:
rows = cols = None
elif None in (r, c):
raise ValueError(
'Pass rows=None and no cols for autosizing.')
else:
rows, cols = as_int(args[0]), as_int(args[1])
if isinstance(args[2], Callable):
op = args[2]
if None in (rows, cols):
raise ValueError(
"{} and {} must be integers for this "
"specification.".format(rows, cols))
row_indices = [cls._sympify(i) for i in range(rows)]
col_indices = [cls._sympify(j) for j in range(cols)]
for i in row_indices:
for j in col_indices:
value = cls._sympify(op(i, j))
if value != cls.zero:
smat[i, j] = value
return rows, cols, smat
elif isinstance(args[2], (dict, Dict)):
def update(i, j, v):
# update self._smat and make sure there are
# no collisions
if v:
if (i, j) in smat and v != smat[i, j]:
raise ValueError(
"There is a collision at {} for {} and {}."
.format((i, j), v, smat[i, j])
)
smat[i, j] = v
# manual copy, copy.deepcopy() doesn't work
for (r, c), v in args[2].items():
if isinstance(v, MatrixBase):
for (i, j), vv in v.todok().items():
update(r + i, c + j, vv)
elif isinstance(v, (list, tuple)):
_, _, smat = cls._handle_creation_inputs(v, **kwargs)
for i, j in smat:
update(r + i, c + j, smat[i, j])
else:
v = cls._sympify(v)
update(r, c, cls._sympify(v))
elif is_sequence(args[2]):
flat = not any(is_sequence(i) for i in args[2])
if not flat:
_, _, smat = \
cls._handle_creation_inputs(args[2], **kwargs)
else:
flat_list = args[2]
if len(flat_list) != rows * cols:
raise ValueError(
"The length of the flat list ({}) does not "
"match the specified size ({} * {})."
.format(len(flat_list), rows, cols)
)
for i in range(rows):
for j in range(cols):
value = flat_list[i*cols + j]
value = cls._sympify(value)
if value != cls.zero:
smat[i, j] = value
if rows is None: # autosizing
keys = smat.keys()
rows = max([r for r, _ in keys]) + 1 if keys else 0
cols = max([c for _, c in keys]) + 1 if keys else 0
else:
for i, j in smat.keys():
if i and i >= rows or j and j >= cols:
raise ValueError(
"The location {} is out of the designated range"
"[{}, {}]x[{}, {}]"
.format((i, j), 0, rows - 1, 0, cols - 1)
)
return rows, cols, smat
elif len(args) == 1 and isinstance(args[0], (list, tuple)):
# list of values or lists
v = args[0]
c = 0
for i, row in enumerate(v):
if not isinstance(row, (list, tuple)):
row = [row]
for j, vv in enumerate(row):
if vv != cls.zero:
smat[i, j] = cls._sympify(vv)
c = max(c, len(row))
rows = len(v) if c else 0
cols = c
return rows, cols, smat
else:
# handle full matrix forms with _handle_creation_inputs
rows, cols, mat = super()._handle_creation_inputs(*args)
for i in range(rows):
for j in range(cols):
value = mat[cols*i + j]
if value != cls.zero:
smat[i, j] = value
return rows, cols, smat
def __eq__(self, other):
self_shape = getattr(self, 'shape', None)
other_shape = getattr(other, 'shape', None)
if None in (self_shape, other_shape):
return False
if self_shape != other_shape:
return False
if isinstance(other, SparseMatrix):
return self._smat == other._smat
elif isinstance(other, MatrixBase):
return self._smat == MutableSparseMatrix(other)._smat
def __getitem__(self, key):
if isinstance(key, tuple):
i, j = key
try:
i, j = self.key2ij(key)
return self._smat.get((i, j), S.Zero)
except (TypeError, IndexError):
if isinstance(i, slice):
i = range(self.rows)[i]
elif is_sequence(i):
pass
elif isinstance(i, Expr) and not i.is_number:
from sympy.matrices.expressions.matexpr import MatrixElement
return MatrixElement(self, i, j)
else:
if i >= self.rows:
raise IndexError('Row index out of bounds')
i = [i]
if isinstance(j, slice):
j = range(self.cols)[j]
elif is_sequence(j):
pass
elif isinstance(j, Expr) and not j.is_number:
from sympy.matrices.expressions.matexpr import MatrixElement
return MatrixElement(self, i, j)
else:
if j >= self.cols:
raise IndexError('Col index out of bounds')
j = [j]
return self.extract(i, j)
# check for single arg, like M[:] or M[3]
if isinstance(key, slice):
lo, hi = key.indices(len(self))[:2]
L = []
for i in range(lo, hi):
m, n = divmod(i, self.cols)
L.append(self._smat.get((m, n), S.Zero))
return L
i, j = divmod(a2idx(key, len(self)), self.cols)
return self._smat.get((i, j), S.Zero)
def __setitem__(self, key, value):
raise NotImplementedError()
def _eval_inverse(self, **kwargs):
return self.inv(method=kwargs.get('method', 'LDL'),
iszerofunc=kwargs.get('iszerofunc', _iszero),
try_block_diag=kwargs.get('try_block_diag', False))
def _eval_Abs(self):
return self.applyfunc(lambda x: Abs(x))
def _eval_add(self, other):
"""If `other` is a SparseMatrix, add efficiently. Otherwise,
do standard addition."""
if not isinstance(other, SparseMatrix):
return self + self._new(other)
smat = {}
zero = self._sympify(0)
for key in set().union(self._smat.keys(), other._smat.keys()):
sum = self._smat.get(key, zero) + other._smat.get(key, zero)
if sum != 0:
smat[key] = sum
return self._new(self.rows, self.cols, smat)
def _eval_col_insert(self, icol, other):
if not isinstance(other, SparseMatrix):
other = MutableSparseMatrix(other)
new_smat = {}
# make room for the new rows
for key, val in self._smat.items():
row, col = key
if col >= icol:
col += other.cols
new_smat[row, col] = val
# add other's keys
for key, val in other._smat.items():
row, col = key
new_smat[row, col + icol] = val
return self._new(self.rows, self.cols + other.cols, new_smat)
def _eval_conjugate(self):
smat = {key: val.conjugate() for key,val in self._smat.items()}
return self._new(self.rows, self.cols, smat)
def _eval_extract(self, rowsList, colsList):
urow = list(uniq(rowsList))
ucol = list(uniq(colsList))
smat = {}
if len(urow)*len(ucol) < len(self._smat):
# there are fewer elements requested than there are elements in the matrix
for i, r in enumerate(urow):
for j, c in enumerate(ucol):
smat[i, j] = self._smat.get((r, c), 0)
else:
# most of the request will be zeros so check all of self's entries,
# keeping only the ones that are desired
for rk, ck in self._smat:
if rk in urow and ck in ucol:
smat[urow.index(rk), ucol.index(ck)] = self._smat[rk, ck]
rv = self._new(len(urow), len(ucol), smat)
# rv is nominally correct but there might be rows/cols
# which require duplication
if len(rowsList) != len(urow):
for i, r in enumerate(rowsList):
i_previous = rowsList.index(r)
if i_previous != i:
rv = rv.row_insert(i, rv.row(i_previous))
if len(colsList) != len(ucol):
for i, c in enumerate(colsList):
i_previous = colsList.index(c)
if i_previous != i:
rv = rv.col_insert(i, rv.col(i_previous))
return rv
@classmethod
def _eval_eye(cls, rows, cols):
entries = {(i,i): S.One for i in range(min(rows, cols))}
return cls._new(rows, cols, entries)
def _eval_has(self, *patterns):
# if the matrix has any zeros, see if S.Zero
# has the pattern. If _smat is full length,
# the matrix has no zeros.
zhas = S.Zero.has(*patterns)
if len(self._smat) == self.rows*self.cols:
zhas = False
return any(self[key].has(*patterns) for key in self._smat) or zhas
def _eval_is_Identity(self):
if not all(self[i, i] == 1 for i in range(self.rows)):
return False
return len(self._smat) == self.rows
def _eval_is_symmetric(self, simpfunc):
diff = (self - self.T).applyfunc(simpfunc)
return len(diff.values()) == 0
def _eval_matrix_mul(self, other):
"""Fast multiplication exploiting the sparsity of the matrix."""
if not isinstance(other, SparseMatrix):
other = self._new(other)
# if we made it here, we're both sparse matrices
# create quick lookups for rows and cols
row_lookup = defaultdict(dict)
for (i,j), val in self._smat.items():
row_lookup[i][j] = val
col_lookup = defaultdict(dict)
for (i,j), val in other._smat.items():
col_lookup[j][i] = val
smat = {}
for row in row_lookup.keys():
for col in col_lookup.keys():
# find the common indices of non-zero entries.
# these are the only things that need to be multiplied.
indices = set(col_lookup[col].keys()) & set(row_lookup[row].keys())
if indices:
vec = [row_lookup[row][k]*col_lookup[col][k] for k in indices]
try:
smat[row, col] = Add(*vec)
except (TypeError, SympifyError):
# Some matrices don't work with `sum` or `Add`
# They don't work with `sum` because `sum` tries to add `0`
# Fall back to a safe way to multiply if the `Add` fails.
smat[row, col] = reduce(lambda a, b: a + b, vec)
return self._new(self.rows, other.cols, smat)
def _eval_row_insert(self, irow, other):
if not isinstance(other, SparseMatrix):
other = MutableSparseMatrix(other)
new_smat = {}
# make room for the new rows
for key, val in self._smat.items():
row, col = key
if row >= irow:
row += other.rows
new_smat[row, col] = val
# add other's keys
for key, val in other._smat.items():
row, col = key
new_smat[row + irow, col] = val
return self._new(self.rows + other.rows, self.cols, new_smat)
def _eval_scalar_mul(self, other):
return self.applyfunc(lambda x: x*other)
def _eval_scalar_rmul(self, other):
return self.applyfunc(lambda x: other*x)
def _eval_todok(self):
return self._smat.copy()
def _eval_transpose(self):
"""Returns the transposed SparseMatrix of this SparseMatrix.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> a = SparseMatrix(((1, 2), (3, 4)))
>>> a
Matrix([
[1, 2],
[3, 4]])
>>> a.T
Matrix([
[1, 3],
[2, 4]])
"""
smat = {(j,i): val for (i,j),val in self._smat.items()}
return self._new(self.cols, self.rows, smat)
def _eval_values(self):
return [v for k,v in self._smat.items() if not v.is_zero]
@classmethod
def _eval_zeros(cls, rows, cols):
return cls._new(rows, cols, {})
@property
def _mat(self):
"""Return a list of matrix elements. Some routines
in DenseMatrix use `_mat` directly to speed up operations."""
return list(self)
def applyfunc(self, f):
"""Apply a function to each element of the matrix.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> m = SparseMatrix(2, 2, lambda i, j: i*2+j)
>>> m
Matrix([
[0, 1],
[2, 3]])
>>> m.applyfunc(lambda i: 2*i)
Matrix([
[0, 2],
[4, 6]])
"""
if not callable(f):
raise TypeError("`f` must be callable.")
out = self.copy()
for k, v in self._smat.items():
fv = f(v)
if fv:
out._smat[k] = fv
else:
out._smat.pop(k, None)
return out
def as_immutable(self):
"""Returns an Immutable version of this Matrix."""
from .immutable import ImmutableSparseMatrix
return ImmutableSparseMatrix(self)
def as_mutable(self):
"""Returns a mutable version of this matrix.
Examples
========
>>> from sympy import ImmutableMatrix
>>> X = ImmutableMatrix([[1, 2], [3, 4]])
>>> Y = X.as_mutable()
>>> Y[1, 1] = 5 # Can set values in Y
>>> Y
Matrix([
[1, 2],
[3, 5]])
"""
return MutableSparseMatrix(self)
def col_list(self):
"""Returns a column-sorted list of non-zero elements of the matrix.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> a=SparseMatrix(((1, 2), (3, 4)))
>>> a
Matrix([
[1, 2],
[3, 4]])
>>> a.CL
[(0, 0, 1), (1, 0, 3), (0, 1, 2), (1, 1, 4)]
See Also
========
sympy.matrices.sparse.MutableSparseMatrix.col_op
sympy.matrices.sparse.SparseMatrix.row_list
"""
return [tuple(k + (self[k],)) for k in sorted(list(self._smat.keys()), key=lambda k: list(reversed(k)))]
def copy(self):
return self._new(self.rows, self.cols, self._smat)
def nnz(self):
"""Returns the number of non-zero elements in Matrix."""
return len(self._smat)
def row_list(self):
"""Returns a row-sorted list of non-zero elements of the matrix.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> a = SparseMatrix(((1, 2), (3, 4)))
>>> a
Matrix([
[1, 2],
[3, 4]])
>>> a.RL
[(0, 0, 1), (0, 1, 2), (1, 0, 3), (1, 1, 4)]
See Also
========
sympy.matrices.sparse.MutableSparseMatrix.row_op
sympy.matrices.sparse.SparseMatrix.col_list
"""
return [tuple(k + (self[k],)) for k in
sorted(list(self._smat.keys()), key=lambda k: list(k))]
def scalar_multiply(self, scalar):
"Scalar element-wise multiplication"
M = self.zeros(*self.shape)
if scalar:
for i in self._smat:
v = scalar*self._smat[i]
if v:
M._smat[i] = v
else:
M._smat.pop(i, None)
return M
def solve_least_squares(self, rhs, method='LDL'):
"""Return the least-square fit to the data.
By default the cholesky_solve routine is used (method='CH'); other
methods of matrix inversion can be used. To find out which are
available, see the docstring of the .inv() method.
Examples
========
>>> from sympy.matrices import SparseMatrix, Matrix, ones
>>> A = Matrix([1, 2, 3])
>>> B = Matrix([2, 3, 4])
>>> S = SparseMatrix(A.row_join(B))
>>> S
Matrix([
[1, 2],
[2, 3],
[3, 4]])
If each line of S represent coefficients of Ax + By
and x and y are [2, 3] then S*xy is:
>>> r = S*Matrix([2, 3]); r
Matrix([
[ 8],
[13],
[18]])
But let's add 1 to the middle value and then solve for the
least-squares value of xy:
>>> xy = S.solve_least_squares(Matrix([8, 14, 18])); xy
Matrix([
[ 5/3],
[10/3]])
The error is given by S*xy - r:
>>> S*xy - r
Matrix([
[1/3],
[1/3],
[1/3]])
>>> _.norm().n(2)
0.58
If a different xy is used, the norm will be higher:
>>> xy += ones(2, 1)/10
>>> (S*xy - r).norm().n(2)
1.5
"""
t = self.T
return (t*self).inv(method=method)*t*rhs
def solve(self, rhs, method='LDL'):
"""Return solution to self*soln = rhs using given inversion method.
For a list of possible inversion methods, see the .inv() docstring.
"""
if not self.is_square:
if self.rows < self.cols:
raise ValueError('Under-determined system.')
elif self.rows > self.cols:
raise ValueError('For over-determined system, M, having '
'more rows than columns, try M.solve_least_squares(rhs).')
else:
return self.inv(method=method).multiply(rhs)
RL = property(row_list, None, None, "Alternate faster representation")
CL = property(col_list, None, None, "Alternate faster representation")
def liupc(self):
return _liupc(self)
def row_structure_symbolic_cholesky(self):
return _row_structure_symbolic_cholesky(self)
def cholesky(self, hermitian=True):
return _cholesky_sparse(self, hermitian=hermitian)
def LDLdecomposition(self, hermitian=True):
return _LDLdecomposition_sparse(self, hermitian=hermitian)
def lower_triangular_solve(self, rhs):
return _lower_triangular_solve_sparse(self, rhs)
def upper_triangular_solve(self, rhs):
return _upper_triangular_solve_sparse(self, rhs)
liupc.__doc__ = _liupc.__doc__
row_structure_symbolic_cholesky.__doc__ = _row_structure_symbolic_cholesky.__doc__
cholesky.__doc__ = _cholesky_sparse.__doc__
LDLdecomposition.__doc__ = _LDLdecomposition_sparse.__doc__
lower_triangular_solve.__doc__ = lower_triangular_solve.__doc__
upper_triangular_solve.__doc__ = upper_triangular_solve.__doc__
class MutableSparseMatrix(SparseMatrix, MatrixBase):
def __new__(cls, *args, **kwargs):
return cls._new(*args, **kwargs)
@classmethod
def _new(cls, *args, **kwargs):
obj = super().__new__(cls)
rows, cols, smat = cls._handle_creation_inputs(*args, **kwargs)
obj.rows = rows
obj.cols = cols
obj._smat = smat
return obj
def __setitem__(self, key, value):
"""Assign value to position designated by key.
Examples
========
>>> from sympy.matrices import SparseMatrix, ones
>>> M = SparseMatrix(2, 2, {})
>>> M[1] = 1; M
Matrix([
[0, 1],
[0, 0]])
>>> M[1, 1] = 2; M
Matrix([
[0, 1],
[0, 2]])
>>> M = SparseMatrix(2, 2, {})
>>> M[:, 1] = [1, 1]; M
Matrix([
[0, 1],
[0, 1]])
>>> M = SparseMatrix(2, 2, {})
>>> M[1, :] = [[1, 1]]; M
Matrix([
[0, 0],
[1, 1]])
To replace row r you assign to position r*m where m
is the number of columns:
>>> M = SparseMatrix(4, 4, {})
>>> m = M.cols
>>> M[3*m] = ones(1, m)*2; M
Matrix([
[0, 0, 0, 0],
[0, 0, 0, 0],
[0, 0, 0, 0],
[2, 2, 2, 2]])
And to replace column c you can assign to position c:
>>> M[2] = ones(m, 1)*4; M
Matrix([
[0, 0, 4, 0],
[0, 0, 4, 0],
[0, 0, 4, 0],
[2, 2, 4, 2]])
"""
rv = self._setitem(key, value)
if rv is not None:
i, j, value = rv
if value:
self._smat[i, j] = value
elif (i, j) in self._smat:
del self._smat[i, j]
def as_mutable(self):
return self.copy()
__hash__ = None # type: ignore
def _eval_col_del(self, k):
newD = {}
for i, j in self._smat:
if j == k:
pass
elif j > k:
newD[i, j - 1] = self._smat[i, j]
else:
newD[i, j] = self._smat[i, j]
self._smat = newD
self.cols -= 1
def _eval_row_del(self, k):
newD = {}
for i, j in self._smat:
if i == k:
pass
elif i > k:
newD[i - 1, j] = self._smat[i, j]
else:
newD[i, j] = self._smat[i, j]
self._smat = newD
self.rows -= 1
def col_join(self, other):
"""Returns B augmented beneath A (row-wise joining)::
[A]
[B]
Examples
========
>>> from sympy import SparseMatrix, Matrix, ones
>>> A = SparseMatrix(ones(3))
>>> A
Matrix([
[1, 1, 1],
[1, 1, 1],
[1, 1, 1]])
>>> B = SparseMatrix.eye(3)
>>> B
Matrix([
[1, 0, 0],
[0, 1, 0],
[0, 0, 1]])
>>> C = A.col_join(B); C
Matrix([
[1, 1, 1],
[1, 1, 1],
[1, 1, 1],
[1, 0, 0],
[0, 1, 0],
[0, 0, 1]])
>>> C == A.col_join(Matrix(B))
True
Joining along columns is the same as appending rows at the end
of the matrix:
>>> C == A.row_insert(A.rows, Matrix(B))
True
"""
# A null matrix can always be stacked (see #10770)
if self.rows == 0 and self.cols != other.cols:
return self._new(0, other.cols, []).col_join(other)
A, B = self, other
if not A.cols == B.cols:
raise ShapeError()
A = A.copy()
if not isinstance(B, SparseMatrix):
k = 0
b = B._mat
for i in range(B.rows):
for j in range(B.cols):
v = b[k]
if v:
A._smat[i + A.rows, j] = v
k += 1
else:
for (i, j), v in B._smat.items():
A._smat[i + A.rows, j] = v
A.rows += B.rows
return A
def col_op(self, j, f):
"""In-place operation on col j using two-arg functor whose args are
interpreted as (self[i, j], i) for i in range(self.rows).
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> M = SparseMatrix.eye(3)*2
>>> M[1, 0] = -1
>>> M.col_op(1, lambda v, i: v + 2*M[i, 0]); M
Matrix([
[ 2, 4, 0],
[-1, 0, 0],
[ 0, 0, 2]])
"""
for i in range(self.rows):
v = self._smat.get((i, j), S.Zero)
fv = f(v, i)
if fv:
self._smat[i, j] = fv
elif v:
self._smat.pop((i, j))
def col_swap(self, i, j):
"""Swap, in place, columns i and j.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> S = SparseMatrix.eye(3); S[2, 1] = 2
>>> S.col_swap(1, 0); S
Matrix([
[0, 1, 0],
[1, 0, 0],
[2, 0, 1]])
"""
if i > j:
i, j = j, i
rows = self.col_list()
temp = []
for ii, jj, v in rows:
if jj == i:
self._smat.pop((ii, jj))
temp.append((ii, v))
elif jj == j:
self._smat.pop((ii, jj))
self._smat[ii, i] = v
elif jj > j:
break
for k, v in temp:
self._smat[k, j] = v
def copyin_list(self, key, value):
if not is_sequence(value):
raise TypeError("`value` must be of type list or tuple.")
self.copyin_matrix(key, Matrix(value))
def copyin_matrix(self, key, value):
# include this here because it's not part of BaseMatrix
rlo, rhi, clo, chi = self.key2bounds(key)
shape = value.shape
dr, dc = rhi - rlo, chi - clo
if shape != (dr, dc):
raise ShapeError(
"The Matrix `value` doesn't have the same dimensions "
"as the in sub-Matrix given by `key`.")
if not isinstance(value, SparseMatrix):
for i in range(value.rows):
for j in range(value.cols):
self[i + rlo, j + clo] = value[i, j]
else:
if (rhi - rlo)*(chi - clo) < len(self):
for i in range(rlo, rhi):
for j in range(clo, chi):
self._smat.pop((i, j), None)
else:
for i, j, v in self.row_list():
if rlo <= i < rhi and clo <= j < chi:
self._smat.pop((i, j), None)
for k, v in value._smat.items():
i, j = k
self[i + rlo, j + clo] = value[i, j]
def fill(self, value):
"""Fill self with the given value.
Notes
=====
Unless many values are going to be deleted (i.e. set to zero)
this will create a matrix that is slower than a dense matrix in
operations.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> M = SparseMatrix.zeros(3); M
Matrix([
[0, 0, 0],
[0, 0, 0],
[0, 0, 0]])
>>> M.fill(1); M
Matrix([
[1, 1, 1],
[1, 1, 1],
[1, 1, 1]])
"""
if not value:
self._smat = {}
else:
v = self._sympify(value)
self._smat = {(i, j): v
for i in range(self.rows) for j in range(self.cols)}
def row_join(self, other):
"""Returns B appended after A (column-wise augmenting)::
[A B]
Examples
========
>>> from sympy import SparseMatrix, Matrix
>>> A = SparseMatrix(((1, 0, 1), (0, 1, 0), (1, 1, 0)))
>>> A
Matrix([
[1, 0, 1],
[0, 1, 0],
[1, 1, 0]])
>>> B = SparseMatrix(((1, 0, 0), (0, 1, 0), (0, 0, 1)))
>>> B
Matrix([
[1, 0, 0],
[0, 1, 0],
[0, 0, 1]])
>>> C = A.row_join(B); C
Matrix([
[1, 0, 1, 1, 0, 0],
[0, 1, 0, 0, 1, 0],
[1, 1, 0, 0, 0, 1]])
>>> C == A.row_join(Matrix(B))
True
Joining at row ends is the same as appending columns at the end
of the matrix:
>>> C == A.col_insert(A.cols, B)
True
"""
# A null matrix can always be stacked (see #10770)
if self.cols == 0 and self.rows != other.rows:
return self._new(other.rows, 0, []).row_join(other)
A, B = self, other
if not A.rows == B.rows:
raise ShapeError()
A = A.copy()
if not isinstance(B, SparseMatrix):
k = 0
b = B._mat
for i in range(B.rows):
for j in range(B.cols):
v = b[k]
if v:
A._smat[i, j + A.cols] = v
k += 1
else:
for (i, j), v in B._smat.items():
A._smat[i, j + A.cols] = v
A.cols += B.cols
return A
def row_op(self, i, f):
"""In-place operation on row ``i`` using two-arg functor whose args are
interpreted as ``(self[i, j], j)``.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> M = SparseMatrix.eye(3)*2
>>> M[0, 1] = -1
>>> M.row_op(1, lambda v, j: v + 2*M[0, j]); M
Matrix([
[2, -1, 0],
[4, 0, 0],
[0, 0, 2]])
See Also
========
row
zip_row_op
col_op
"""
for j in range(self.cols):
v = self._smat.get((i, j), S.Zero)
fv = f(v, j)
if fv:
self._smat[i, j] = fv
elif v:
self._smat.pop((i, j))
def row_swap(self, i, j):
"""Swap, in place, columns i and j.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> S = SparseMatrix.eye(3); S[2, 1] = 2
>>> S.row_swap(1, 0); S
Matrix([
[0, 1, 0],
[1, 0, 0],
[0, 2, 1]])
"""
if i > j:
i, j = j, i
rows = self.row_list()
temp = []
for ii, jj, v in rows:
if ii == i:
self._smat.pop((ii, jj))
temp.append((jj, v))
elif ii == j:
self._smat.pop((ii, jj))
self._smat[i, jj] = v
elif ii > j:
break
for k, v in temp:
self._smat[j, k] = v
def zip_row_op(self, i, k, f):
"""In-place operation on row ``i`` using two-arg functor whose args are
interpreted as ``(self[i, j], self[k, j])``.
Examples
========
>>> from sympy.matrices import SparseMatrix
>>> M = SparseMatrix.eye(3)*2
>>> M[0, 1] = -1
>>> M.zip_row_op(1, 0, lambda v, u: v + 2*u); M
Matrix([
[2, -1, 0],
[4, 0, 0],
[0, 0, 2]])
See Also
========
row
row_op
col_op
"""
self.row_op(i, lambda v, j: f(v, self[k, j]))
is_zero = False
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