3286 lines
94 KiB
Python
3286 lines
94 KiB
Python
"""
|
|
Basic methods common to all matrices to be used
|
|
when creating more advanced matrices (e.g., matrices over rings,
|
|
etc.).
|
|
"""
|
|
|
|
from collections import defaultdict
|
|
from collections.abc import Iterable
|
|
from inspect import isfunction
|
|
from functools import reduce
|
|
|
|
from sympy.core.logic import FuzzyBool
|
|
from sympy.assumptions.refine import refine
|
|
from sympy.core import SympifyError, Add
|
|
from sympy.core.basic import Atom
|
|
from sympy.core.compatibility import as_int, is_sequence
|
|
from sympy.core.decorators import call_highest_priority
|
|
from sympy.core.kind import Kind, NumberKind
|
|
from sympy.core.logic import fuzzy_and
|
|
from sympy.core.singleton import S
|
|
from sympy.core.symbol import Symbol
|
|
from sympy.core.sympify import sympify
|
|
from sympy.functions import Abs
|
|
from sympy.polys.polytools import Poly
|
|
from sympy.simplify import simplify as _simplify
|
|
from sympy.simplify.simplify import dotprodsimp as _dotprodsimp
|
|
from sympy.utilities.exceptions import SymPyDeprecationWarning
|
|
from sympy.utilities.iterables import flatten
|
|
from sympy.utilities.misc import filldedent
|
|
from sympy.tensor.array import NDimArray
|
|
|
|
from .utilities import _get_intermediate_simp_bool
|
|
|
|
|
|
class MatrixError(Exception):
|
|
pass
|
|
|
|
|
|
class ShapeError(ValueError, MatrixError):
|
|
"""Wrong matrix shape"""
|
|
pass
|
|
|
|
|
|
class NonSquareMatrixError(ShapeError):
|
|
pass
|
|
|
|
|
|
class NonInvertibleMatrixError(ValueError, MatrixError):
|
|
"""The matrix in not invertible (division by multidimensional zero error)."""
|
|
pass
|
|
|
|
|
|
class NonPositiveDefiniteMatrixError(ValueError, MatrixError):
|
|
"""The matrix is not a positive-definite matrix."""
|
|
pass
|
|
|
|
|
|
class MatrixRequired:
|
|
"""All subclasses of matrix objects must implement the
|
|
required matrix properties listed here."""
|
|
rows = None # type: int
|
|
cols = None # type: int
|
|
_simplify = None
|
|
|
|
@classmethod
|
|
def _new(cls, *args, **kwargs):
|
|
"""`_new` must, at minimum, be callable as
|
|
`_new(rows, cols, mat) where mat is a flat list of the
|
|
elements of the matrix."""
|
|
raise NotImplementedError("Subclasses must implement this.")
|
|
|
|
def __eq__(self, other):
|
|
raise NotImplementedError("Subclasses must implement this.")
|
|
|
|
def __getitem__(self, key):
|
|
"""Implementations of __getitem__ should accept ints, in which
|
|
case the matrix is indexed as a flat list, tuples (i,j) in which
|
|
case the (i,j) entry is returned, slices, or mixed tuples (a,b)
|
|
where a and b are any combintion of slices and integers."""
|
|
raise NotImplementedError("Subclasses must implement this.")
|
|
|
|
def __len__(self):
|
|
"""The total number of entries in the matrix."""
|
|
raise NotImplementedError("Subclasses must implement this.")
|
|
|
|
@property
|
|
def shape(self):
|
|
raise NotImplementedError("Subclasses must implement this.")
|
|
|
|
|
|
class MatrixShaping(MatrixRequired):
|
|
"""Provides basic matrix shaping and extracting of submatrices"""
|
|
|
|
def _eval_col_del(self, col):
|
|
def entry(i, j):
|
|
return self[i, j] if j < col else self[i, j + 1]
|
|
return self._new(self.rows, self.cols - 1, entry)
|
|
|
|
def _eval_col_insert(self, pos, other):
|
|
|
|
def entry(i, j):
|
|
if j < pos:
|
|
return self[i, j]
|
|
elif pos <= j < pos + other.cols:
|
|
return other[i, j - pos]
|
|
return self[i, j - other.cols]
|
|
|
|
return self._new(self.rows, self.cols + other.cols,
|
|
lambda i, j: entry(i, j))
|
|
|
|
def _eval_col_join(self, other):
|
|
rows = self.rows
|
|
|
|
def entry(i, j):
|
|
if i < rows:
|
|
return self[i, j]
|
|
return other[i - rows, j]
|
|
|
|
return classof(self, other)._new(self.rows + other.rows, self.cols,
|
|
lambda i, j: entry(i, j))
|
|
|
|
def _eval_extract(self, rowsList, colsList):
|
|
mat = list(self)
|
|
cols = self.cols
|
|
indices = (i * cols + j for i in rowsList for j in colsList)
|
|
return self._new(len(rowsList), len(colsList),
|
|
list(mat[i] for i in indices))
|
|
|
|
def _eval_get_diag_blocks(self):
|
|
sub_blocks = []
|
|
|
|
def recurse_sub_blocks(M):
|
|
i = 1
|
|
while i <= M.shape[0]:
|
|
if i == 1:
|
|
to_the_right = M[0, i:]
|
|
to_the_bottom = M[i:, 0]
|
|
else:
|
|
to_the_right = M[:i, i:]
|
|
to_the_bottom = M[i:, :i]
|
|
if any(to_the_right) or any(to_the_bottom):
|
|
i += 1
|
|
continue
|
|
else:
|
|
sub_blocks.append(M[:i, :i])
|
|
if M.shape == M[:i, :i].shape:
|
|
return
|
|
else:
|
|
recurse_sub_blocks(M[i:, i:])
|
|
return
|
|
|
|
recurse_sub_blocks(self)
|
|
return sub_blocks
|
|
|
|
def _eval_row_del(self, row):
|
|
def entry(i, j):
|
|
return self[i, j] if i < row else self[i + 1, j]
|
|
return self._new(self.rows - 1, self.cols, entry)
|
|
|
|
def _eval_row_insert(self, pos, other):
|
|
entries = list(self)
|
|
insert_pos = pos * self.cols
|
|
entries[insert_pos:insert_pos] = list(other)
|
|
return self._new(self.rows + other.rows, self.cols, entries)
|
|
|
|
def _eval_row_join(self, other):
|
|
cols = self.cols
|
|
|
|
def entry(i, j):
|
|
if j < cols:
|
|
return self[i, j]
|
|
return other[i, j - cols]
|
|
|
|
return classof(self, other)._new(self.rows, self.cols + other.cols,
|
|
lambda i, j: entry(i, j))
|
|
|
|
def _eval_tolist(self):
|
|
return [list(self[i,:]) for i in range(self.rows)]
|
|
|
|
def _eval_todok(self):
|
|
dok = {}
|
|
rows, cols = self.shape
|
|
for i in range(rows):
|
|
for j in range(cols):
|
|
val = self[i, j]
|
|
if val != self.zero:
|
|
dok[i, j] = val
|
|
return dok
|
|
|
|
def _eval_vec(self):
|
|
rows = self.rows
|
|
|
|
def entry(n, _):
|
|
# we want to read off the columns first
|
|
j = n // rows
|
|
i = n - j * rows
|
|
return self[i, j]
|
|
|
|
return self._new(len(self), 1, entry)
|
|
|
|
def _eval_vech(self, diagonal):
|
|
c = self.cols
|
|
v = []
|
|
if diagonal:
|
|
for j in range(c):
|
|
for i in range(j, c):
|
|
v.append(self[i, j])
|
|
else:
|
|
for j in range(c):
|
|
for i in range(j + 1, c):
|
|
v.append(self[i, j])
|
|
return self._new(len(v), 1, v)
|
|
|
|
def col_del(self, col):
|
|
"""Delete the specified column."""
|
|
if col < 0:
|
|
col += self.cols
|
|
if not 0 <= col < self.cols:
|
|
raise IndexError("Column {} is out of range.".format(col))
|
|
return self._eval_col_del(col)
|
|
|
|
def col_insert(self, pos, other):
|
|
"""Insert one or more columns at the given column position.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import zeros, ones
|
|
>>> M = zeros(3)
|
|
>>> V = ones(3, 1)
|
|
>>> M.col_insert(1, V)
|
|
Matrix([
|
|
[0, 1, 0, 0],
|
|
[0, 1, 0, 0],
|
|
[0, 1, 0, 0]])
|
|
|
|
See Also
|
|
========
|
|
|
|
col
|
|
row_insert
|
|
"""
|
|
# Allows you to build a matrix even if it is null matrix
|
|
if not self:
|
|
return type(self)(other)
|
|
|
|
pos = as_int(pos)
|
|
|
|
if pos < 0:
|
|
pos = self.cols + pos
|
|
if pos < 0:
|
|
pos = 0
|
|
elif pos > self.cols:
|
|
pos = self.cols
|
|
|
|
if self.rows != other.rows:
|
|
raise ShapeError(
|
|
"`self` and `other` must have the same number of rows.")
|
|
|
|
return self._eval_col_insert(pos, other)
|
|
|
|
def col_join(self, other):
|
|
"""Concatenates two matrices along self's last and other's first row.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import zeros, ones
|
|
>>> M = zeros(3)
|
|
>>> V = ones(1, 3)
|
|
>>> M.col_join(V)
|
|
Matrix([
|
|
[0, 0, 0],
|
|
[0, 0, 0],
|
|
[0, 0, 0],
|
|
[1, 1, 1]])
|
|
|
|
See Also
|
|
========
|
|
|
|
col
|
|
row_join
|
|
"""
|
|
# 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)
|
|
|
|
if self.cols != other.cols:
|
|
raise ShapeError(
|
|
"`self` and `other` must have the same number of columns.")
|
|
return self._eval_col_join(other)
|
|
|
|
def col(self, j):
|
|
"""Elementary column selector.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import eye
|
|
>>> eye(2).col(0)
|
|
Matrix([
|
|
[1],
|
|
[0]])
|
|
|
|
See Also
|
|
========
|
|
|
|
row
|
|
col_del
|
|
col_join
|
|
col_insert
|
|
"""
|
|
return self[:, j]
|
|
|
|
def extract(self, rowsList, colsList):
|
|
"""Return a submatrix by specifying a list of rows and columns.
|
|
Negative indices can be given. All indices must be in the range
|
|
-n <= i < n where n is the number of rows or columns.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(4, 3, range(12))
|
|
>>> m
|
|
Matrix([
|
|
[0, 1, 2],
|
|
[3, 4, 5],
|
|
[6, 7, 8],
|
|
[9, 10, 11]])
|
|
>>> m.extract([0, 1, 3], [0, 1])
|
|
Matrix([
|
|
[0, 1],
|
|
[3, 4],
|
|
[9, 10]])
|
|
|
|
Rows or columns can be repeated:
|
|
|
|
>>> m.extract([0, 0, 1], [-1])
|
|
Matrix([
|
|
[2],
|
|
[2],
|
|
[5]])
|
|
|
|
Every other row can be taken by using range to provide the indices:
|
|
|
|
>>> m.extract(range(0, m.rows, 2), [-1])
|
|
Matrix([
|
|
[2],
|
|
[8]])
|
|
|
|
RowsList or colsList can also be a list of booleans, in which case
|
|
the rows or columns corresponding to the True values will be selected:
|
|
|
|
>>> m.extract([0, 1, 2, 3], [True, False, True])
|
|
Matrix([
|
|
[0, 2],
|
|
[3, 5],
|
|
[6, 8],
|
|
[9, 11]])
|
|
"""
|
|
|
|
if not is_sequence(rowsList) or not is_sequence(colsList):
|
|
raise TypeError("rowsList and colsList must be iterable")
|
|
# ensure rowsList and colsList are lists of integers
|
|
if rowsList and all(isinstance(i, bool) for i in rowsList):
|
|
rowsList = [index for index, item in enumerate(rowsList) if item]
|
|
if colsList and all(isinstance(i, bool) for i in colsList):
|
|
colsList = [index for index, item in enumerate(colsList) if item]
|
|
|
|
# ensure everything is in range
|
|
rowsList = [a2idx(k, self.rows) for k in rowsList]
|
|
colsList = [a2idx(k, self.cols) for k in colsList]
|
|
|
|
return self._eval_extract(rowsList, colsList)
|
|
|
|
def get_diag_blocks(self):
|
|
"""Obtains the square sub-matrices on the main diagonal of a square matrix.
|
|
|
|
Useful for inverting symbolic matrices or solving systems of
|
|
linear equations which may be decoupled by having a block diagonal
|
|
structure.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> from sympy.abc import x, y, z
|
|
>>> A = Matrix([[1, 3, 0, 0], [y, z*z, 0, 0], [0, 0, x, 0], [0, 0, 0, 0]])
|
|
>>> a1, a2, a3 = A.get_diag_blocks()
|
|
>>> a1
|
|
Matrix([
|
|
[1, 3],
|
|
[y, z**2]])
|
|
>>> a2
|
|
Matrix([[x]])
|
|
>>> a3
|
|
Matrix([[0]])
|
|
|
|
"""
|
|
return self._eval_get_diag_blocks()
|
|
|
|
@classmethod
|
|
def hstack(cls, *args):
|
|
"""Return a matrix formed by joining args horizontally (i.e.
|
|
by repeated application of row_join).
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix, eye
|
|
>>> Matrix.hstack(eye(2), 2*eye(2))
|
|
Matrix([
|
|
[1, 0, 2, 0],
|
|
[0, 1, 0, 2]])
|
|
"""
|
|
if len(args) == 0:
|
|
return cls._new()
|
|
|
|
kls = type(args[0])
|
|
return reduce(kls.row_join, args)
|
|
|
|
def reshape(self, rows, cols):
|
|
"""Reshape the matrix. Total number of elements must remain the same.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(2, 3, lambda i, j: 1)
|
|
>>> m
|
|
Matrix([
|
|
[1, 1, 1],
|
|
[1, 1, 1]])
|
|
>>> m.reshape(1, 6)
|
|
Matrix([[1, 1, 1, 1, 1, 1]])
|
|
>>> m.reshape(3, 2)
|
|
Matrix([
|
|
[1, 1],
|
|
[1, 1],
|
|
[1, 1]])
|
|
|
|
"""
|
|
if self.rows * self.cols != rows * cols:
|
|
raise ValueError("Invalid reshape parameters %d %d" % (rows, cols))
|
|
return self._new(rows, cols, lambda i, j: self[i * cols + j])
|
|
|
|
def row_del(self, row):
|
|
"""Delete the specified row."""
|
|
if row < 0:
|
|
row += self.rows
|
|
if not 0 <= row < self.rows:
|
|
raise IndexError("Row {} is out of range.".format(row))
|
|
|
|
return self._eval_row_del(row)
|
|
|
|
def row_insert(self, pos, other):
|
|
"""Insert one or more rows at the given row position.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import zeros, ones
|
|
>>> M = zeros(3)
|
|
>>> V = ones(1, 3)
|
|
>>> M.row_insert(1, V)
|
|
Matrix([
|
|
[0, 0, 0],
|
|
[1, 1, 1],
|
|
[0, 0, 0],
|
|
[0, 0, 0]])
|
|
|
|
See Also
|
|
========
|
|
|
|
row
|
|
col_insert
|
|
"""
|
|
# Allows you to build a matrix even if it is null matrix
|
|
if not self:
|
|
return self._new(other)
|
|
|
|
pos = as_int(pos)
|
|
|
|
if pos < 0:
|
|
pos = self.rows + pos
|
|
if pos < 0:
|
|
pos = 0
|
|
elif pos > self.rows:
|
|
pos = self.rows
|
|
|
|
if self.cols != other.cols:
|
|
raise ShapeError(
|
|
"`self` and `other` must have the same number of columns.")
|
|
|
|
return self._eval_row_insert(pos, other)
|
|
|
|
def row_join(self, other):
|
|
"""Concatenates two matrices along self's last and rhs's first column
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import zeros, ones
|
|
>>> M = zeros(3)
|
|
>>> V = ones(3, 1)
|
|
>>> M.row_join(V)
|
|
Matrix([
|
|
[0, 0, 0, 1],
|
|
[0, 0, 0, 1],
|
|
[0, 0, 0, 1]])
|
|
|
|
See Also
|
|
========
|
|
|
|
row
|
|
col_join
|
|
"""
|
|
# 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)
|
|
|
|
if self.rows != other.rows:
|
|
raise ShapeError(
|
|
"`self` and `rhs` must have the same number of rows.")
|
|
return self._eval_row_join(other)
|
|
|
|
def diagonal(self, k=0):
|
|
"""Returns the kth diagonal of self. The main diagonal
|
|
corresponds to `k=0`; diagonals above and below correspond to
|
|
`k > 0` and `k < 0`, respectively. The values of `self[i, j]`
|
|
for which `j - i = k`, are returned in order of increasing
|
|
`i + j`, starting with `i + j = |k|`.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(3, 3, lambda i, j: j - i); m
|
|
Matrix([
|
|
[ 0, 1, 2],
|
|
[-1, 0, 1],
|
|
[-2, -1, 0]])
|
|
>>> _.diagonal()
|
|
Matrix([[0, 0, 0]])
|
|
>>> m.diagonal(1)
|
|
Matrix([[1, 1]])
|
|
>>> m.diagonal(-2)
|
|
Matrix([[-2]])
|
|
|
|
Even though the diagonal is returned as a Matrix, the element
|
|
retrieval can be done with a single index:
|
|
|
|
>>> Matrix.diag(1, 2, 3).diagonal()[1] # instead of [0, 1]
|
|
2
|
|
|
|
See Also
|
|
========
|
|
diag - to create a diagonal matrix
|
|
"""
|
|
rv = []
|
|
k = as_int(k)
|
|
r = 0 if k > 0 else -k
|
|
c = 0 if r else k
|
|
while True:
|
|
if r == self.rows or c == self.cols:
|
|
break
|
|
rv.append(self[r, c])
|
|
r += 1
|
|
c += 1
|
|
if not rv:
|
|
raise ValueError(filldedent('''
|
|
The %s diagonal is out of range [%s, %s]''' % (
|
|
k, 1 - self.rows, self.cols - 1)))
|
|
return self._new(1, len(rv), rv)
|
|
|
|
def row(self, i):
|
|
"""Elementary row selector.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import eye
|
|
>>> eye(2).row(0)
|
|
Matrix([[1, 0]])
|
|
|
|
See Also
|
|
========
|
|
|
|
col
|
|
row_del
|
|
row_join
|
|
row_insert
|
|
"""
|
|
return self[i, :]
|
|
|
|
@property
|
|
def shape(self):
|
|
"""The shape (dimensions) of the matrix as the 2-tuple (rows, cols).
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import zeros
|
|
>>> M = zeros(2, 3)
|
|
>>> M.shape
|
|
(2, 3)
|
|
>>> M.rows
|
|
2
|
|
>>> M.cols
|
|
3
|
|
"""
|
|
return (self.rows, self.cols)
|
|
|
|
def todok(self):
|
|
"""Return the matrix as dictionary of keys.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> M = Matrix.eye(3)
|
|
>>> M.todok()
|
|
{(0, 0): 1, (1, 1): 1, (2, 2): 1}
|
|
"""
|
|
return self._eval_todok()
|
|
|
|
def tolist(self):
|
|
"""Return the Matrix as a nested Python list.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, ones
|
|
>>> m = Matrix(3, 3, range(9))
|
|
>>> m
|
|
Matrix([
|
|
[0, 1, 2],
|
|
[3, 4, 5],
|
|
[6, 7, 8]])
|
|
>>> m.tolist()
|
|
[[0, 1, 2], [3, 4, 5], [6, 7, 8]]
|
|
>>> ones(3, 0).tolist()
|
|
[[], [], []]
|
|
|
|
When there are no rows then it will not be possible to tell how
|
|
many columns were in the original matrix:
|
|
|
|
>>> ones(0, 3).tolist()
|
|
[]
|
|
|
|
"""
|
|
if not self.rows:
|
|
return []
|
|
if not self.cols:
|
|
return [[] for i in range(self.rows)]
|
|
return self._eval_tolist()
|
|
|
|
def todod(M):
|
|
"""Returns matrix as dict of dicts containing non-zero elements of the Matrix
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> A = Matrix([[0, 1],[0, 3]])
|
|
>>> A
|
|
Matrix([
|
|
[0, 1],
|
|
[0, 3]])
|
|
>>> A.todod()
|
|
{0: {1: 1}, 1: {1: 3}}
|
|
|
|
|
|
"""
|
|
rowsdict = {}
|
|
Mlol = M.tolist()
|
|
for i, Mi in enumerate(Mlol):
|
|
row = {j: Mij for j, Mij in enumerate(Mi) if Mij}
|
|
if row:
|
|
rowsdict[i] = row
|
|
return rowsdict
|
|
|
|
def vec(self):
|
|
"""Return the Matrix converted into a one column matrix by stacking columns
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m=Matrix([[1, 3], [2, 4]])
|
|
>>> m
|
|
Matrix([
|
|
[1, 3],
|
|
[2, 4]])
|
|
>>> m.vec()
|
|
Matrix([
|
|
[1],
|
|
[2],
|
|
[3],
|
|
[4]])
|
|
|
|
See Also
|
|
========
|
|
|
|
vech
|
|
"""
|
|
return self._eval_vec()
|
|
|
|
def vech(self, diagonal=True, check_symmetry=True):
|
|
"""Reshapes the matrix into a column vector by stacking the
|
|
elements in the lower triangle.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
diagonal : bool, optional
|
|
If ``True``, it includes the diagonal elements.
|
|
|
|
check_symmetry : bool, optional
|
|
If ``True``, it checks whether the matrix is symmetric.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m=Matrix([[1, 2], [2, 3]])
|
|
>>> m
|
|
Matrix([
|
|
[1, 2],
|
|
[2, 3]])
|
|
>>> m.vech()
|
|
Matrix([
|
|
[1],
|
|
[2],
|
|
[3]])
|
|
>>> m.vech(diagonal=False)
|
|
Matrix([[2]])
|
|
|
|
Notes
|
|
=====
|
|
|
|
This should work for symmetric matrices and ``vech`` can
|
|
represent symmetric matrices in vector form with less size than
|
|
``vec``.
|
|
|
|
See Also
|
|
========
|
|
|
|
vec
|
|
"""
|
|
if not self.is_square:
|
|
raise NonSquareMatrixError
|
|
|
|
if check_symmetry and not self.is_symmetric():
|
|
raise ValueError("The matrix is not symmetric.")
|
|
|
|
return self._eval_vech(diagonal)
|
|
|
|
@classmethod
|
|
def vstack(cls, *args):
|
|
"""Return a matrix formed by joining args vertically (i.e.
|
|
by repeated application of col_join).
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix, eye
|
|
>>> Matrix.vstack(eye(2), 2*eye(2))
|
|
Matrix([
|
|
[1, 0],
|
|
[0, 1],
|
|
[2, 0],
|
|
[0, 2]])
|
|
"""
|
|
if len(args) == 0:
|
|
return cls._new()
|
|
|
|
kls = type(args[0])
|
|
return reduce(kls.col_join, args)
|
|
|
|
|
|
class MatrixSpecial(MatrixRequired):
|
|
"""Construction of special matrices"""
|
|
|
|
@classmethod
|
|
def _eval_diag(cls, rows, cols, diag_dict):
|
|
"""diag_dict is a defaultdict containing
|
|
all the entries of the diagonal matrix."""
|
|
def entry(i, j):
|
|
return diag_dict[(i, j)]
|
|
return cls._new(rows, cols, entry)
|
|
|
|
@classmethod
|
|
def _eval_eye(cls, rows, cols):
|
|
vals = [cls.zero]*(rows*cols)
|
|
vals[::cols+1] = [cls.one]*min(rows, cols)
|
|
return cls._new(rows, cols, vals, copy=False)
|
|
|
|
@classmethod
|
|
def _eval_jordan_block(cls, rows, cols, eigenvalue, band='upper'):
|
|
if band == 'lower':
|
|
def entry(i, j):
|
|
if i == j:
|
|
return eigenvalue
|
|
elif j + 1 == i:
|
|
return cls.one
|
|
return cls.zero
|
|
else:
|
|
def entry(i, j):
|
|
if i == j:
|
|
return eigenvalue
|
|
elif i + 1 == j:
|
|
return cls.one
|
|
return cls.zero
|
|
return cls._new(rows, cols, entry)
|
|
|
|
@classmethod
|
|
def _eval_ones(cls, rows, cols):
|
|
def entry(i, j):
|
|
return cls.one
|
|
return cls._new(rows, cols, entry)
|
|
|
|
@classmethod
|
|
def _eval_zeros(cls, rows, cols):
|
|
return cls._new(rows, cols, [cls.zero]*(rows*cols), copy=False)
|
|
|
|
@classmethod
|
|
def _eval_wilkinson(cls, n):
|
|
def entry(i, j):
|
|
return cls.one if i + 1 == j else cls.zero
|
|
|
|
D = cls._new(2*n + 1, 2*n + 1, entry)
|
|
|
|
wminus = cls.diag([i for i in range(-n, n + 1)], unpack=True) + D + D.T
|
|
wplus = abs(cls.diag([i for i in range(-n, n + 1)], unpack=True)) + D + D.T
|
|
|
|
return wminus, wplus
|
|
|
|
@classmethod
|
|
def diag(kls, *args, strict=False, unpack=True, rows=None, cols=None, **kwargs):
|
|
"""Returns a matrix with the specified diagonal.
|
|
If matrices are passed, a block-diagonal matrix
|
|
is created (i.e. the "direct sum" of the matrices).
|
|
|
|
kwargs
|
|
======
|
|
|
|
rows : rows of the resulting matrix; computed if
|
|
not given.
|
|
|
|
cols : columns of the resulting matrix; computed if
|
|
not given.
|
|
|
|
cls : class for the resulting matrix
|
|
|
|
unpack : bool which, when True (default), unpacks a single
|
|
sequence rather than interpreting it as a Matrix.
|
|
|
|
strict : bool which, when False (default), allows Matrices to
|
|
have variable-length rows.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> Matrix.diag(1, 2, 3)
|
|
Matrix([
|
|
[1, 0, 0],
|
|
[0, 2, 0],
|
|
[0, 0, 3]])
|
|
|
|
The current default is to unpack a single sequence. If this is
|
|
not desired, set `unpack=False` and it will be interpreted as
|
|
a matrix.
|
|
|
|
>>> Matrix.diag([1, 2, 3]) == Matrix.diag(1, 2, 3)
|
|
True
|
|
|
|
When more than one element is passed, each is interpreted as
|
|
something to put on the diagonal. Lists are converted to
|
|
matrices. Filling of the diagonal always continues from
|
|
the bottom right hand corner of the previous item: this
|
|
will create a block-diagonal matrix whether the matrices
|
|
are square or not.
|
|
|
|
>>> col = [1, 2, 3]
|
|
>>> row = [[4, 5]]
|
|
>>> Matrix.diag(col, row)
|
|
Matrix([
|
|
[1, 0, 0],
|
|
[2, 0, 0],
|
|
[3, 0, 0],
|
|
[0, 4, 5]])
|
|
|
|
When `unpack` is False, elements within a list need not all be
|
|
of the same length. Setting `strict` to True would raise a
|
|
ValueError for the following:
|
|
|
|
>>> Matrix.diag([[1, 2, 3], [4, 5], [6]], unpack=False)
|
|
Matrix([
|
|
[1, 2, 3],
|
|
[4, 5, 0],
|
|
[6, 0, 0]])
|
|
|
|
The type of the returned matrix can be set with the ``cls``
|
|
keyword.
|
|
|
|
>>> from sympy.matrices import ImmutableMatrix
|
|
>>> from sympy.utilities.misc import func_name
|
|
>>> func_name(Matrix.diag(1, cls=ImmutableMatrix))
|
|
'ImmutableDenseMatrix'
|
|
|
|
A zero dimension matrix can be used to position the start of
|
|
the filling at the start of an arbitrary row or column:
|
|
|
|
>>> from sympy import ones
|
|
>>> r2 = ones(0, 2)
|
|
>>> Matrix.diag(r2, 1, 2)
|
|
Matrix([
|
|
[0, 0, 1, 0],
|
|
[0, 0, 0, 2]])
|
|
|
|
See Also
|
|
========
|
|
eye
|
|
diagonal - to extract a diagonal
|
|
.dense.diag
|
|
.expressions.blockmatrix.BlockMatrix
|
|
.sparsetools.banded - to create multi-diagonal matrices
|
|
"""
|
|
from sympy.matrices.matrices import MatrixBase
|
|
from sympy.matrices.dense import Matrix
|
|
from sympy.matrices.sparse import SparseMatrix
|
|
klass = kwargs.get('cls', kls)
|
|
if unpack and len(args) == 1 and is_sequence(args[0]) and \
|
|
not isinstance(args[0], MatrixBase):
|
|
args = args[0]
|
|
|
|
# fill a default dict with the diagonal entries
|
|
diag_entries = defaultdict(int)
|
|
rmax = cmax = 0 # keep track of the biggest index seen
|
|
for m in args:
|
|
if isinstance(m, list):
|
|
if strict:
|
|
# if malformed, Matrix will raise an error
|
|
_ = Matrix(m)
|
|
r, c = _.shape
|
|
m = _.tolist()
|
|
else:
|
|
r, c, smat = SparseMatrix._handle_creation_inputs(m)
|
|
for (i, j), _ in smat.items():
|
|
diag_entries[(i + rmax, j + cmax)] = _
|
|
m = [] # to skip process below
|
|
elif hasattr(m, 'shape'): # a Matrix
|
|
# convert to list of lists
|
|
r, c = m.shape
|
|
m = m.tolist()
|
|
else: # in this case, we're a single value
|
|
diag_entries[(rmax, cmax)] = m
|
|
rmax += 1
|
|
cmax += 1
|
|
continue
|
|
# process list of lists
|
|
for i in range(len(m)):
|
|
for j, _ in enumerate(m[i]):
|
|
diag_entries[(i + rmax, j + cmax)] = _
|
|
rmax += r
|
|
cmax += c
|
|
if rows is None:
|
|
rows, cols = cols, rows
|
|
if rows is None:
|
|
rows, cols = rmax, cmax
|
|
else:
|
|
cols = rows if cols is None else cols
|
|
if rows < rmax or cols < cmax:
|
|
raise ValueError(filldedent('''
|
|
The constructed matrix is {} x {} but a size of {} x {}
|
|
was specified.'''.format(rmax, cmax, rows, cols)))
|
|
return klass._eval_diag(rows, cols, diag_entries)
|
|
|
|
@classmethod
|
|
def eye(kls, rows, cols=None, **kwargs):
|
|
"""Returns an identity matrix.
|
|
|
|
Args
|
|
====
|
|
|
|
rows : rows of the matrix
|
|
cols : cols of the matrix (if None, cols=rows)
|
|
|
|
kwargs
|
|
======
|
|
cls : class of the returned matrix
|
|
"""
|
|
if cols is None:
|
|
cols = rows
|
|
if rows < 0 or cols < 0:
|
|
raise ValueError("Cannot create a {} x {} matrix. "
|
|
"Both dimensions must be positive".format(rows, cols))
|
|
klass = kwargs.get('cls', kls)
|
|
rows, cols = as_int(rows), as_int(cols)
|
|
|
|
return klass._eval_eye(rows, cols)
|
|
|
|
@classmethod
|
|
def jordan_block(kls, size=None, eigenvalue=None, *, band='upper', **kwargs):
|
|
"""Returns a Jordan block
|
|
|
|
Parameters
|
|
==========
|
|
|
|
size : Integer, optional
|
|
Specifies the shape of the Jordan block matrix.
|
|
|
|
eigenvalue : Number or Symbol
|
|
Specifies the value for the main diagonal of the matrix.
|
|
|
|
.. note::
|
|
The keyword ``eigenval`` is also specified as an alias
|
|
of this keyword, but it is not recommended to use.
|
|
|
|
We may deprecate the alias in later release.
|
|
|
|
band : 'upper' or 'lower', optional
|
|
Specifies the position of the off-diagonal to put `1` s on.
|
|
|
|
cls : Matrix, optional
|
|
Specifies the matrix class of the output form.
|
|
|
|
If it is not specified, the class type where the method is
|
|
being executed on will be returned.
|
|
|
|
rows, cols : Integer, optional
|
|
Specifies the shape of the Jordan block matrix. See Notes
|
|
section for the details of how these key works.
|
|
|
|
.. note::
|
|
This feature will be deprecated in the future.
|
|
|
|
|
|
Returns
|
|
=======
|
|
|
|
Matrix
|
|
A Jordan block matrix.
|
|
|
|
Raises
|
|
======
|
|
|
|
ValueError
|
|
If insufficient arguments are given for matrix size
|
|
specification, or no eigenvalue is given.
|
|
|
|
Examples
|
|
========
|
|
|
|
Creating a default Jordan block:
|
|
|
|
>>> from sympy import Matrix
|
|
>>> from sympy.abc import x
|
|
>>> Matrix.jordan_block(4, x)
|
|
Matrix([
|
|
[x, 1, 0, 0],
|
|
[0, x, 1, 0],
|
|
[0, 0, x, 1],
|
|
[0, 0, 0, x]])
|
|
|
|
Creating an alternative Jordan block matrix where `1` is on
|
|
lower off-diagonal:
|
|
|
|
>>> Matrix.jordan_block(4, x, band='lower')
|
|
Matrix([
|
|
[x, 0, 0, 0],
|
|
[1, x, 0, 0],
|
|
[0, 1, x, 0],
|
|
[0, 0, 1, x]])
|
|
|
|
Creating a Jordan block with keyword arguments
|
|
|
|
>>> Matrix.jordan_block(size=4, eigenvalue=x)
|
|
Matrix([
|
|
[x, 1, 0, 0],
|
|
[0, x, 1, 0],
|
|
[0, 0, x, 1],
|
|
[0, 0, 0, x]])
|
|
|
|
Notes
|
|
=====
|
|
|
|
.. note::
|
|
This feature will be deprecated in the future.
|
|
|
|
The keyword arguments ``size``, ``rows``, ``cols`` relates to
|
|
the Jordan block size specifications.
|
|
|
|
If you want to create a square Jordan block, specify either
|
|
one of the three arguments.
|
|
|
|
If you want to create a rectangular Jordan block, specify
|
|
``rows`` and ``cols`` individually.
|
|
|
|
+--------------------------------+---------------------+
|
|
| Arguments Given | Matrix Shape |
|
|
+----------+----------+----------+----------+----------+
|
|
| size | rows | cols | rows | cols |
|
|
+==========+==========+==========+==========+==========+
|
|
| size | Any | size | size |
|
|
+----------+----------+----------+----------+----------+
|
|
| | None | ValueError |
|
|
| +----------+----------+----------+----------+
|
|
| None | rows | None | rows | rows |
|
|
| +----------+----------+----------+----------+
|
|
| | None | cols | cols | cols |
|
|
+ +----------+----------+----------+----------+
|
|
| | rows | cols | rows | cols |
|
|
+----------+----------+----------+----------+----------+
|
|
|
|
References
|
|
==========
|
|
|
|
.. [1] https://en.wikipedia.org/wiki/Jordan_matrix
|
|
"""
|
|
if 'rows' in kwargs or 'cols' in kwargs:
|
|
SymPyDeprecationWarning(
|
|
feature="Keyword arguments 'rows' or 'cols'",
|
|
issue=16102,
|
|
useinstead="a more generic banded matrix constructor",
|
|
deprecated_since_version="1.4"
|
|
).warn()
|
|
|
|
klass = kwargs.pop('cls', kls)
|
|
rows = kwargs.pop('rows', None)
|
|
cols = kwargs.pop('cols', None)
|
|
|
|
eigenval = kwargs.get('eigenval', None)
|
|
if eigenvalue is None and eigenval is None:
|
|
raise ValueError("Must supply an eigenvalue")
|
|
elif eigenvalue != eigenval and None not in (eigenval, eigenvalue):
|
|
raise ValueError(
|
|
"Inconsistent values are given: 'eigenval'={}, "
|
|
"'eigenvalue'={}".format(eigenval, eigenvalue))
|
|
else:
|
|
if eigenval is not None:
|
|
eigenvalue = eigenval
|
|
|
|
if (size, rows, cols) == (None, None, None):
|
|
raise ValueError("Must supply a matrix size")
|
|
|
|
if size is not None:
|
|
rows, cols = size, size
|
|
elif rows is not None and cols is None:
|
|
cols = rows
|
|
elif cols is not None and rows is None:
|
|
rows = cols
|
|
|
|
rows, cols = as_int(rows), as_int(cols)
|
|
|
|
return klass._eval_jordan_block(rows, cols, eigenvalue, band)
|
|
|
|
@classmethod
|
|
def ones(kls, rows, cols=None, **kwargs):
|
|
"""Returns a matrix of ones.
|
|
|
|
Args
|
|
====
|
|
|
|
rows : rows of the matrix
|
|
cols : cols of the matrix (if None, cols=rows)
|
|
|
|
kwargs
|
|
======
|
|
cls : class of the returned matrix
|
|
"""
|
|
if cols is None:
|
|
cols = rows
|
|
klass = kwargs.get('cls', kls)
|
|
rows, cols = as_int(rows), as_int(cols)
|
|
|
|
return klass._eval_ones(rows, cols)
|
|
|
|
@classmethod
|
|
def zeros(kls, rows, cols=None, **kwargs):
|
|
"""Returns a matrix of zeros.
|
|
|
|
Args
|
|
====
|
|
|
|
rows : rows of the matrix
|
|
cols : cols of the matrix (if None, cols=rows)
|
|
|
|
kwargs
|
|
======
|
|
cls : class of the returned matrix
|
|
"""
|
|
if cols is None:
|
|
cols = rows
|
|
if rows < 0 or cols < 0:
|
|
raise ValueError("Cannot create a {} x {} matrix. "
|
|
"Both dimensions must be positive".format(rows, cols))
|
|
klass = kwargs.get('cls', kls)
|
|
rows, cols = as_int(rows), as_int(cols)
|
|
|
|
return klass._eval_zeros(rows, cols)
|
|
|
|
@classmethod
|
|
def companion(kls, poly):
|
|
"""Returns a companion matrix of a polynomial.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, Poly, Symbol, symbols
|
|
>>> x = Symbol('x')
|
|
>>> c0, c1, c2, c3, c4 = symbols('c0:5')
|
|
>>> p = Poly(c0 + c1*x + c2*x**2 + c3*x**3 + c4*x**4 + x**5, x)
|
|
>>> Matrix.companion(p)
|
|
Matrix([
|
|
[0, 0, 0, 0, -c0],
|
|
[1, 0, 0, 0, -c1],
|
|
[0, 1, 0, 0, -c2],
|
|
[0, 0, 1, 0, -c3],
|
|
[0, 0, 0, 1, -c4]])
|
|
"""
|
|
poly = kls._sympify(poly)
|
|
if not isinstance(poly, Poly):
|
|
raise ValueError("{} must be a Poly instance.".format(poly))
|
|
if not poly.is_monic:
|
|
raise ValueError("{} must be a monic polynomial.".format(poly))
|
|
if not poly.is_univariate:
|
|
raise ValueError(
|
|
"{} must be a univariate polynomial.".format(poly))
|
|
|
|
size = poly.degree()
|
|
if not size >= 1:
|
|
raise ValueError(
|
|
"{} must have degree not less than 1.".format(poly))
|
|
|
|
coeffs = poly.all_coeffs()
|
|
def entry(i, j):
|
|
if j == size - 1:
|
|
return -coeffs[-1 - i]
|
|
elif i == j + 1:
|
|
return kls.one
|
|
return kls.zero
|
|
return kls._new(size, size, entry)
|
|
|
|
|
|
@classmethod
|
|
def wilkinson(kls, n, **kwargs):
|
|
"""Returns two square Wilkinson Matrix of size 2*n + 1
|
|
$W_{2n + 1}^-, W_{2n + 1}^+ =$ Wilkinson(n)
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> wminus, wplus = Matrix.wilkinson(3)
|
|
>>> wminus
|
|
Matrix([
|
|
[-3, 1, 0, 0, 0, 0, 0],
|
|
[ 1, -2, 1, 0, 0, 0, 0],
|
|
[ 0, 1, -1, 1, 0, 0, 0],
|
|
[ 0, 0, 1, 0, 1, 0, 0],
|
|
[ 0, 0, 0, 1, 1, 1, 0],
|
|
[ 0, 0, 0, 0, 1, 2, 1],
|
|
[ 0, 0, 0, 0, 0, 1, 3]])
|
|
>>> wplus
|
|
Matrix([
|
|
[3, 1, 0, 0, 0, 0, 0],
|
|
[1, 2, 1, 0, 0, 0, 0],
|
|
[0, 1, 1, 1, 0, 0, 0],
|
|
[0, 0, 1, 0, 1, 0, 0],
|
|
[0, 0, 0, 1, 1, 1, 0],
|
|
[0, 0, 0, 0, 1, 2, 1],
|
|
[0, 0, 0, 0, 0, 1, 3]])
|
|
|
|
References
|
|
==========
|
|
|
|
.. [1] https://blogs.mathworks.com/cleve/2013/04/15/wilkinsons-matrices-2/
|
|
.. [2] J. H. Wilkinson, The Algebraic Eigenvalue Problem, Claredon Press, Oxford, 1965, 662 pp.
|
|
|
|
"""
|
|
klass = kwargs.get('cls', kls)
|
|
n = as_int(n)
|
|
return klass._eval_wilkinson(n)
|
|
|
|
class MatrixProperties(MatrixRequired):
|
|
"""Provides basic properties of a matrix."""
|
|
|
|
def _eval_atoms(self, *types):
|
|
result = set()
|
|
for i in self:
|
|
result.update(i.atoms(*types))
|
|
return result
|
|
|
|
def _eval_free_symbols(self):
|
|
return set().union(*(i.free_symbols for i in self if i))
|
|
|
|
def _eval_has(self, *patterns):
|
|
return any(a.has(*patterns) for a in self)
|
|
|
|
def _eval_is_anti_symmetric(self, simpfunc):
|
|
if not all(simpfunc(self[i, j] + self[j, i]).is_zero for i in range(self.rows) for j in range(self.cols)):
|
|
return False
|
|
return True
|
|
|
|
def _eval_is_diagonal(self):
|
|
for i in range(self.rows):
|
|
for j in range(self.cols):
|
|
if i != j and self[i, j]:
|
|
return False
|
|
return True
|
|
|
|
# _eval_is_hermitian is called by some general sympy
|
|
# routines and has a different *args signature. Make
|
|
# sure the names don't clash by adding `_matrix_` in name.
|
|
def _eval_is_matrix_hermitian(self, simpfunc):
|
|
mat = self._new(self.rows, self.cols, lambda i, j: simpfunc(self[i, j] - self[j, i].conjugate()))
|
|
return mat.is_zero_matrix
|
|
|
|
def _eval_is_Identity(self) -> FuzzyBool:
|
|
def dirac(i, j):
|
|
if i == j:
|
|
return 1
|
|
return 0
|
|
|
|
return all(self[i, j] == dirac(i, j)
|
|
for i in range(self.rows)
|
|
for j in range(self.cols))
|
|
|
|
def _eval_is_lower_hessenberg(self):
|
|
return all(self[i, j].is_zero
|
|
for i in range(self.rows)
|
|
for j in range(i + 2, self.cols))
|
|
|
|
def _eval_is_lower(self):
|
|
return all(self[i, j].is_zero
|
|
for i in range(self.rows)
|
|
for j in range(i + 1, self.cols))
|
|
|
|
def _eval_is_symbolic(self):
|
|
return self.has(Symbol)
|
|
|
|
def _eval_is_symmetric(self, simpfunc):
|
|
mat = self._new(self.rows, self.cols, lambda i, j: simpfunc(self[i, j] - self[j, i]))
|
|
return mat.is_zero_matrix
|
|
|
|
def _eval_is_zero_matrix(self):
|
|
if any(i.is_zero == False for i in self):
|
|
return False
|
|
if any(i.is_zero is None for i in self):
|
|
return None
|
|
return True
|
|
|
|
def _eval_is_upper_hessenberg(self):
|
|
return all(self[i, j].is_zero
|
|
for i in range(2, self.rows)
|
|
for j in range(min(self.cols, (i - 1))))
|
|
|
|
def _eval_values(self):
|
|
return [i for i in self if not i.is_zero]
|
|
|
|
def _has_positive_diagonals(self):
|
|
diagonal_entries = (self[i, i] for i in range(self.rows))
|
|
return fuzzy_and(x.is_positive for x in diagonal_entries)
|
|
|
|
def _has_nonnegative_diagonals(self):
|
|
diagonal_entries = (self[i, i] for i in range(self.rows))
|
|
return fuzzy_and(x.is_nonnegative for x in diagonal_entries)
|
|
|
|
def atoms(self, *types):
|
|
"""Returns the atoms that form the current object.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> from sympy.matrices import Matrix
|
|
>>> Matrix([[x]])
|
|
Matrix([[x]])
|
|
>>> _.atoms()
|
|
{x}
|
|
>>> Matrix([[x, y], [y, x]])
|
|
Matrix([
|
|
[x, y],
|
|
[y, x]])
|
|
>>> _.atoms()
|
|
{x, y}
|
|
"""
|
|
|
|
types = tuple(t if isinstance(t, type) else type(t) for t in types)
|
|
if not types:
|
|
types = (Atom,)
|
|
return self._eval_atoms(*types)
|
|
|
|
@property
|
|
def free_symbols(self):
|
|
"""Returns the free symbols within the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x
|
|
>>> from sympy.matrices import Matrix
|
|
>>> Matrix([[x], [1]]).free_symbols
|
|
{x}
|
|
"""
|
|
return self._eval_free_symbols()
|
|
|
|
def has(self, *patterns):
|
|
"""Test whether any subexpression matches any of the patterns.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, SparseMatrix, Float
|
|
>>> from sympy.abc import x, y
|
|
>>> A = Matrix(((1, x), (0.2, 3)))
|
|
>>> B = SparseMatrix(((1, x), (0.2, 3)))
|
|
>>> A.has(x)
|
|
True
|
|
>>> A.has(y)
|
|
False
|
|
>>> A.has(Float)
|
|
True
|
|
>>> B.has(x)
|
|
True
|
|
>>> B.has(y)
|
|
False
|
|
>>> B.has(Float)
|
|
True
|
|
"""
|
|
return self._eval_has(*patterns)
|
|
|
|
def is_anti_symmetric(self, simplify=True):
|
|
"""Check if matrix M is an antisymmetric matrix,
|
|
that is, M is a square matrix with all M[i, j] == -M[j, i].
|
|
|
|
When ``simplify=True`` (default), the sum M[i, j] + M[j, i] is
|
|
simplified before testing to see if it is zero. By default,
|
|
the SymPy simplify function is used. To use a custom function
|
|
set simplify to a function that accepts a single argument which
|
|
returns a simplified expression. To skip simplification, set
|
|
simplify to False but note that although this will be faster,
|
|
it may induce false negatives.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, symbols
|
|
>>> m = Matrix(2, 2, [0, 1, -1, 0])
|
|
>>> m
|
|
Matrix([
|
|
[ 0, 1],
|
|
[-1, 0]])
|
|
>>> m.is_anti_symmetric()
|
|
True
|
|
>>> x, y = symbols('x y')
|
|
>>> m = Matrix(2, 3, [0, 0, x, -y, 0, 0])
|
|
>>> m
|
|
Matrix([
|
|
[ 0, 0, x],
|
|
[-y, 0, 0]])
|
|
>>> m.is_anti_symmetric()
|
|
False
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> m = Matrix(3, 3, [0, x**2 + 2*x + 1, y,
|
|
... -(x + 1)**2 , 0, x*y,
|
|
... -y, -x*y, 0])
|
|
|
|
Simplification of matrix elements is done by default so even
|
|
though two elements which should be equal and opposite wouldn't
|
|
pass an equality test, the matrix is still reported as
|
|
anti-symmetric:
|
|
|
|
>>> m[0, 1] == -m[1, 0]
|
|
False
|
|
>>> m.is_anti_symmetric()
|
|
True
|
|
|
|
If 'simplify=False' is used for the case when a Matrix is already
|
|
simplified, this will speed things up. Here, we see that without
|
|
simplification the matrix does not appear anti-symmetric:
|
|
|
|
>>> m.is_anti_symmetric(simplify=False)
|
|
False
|
|
|
|
But if the matrix were already expanded, then it would appear
|
|
anti-symmetric and simplification in the is_anti_symmetric routine
|
|
is not needed:
|
|
|
|
>>> m = m.expand()
|
|
>>> m.is_anti_symmetric(simplify=False)
|
|
True
|
|
"""
|
|
# accept custom simplification
|
|
simpfunc = simplify
|
|
if not isfunction(simplify):
|
|
simpfunc = _simplify if simplify else lambda x: x
|
|
|
|
if not self.is_square:
|
|
return False
|
|
return self._eval_is_anti_symmetric(simpfunc)
|
|
|
|
def is_diagonal(self):
|
|
"""Check if matrix is diagonal,
|
|
that is matrix in which the entries outside the main diagonal are all zero.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, diag
|
|
>>> m = Matrix(2, 2, [1, 0, 0, 2])
|
|
>>> m
|
|
Matrix([
|
|
[1, 0],
|
|
[0, 2]])
|
|
>>> m.is_diagonal()
|
|
True
|
|
|
|
>>> m = Matrix(2, 2, [1, 1, 0, 2])
|
|
>>> m
|
|
Matrix([
|
|
[1, 1],
|
|
[0, 2]])
|
|
>>> m.is_diagonal()
|
|
False
|
|
|
|
>>> m = diag(1, 2, 3)
|
|
>>> m
|
|
Matrix([
|
|
[1, 0, 0],
|
|
[0, 2, 0],
|
|
[0, 0, 3]])
|
|
>>> m.is_diagonal()
|
|
True
|
|
|
|
See Also
|
|
========
|
|
|
|
is_lower
|
|
is_upper
|
|
sympy.matrices.matrices.MatrixEigen.is_diagonalizable
|
|
diagonalize
|
|
"""
|
|
return self._eval_is_diagonal()
|
|
|
|
@property
|
|
def is_weakly_diagonally_dominant(self):
|
|
r"""Tests if the matrix is row weakly diagonally dominant.
|
|
|
|
Explanation
|
|
===========
|
|
|
|
A $n, n$ matrix $A$ is row weakly diagonally dominant if
|
|
|
|
.. math::
|
|
\left|A_{i, i}\right| \ge \sum_{j = 0, j \neq i}^{n-1}
|
|
\left|A_{i, j}\right| \quad {\text{for all }}
|
|
i \in \{ 0, ..., n-1 \}
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> A = Matrix([[3, -2, 1], [1, -3, 2], [-1, 2, 4]])
|
|
>>> A.is_weakly_diagonally_dominant
|
|
True
|
|
|
|
>>> A = Matrix([[-2, 2, 1], [1, 3, 2], [1, -2, 0]])
|
|
>>> A.is_weakly_diagonally_dominant
|
|
False
|
|
|
|
>>> A = Matrix([[-4, 2, 1], [1, 6, 2], [1, -2, 5]])
|
|
>>> A.is_weakly_diagonally_dominant
|
|
True
|
|
|
|
Notes
|
|
=====
|
|
|
|
If you want to test whether a matrix is column diagonally
|
|
dominant, you can apply the test after transposing the matrix.
|
|
"""
|
|
if not self.is_square:
|
|
return False
|
|
|
|
rows, cols = self.shape
|
|
|
|
def test_row(i):
|
|
summation = self.zero
|
|
for j in range(cols):
|
|
if i != j:
|
|
summation += Abs(self[i, j])
|
|
return (Abs(self[i, i]) - summation).is_nonnegative
|
|
|
|
return fuzzy_and(test_row(i) for i in range(rows))
|
|
|
|
@property
|
|
def is_strongly_diagonally_dominant(self):
|
|
r"""Tests if the matrix is row strongly diagonally dominant.
|
|
|
|
Explanation
|
|
===========
|
|
|
|
A $n, n$ matrix $A$ is row strongly diagonally dominant if
|
|
|
|
.. math::
|
|
\left|A_{i, i}\right| > \sum_{j = 0, j \neq i}^{n-1}
|
|
\left|A_{i, j}\right| \quad {\text{for all }}
|
|
i \in \{ 0, ..., n-1 \}
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> A = Matrix([[3, -2, 1], [1, -3, 2], [-1, 2, 4]])
|
|
>>> A.is_strongly_diagonally_dominant
|
|
False
|
|
|
|
>>> A = Matrix([[-2, 2, 1], [1, 3, 2], [1, -2, 0]])
|
|
>>> A.is_strongly_diagonally_dominant
|
|
False
|
|
|
|
>>> A = Matrix([[-4, 2, 1], [1, 6, 2], [1, -2, 5]])
|
|
>>> A.is_strongly_diagonally_dominant
|
|
True
|
|
|
|
Notes
|
|
=====
|
|
|
|
If you want to test whether a matrix is column diagonally
|
|
dominant, you can apply the test after transposing the matrix.
|
|
"""
|
|
if not self.is_square:
|
|
return False
|
|
|
|
rows, cols = self.shape
|
|
|
|
def test_row(i):
|
|
summation = self.zero
|
|
for j in range(cols):
|
|
if i != j:
|
|
summation += Abs(self[i, j])
|
|
return (Abs(self[i, i]) - summation).is_positive
|
|
|
|
return fuzzy_and(test_row(i) for i in range(rows))
|
|
|
|
@property
|
|
def is_hermitian(self):
|
|
"""Checks if the matrix is Hermitian.
|
|
|
|
In a Hermitian matrix element i,j is the complex conjugate of
|
|
element j,i.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> from sympy import I
|
|
>>> from sympy.abc import x
|
|
>>> a = Matrix([[1, I], [-I, 1]])
|
|
>>> a
|
|
Matrix([
|
|
[ 1, I],
|
|
[-I, 1]])
|
|
>>> a.is_hermitian
|
|
True
|
|
>>> a[0, 0] = 2*I
|
|
>>> a.is_hermitian
|
|
False
|
|
>>> a[0, 0] = x
|
|
>>> a.is_hermitian
|
|
>>> a[0, 1] = a[1, 0]*I
|
|
>>> a.is_hermitian
|
|
False
|
|
"""
|
|
if not self.is_square:
|
|
return False
|
|
|
|
return self._eval_is_matrix_hermitian(_simplify)
|
|
|
|
@property
|
|
def is_Identity(self) -> FuzzyBool:
|
|
if not self.is_square:
|
|
return False
|
|
return self._eval_is_Identity()
|
|
|
|
@property
|
|
def is_lower_hessenberg(self):
|
|
r"""Checks if the matrix is in the lower-Hessenberg form.
|
|
|
|
The lower hessenberg matrix has zero entries
|
|
above the first superdiagonal.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> a = Matrix([[1, 2, 0, 0], [5, 2, 3, 0], [3, 4, 3, 7], [5, 6, 1, 1]])
|
|
>>> a
|
|
Matrix([
|
|
[1, 2, 0, 0],
|
|
[5, 2, 3, 0],
|
|
[3, 4, 3, 7],
|
|
[5, 6, 1, 1]])
|
|
>>> a.is_lower_hessenberg
|
|
True
|
|
|
|
See Also
|
|
========
|
|
|
|
is_upper_hessenberg
|
|
is_lower
|
|
"""
|
|
return self._eval_is_lower_hessenberg()
|
|
|
|
@property
|
|
def is_lower(self):
|
|
"""Check if matrix is a lower triangular matrix. True can be returned
|
|
even if the matrix is not square.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(2, 2, [1, 0, 0, 1])
|
|
>>> m
|
|
Matrix([
|
|
[1, 0],
|
|
[0, 1]])
|
|
>>> m.is_lower
|
|
True
|
|
|
|
>>> m = Matrix(4, 3, [0, 0, 0, 2, 0, 0, 1, 4 , 0, 6, 6, 5])
|
|
>>> m
|
|
Matrix([
|
|
[0, 0, 0],
|
|
[2, 0, 0],
|
|
[1, 4, 0],
|
|
[6, 6, 5]])
|
|
>>> m.is_lower
|
|
True
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> m = Matrix(2, 2, [x**2 + y, y**2 + x, 0, x + y])
|
|
>>> m
|
|
Matrix([
|
|
[x**2 + y, x + y**2],
|
|
[ 0, x + y]])
|
|
>>> m.is_lower
|
|
False
|
|
|
|
See Also
|
|
========
|
|
|
|
is_upper
|
|
is_diagonal
|
|
is_lower_hessenberg
|
|
"""
|
|
return self._eval_is_lower()
|
|
|
|
@property
|
|
def is_square(self):
|
|
"""Checks if a matrix is square.
|
|
|
|
A matrix is square if the number of rows equals the number of columns.
|
|
The empty matrix is square by definition, since the number of rows and
|
|
the number of columns are both zero.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> a = Matrix([[1, 2, 3], [4, 5, 6]])
|
|
>>> b = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
|
|
>>> c = Matrix([])
|
|
>>> a.is_square
|
|
False
|
|
>>> b.is_square
|
|
True
|
|
>>> c.is_square
|
|
True
|
|
"""
|
|
return self.rows == self.cols
|
|
|
|
def is_symbolic(self):
|
|
"""Checks if any elements contain Symbols.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> from sympy.abc import x, y
|
|
>>> M = Matrix([[x, y], [1, 0]])
|
|
>>> M.is_symbolic()
|
|
True
|
|
|
|
"""
|
|
return self._eval_is_symbolic()
|
|
|
|
def is_symmetric(self, simplify=True):
|
|
"""Check if matrix is symmetric matrix,
|
|
that is square matrix and is equal to its transpose.
|
|
|
|
By default, simplifications occur before testing symmetry.
|
|
They can be skipped using 'simplify=False'; while speeding things a bit,
|
|
this may however induce false negatives.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(2, 2, [0, 1, 1, 2])
|
|
>>> m
|
|
Matrix([
|
|
[0, 1],
|
|
[1, 2]])
|
|
>>> m.is_symmetric()
|
|
True
|
|
|
|
>>> m = Matrix(2, 2, [0, 1, 2, 0])
|
|
>>> m
|
|
Matrix([
|
|
[0, 1],
|
|
[2, 0]])
|
|
>>> m.is_symmetric()
|
|
False
|
|
|
|
>>> m = Matrix(2, 3, [0, 0, 0, 0, 0, 0])
|
|
>>> m
|
|
Matrix([
|
|
[0, 0, 0],
|
|
[0, 0, 0]])
|
|
>>> m.is_symmetric()
|
|
False
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> m = Matrix(3, 3, [1, x**2 + 2*x + 1, y, (x + 1)**2 , 2, 0, y, 0, 3])
|
|
>>> m
|
|
Matrix([
|
|
[ 1, x**2 + 2*x + 1, y],
|
|
[(x + 1)**2, 2, 0],
|
|
[ y, 0, 3]])
|
|
>>> m.is_symmetric()
|
|
True
|
|
|
|
If the matrix is already simplified, you may speed-up is_symmetric()
|
|
test by using 'simplify=False'.
|
|
|
|
>>> bool(m.is_symmetric(simplify=False))
|
|
False
|
|
>>> m1 = m.expand()
|
|
>>> m1.is_symmetric(simplify=False)
|
|
True
|
|
"""
|
|
simpfunc = simplify
|
|
if not isfunction(simplify):
|
|
simpfunc = _simplify if simplify else lambda x: x
|
|
|
|
if not self.is_square:
|
|
return False
|
|
|
|
return self._eval_is_symmetric(simpfunc)
|
|
|
|
@property
|
|
def is_upper_hessenberg(self):
|
|
"""Checks if the matrix is the upper-Hessenberg form.
|
|
|
|
The upper hessenberg matrix has zero entries
|
|
below the first subdiagonal.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> a = Matrix([[1, 4, 2, 3], [3, 4, 1, 7], [0, 2, 3, 4], [0, 0, 1, 3]])
|
|
>>> a
|
|
Matrix([
|
|
[1, 4, 2, 3],
|
|
[3, 4, 1, 7],
|
|
[0, 2, 3, 4],
|
|
[0, 0, 1, 3]])
|
|
>>> a.is_upper_hessenberg
|
|
True
|
|
|
|
See Also
|
|
========
|
|
|
|
is_lower_hessenberg
|
|
is_upper
|
|
"""
|
|
return self._eval_is_upper_hessenberg()
|
|
|
|
@property
|
|
def is_upper(self):
|
|
"""Check if matrix is an upper triangular matrix. True can be returned
|
|
even if the matrix is not square.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(2, 2, [1, 0, 0, 1])
|
|
>>> m
|
|
Matrix([
|
|
[1, 0],
|
|
[0, 1]])
|
|
>>> m.is_upper
|
|
True
|
|
|
|
>>> m = Matrix(4, 3, [5, 1, 9, 0, 4 , 6, 0, 0, 5, 0, 0, 0])
|
|
>>> m
|
|
Matrix([
|
|
[5, 1, 9],
|
|
[0, 4, 6],
|
|
[0, 0, 5],
|
|
[0, 0, 0]])
|
|
>>> m.is_upper
|
|
True
|
|
|
|
>>> m = Matrix(2, 3, [4, 2, 5, 6, 1, 1])
|
|
>>> m
|
|
Matrix([
|
|
[4, 2, 5],
|
|
[6, 1, 1]])
|
|
>>> m.is_upper
|
|
False
|
|
|
|
See Also
|
|
========
|
|
|
|
is_lower
|
|
is_diagonal
|
|
is_upper_hessenberg
|
|
"""
|
|
return all(self[i, j].is_zero
|
|
for i in range(1, self.rows)
|
|
for j in range(min(i, self.cols)))
|
|
|
|
@property
|
|
def is_zero_matrix(self):
|
|
"""Checks if a matrix is a zero matrix.
|
|
|
|
A matrix is zero if every element is zero. A matrix need not be square
|
|
to be considered zero. The empty matrix is zero by the principle of
|
|
vacuous truth. For a matrix that may or may not be zero (e.g.
|
|
contains a symbol), this will be None
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, zeros
|
|
>>> from sympy.abc import x
|
|
>>> a = Matrix([[0, 0], [0, 0]])
|
|
>>> b = zeros(3, 4)
|
|
>>> c = Matrix([[0, 1], [0, 0]])
|
|
>>> d = Matrix([])
|
|
>>> e = Matrix([[x, 0], [0, 0]])
|
|
>>> a.is_zero_matrix
|
|
True
|
|
>>> b.is_zero_matrix
|
|
True
|
|
>>> c.is_zero_matrix
|
|
False
|
|
>>> d.is_zero_matrix
|
|
True
|
|
>>> e.is_zero_matrix
|
|
"""
|
|
return self._eval_is_zero_matrix()
|
|
|
|
def values(self):
|
|
"""Return non-zero values of self."""
|
|
return self._eval_values()
|
|
|
|
|
|
class MatrixOperations(MatrixRequired):
|
|
"""Provides basic matrix shape and elementwise
|
|
operations. Should not be instantiated directly."""
|
|
|
|
def _eval_adjoint(self):
|
|
return self.transpose().conjugate()
|
|
|
|
def _eval_applyfunc(self, f):
|
|
out = self._new(self.rows, self.cols, [f(x) for x in self])
|
|
return out
|
|
|
|
def _eval_as_real_imag(self): # type: ignore
|
|
from sympy.functions.elementary.complexes import re, im
|
|
|
|
return (self.applyfunc(re), self.applyfunc(im))
|
|
|
|
def _eval_conjugate(self):
|
|
return self.applyfunc(lambda x: x.conjugate())
|
|
|
|
def _eval_permute_cols(self, perm):
|
|
# apply the permutation to a list
|
|
mapping = list(perm)
|
|
|
|
def entry(i, j):
|
|
return self[i, mapping[j]]
|
|
|
|
return self._new(self.rows, self.cols, entry)
|
|
|
|
def _eval_permute_rows(self, perm):
|
|
# apply the permutation to a list
|
|
mapping = list(perm)
|
|
|
|
def entry(i, j):
|
|
return self[mapping[i], j]
|
|
|
|
return self._new(self.rows, self.cols, entry)
|
|
|
|
def _eval_trace(self):
|
|
return sum(self[i, i] for i in range(self.rows))
|
|
|
|
def _eval_transpose(self):
|
|
return self._new(self.cols, self.rows, lambda i, j: self[j, i])
|
|
|
|
def adjoint(self):
|
|
"""Conjugate transpose or Hermitian conjugation."""
|
|
return self._eval_adjoint()
|
|
|
|
def applyfunc(self, f):
|
|
"""Apply a function to each element of the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> m = Matrix(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.")
|
|
|
|
return self._eval_applyfunc(f)
|
|
|
|
def as_real_imag(self, deep=True, **hints):
|
|
"""Returns a tuple containing the (real, imaginary) part of matrix."""
|
|
# XXX: Ignoring deep and hints...
|
|
return self._eval_as_real_imag()
|
|
|
|
def conjugate(self):
|
|
"""Return the by-element conjugation.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import SparseMatrix
|
|
>>> from sympy import I
|
|
>>> a = SparseMatrix(((1, 2 + I), (3, 4), (I, -I)))
|
|
>>> a
|
|
Matrix([
|
|
[1, 2 + I],
|
|
[3, 4],
|
|
[I, -I]])
|
|
>>> a.C
|
|
Matrix([
|
|
[ 1, 2 - I],
|
|
[ 3, 4],
|
|
[-I, I]])
|
|
|
|
See Also
|
|
========
|
|
|
|
transpose: Matrix transposition
|
|
H: Hermite conjugation
|
|
sympy.matrices.matrices.MatrixBase.D: Dirac conjugation
|
|
"""
|
|
return self._eval_conjugate()
|
|
|
|
def doit(self, **kwargs):
|
|
return self.applyfunc(lambda x: x.doit())
|
|
|
|
def evalf(self, n=15, subs=None, maxn=100, chop=False, strict=False, quad=None, verbose=False):
|
|
"""Apply evalf() to each element of self."""
|
|
options = {'subs':subs, 'maxn':maxn, 'chop':chop, 'strict':strict,
|
|
'quad':quad, 'verbose':verbose}
|
|
return self.applyfunc(lambda i: i.evalf(n, **options))
|
|
|
|
def expand(self, deep=True, modulus=None, power_base=True, power_exp=True,
|
|
mul=True, log=True, multinomial=True, basic=True, **hints):
|
|
"""Apply core.function.expand to each entry of the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x
|
|
>>> from sympy.matrices import Matrix
|
|
>>> Matrix(1, 1, [x*(x+1)])
|
|
Matrix([[x*(x + 1)]])
|
|
>>> _.expand()
|
|
Matrix([[x**2 + x]])
|
|
|
|
"""
|
|
return self.applyfunc(lambda x: x.expand(
|
|
deep, modulus, power_base, power_exp, mul, log, multinomial, basic,
|
|
**hints))
|
|
|
|
@property
|
|
def H(self):
|
|
"""Return Hermite conjugate.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, I
|
|
>>> m = Matrix((0, 1 + I, 2, 3))
|
|
>>> m
|
|
Matrix([
|
|
[ 0],
|
|
[1 + I],
|
|
[ 2],
|
|
[ 3]])
|
|
>>> m.H
|
|
Matrix([[0, 1 - I, 2, 3]])
|
|
|
|
See Also
|
|
========
|
|
|
|
conjugate: By-element conjugation
|
|
sympy.matrices.matrices.MatrixBase.D: Dirac conjugation
|
|
"""
|
|
return self.T.C
|
|
|
|
def permute(self, perm, orientation='rows', direction='forward'):
|
|
r"""Permute the rows or columns of a matrix by the given list of
|
|
swaps.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
perm : Permutation, list, or list of lists
|
|
A representation for the permutation.
|
|
|
|
If it is ``Permutation``, it is used directly with some
|
|
resizing with respect to the matrix size.
|
|
|
|
If it is specified as list of lists,
|
|
(e.g., ``[[0, 1], [0, 2]]``), then the permutation is formed
|
|
from applying the product of cycles. The direction how the
|
|
cyclic product is applied is described in below.
|
|
|
|
If it is specified as a list, the list should represent
|
|
an array form of a permutation. (e.g., ``[1, 2, 0]``) which
|
|
would would form the swapping function
|
|
`0 \mapsto 1, 1 \mapsto 2, 2\mapsto 0`.
|
|
|
|
orientation : 'rows', 'cols'
|
|
A flag to control whether to permute the rows or the columns
|
|
|
|
direction : 'forward', 'backward'
|
|
A flag to control whether to apply the permutations from
|
|
the start of the list first, or from the back of the list
|
|
first.
|
|
|
|
For example, if the permutation specification is
|
|
``[[0, 1], [0, 2]]``,
|
|
|
|
If the flag is set to ``'forward'``, the cycle would be
|
|
formed as `0 \mapsto 2, 2 \mapsto 1, 1 \mapsto 0`.
|
|
|
|
If the flag is set to ``'backward'``, the cycle would be
|
|
formed as `0 \mapsto 1, 1 \mapsto 2, 2 \mapsto 0`.
|
|
|
|
If the argument ``perm`` is not in a form of list of lists,
|
|
this flag takes no effect.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import eye
|
|
>>> M = eye(3)
|
|
>>> M.permute([[0, 1], [0, 2]], orientation='rows', direction='forward')
|
|
Matrix([
|
|
[0, 0, 1],
|
|
[1, 0, 0],
|
|
[0, 1, 0]])
|
|
|
|
>>> from sympy.matrices import eye
|
|
>>> M = eye(3)
|
|
>>> M.permute([[0, 1], [0, 2]], orientation='rows', direction='backward')
|
|
Matrix([
|
|
[0, 1, 0],
|
|
[0, 0, 1],
|
|
[1, 0, 0]])
|
|
|
|
Notes
|
|
=====
|
|
|
|
If a bijective function
|
|
`\sigma : \mathbb{N}_0 \rightarrow \mathbb{N}_0` denotes the
|
|
permutation.
|
|
|
|
If the matrix `A` is the matrix to permute, represented as
|
|
a horizontal or a vertical stack of vectors:
|
|
|
|
.. math::
|
|
A =
|
|
\begin{bmatrix}
|
|
a_0 \\ a_1 \\ \vdots \\ a_{n-1}
|
|
\end{bmatrix} =
|
|
\begin{bmatrix}
|
|
\alpha_0 & \alpha_1 & \cdots & \alpha_{n-1}
|
|
\end{bmatrix}
|
|
|
|
If the matrix `B` is the result, the permutation of matrix rows
|
|
is defined as:
|
|
|
|
.. math::
|
|
B := \begin{bmatrix}
|
|
a_{\sigma(0)} \\ a_{\sigma(1)} \\ \vdots \\ a_{\sigma(n-1)}
|
|
\end{bmatrix}
|
|
|
|
And the permutation of matrix columns is defined as:
|
|
|
|
.. math::
|
|
B := \begin{bmatrix}
|
|
\alpha_{\sigma(0)} & \alpha_{\sigma(1)} &
|
|
\cdots & \alpha_{\sigma(n-1)}
|
|
\end{bmatrix}
|
|
"""
|
|
from sympy.combinatorics import Permutation
|
|
|
|
# allow british variants and `columns`
|
|
if direction == 'forwards':
|
|
direction = 'forward'
|
|
if direction == 'backwards':
|
|
direction = 'backward'
|
|
if orientation == 'columns':
|
|
orientation = 'cols'
|
|
|
|
if direction not in ('forward', 'backward'):
|
|
raise TypeError("direction='{}' is an invalid kwarg. "
|
|
"Try 'forward' or 'backward'".format(direction))
|
|
if orientation not in ('rows', 'cols'):
|
|
raise TypeError("orientation='{}' is an invalid kwarg. "
|
|
"Try 'rows' or 'cols'".format(orientation))
|
|
|
|
if not isinstance(perm, (Permutation, Iterable)):
|
|
raise ValueError(
|
|
"{} must be a list, a list of lists, "
|
|
"or a SymPy permutation object.".format(perm))
|
|
|
|
# ensure all swaps are in range
|
|
max_index = self.rows if orientation == 'rows' else self.cols
|
|
if not all(0 <= t <= max_index for t in flatten(list(perm))):
|
|
raise IndexError("`swap` indices out of range.")
|
|
|
|
if perm and not isinstance(perm, Permutation) and \
|
|
isinstance(perm[0], Iterable):
|
|
if direction == 'forward':
|
|
perm = list(reversed(perm))
|
|
perm = Permutation(perm, size=max_index+1)
|
|
else:
|
|
perm = Permutation(perm, size=max_index+1)
|
|
|
|
if orientation == 'rows':
|
|
return self._eval_permute_rows(perm)
|
|
if orientation == 'cols':
|
|
return self._eval_permute_cols(perm)
|
|
|
|
def permute_cols(self, swaps, direction='forward'):
|
|
"""Alias for
|
|
``self.permute(swaps, orientation='cols', direction=direction)``
|
|
|
|
See Also
|
|
========
|
|
|
|
permute
|
|
"""
|
|
return self.permute(swaps, orientation='cols', direction=direction)
|
|
|
|
def permute_rows(self, swaps, direction='forward'):
|
|
"""Alias for
|
|
``self.permute(swaps, orientation='rows', direction=direction)``
|
|
|
|
See Also
|
|
========
|
|
|
|
permute
|
|
"""
|
|
return self.permute(swaps, orientation='rows', direction=direction)
|
|
|
|
def refine(self, assumptions=True):
|
|
"""Apply refine to each element of the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Symbol, Matrix, Abs, sqrt, Q
|
|
>>> x = Symbol('x')
|
|
>>> Matrix([[Abs(x)**2, sqrt(x**2)],[sqrt(x**2), Abs(x)**2]])
|
|
Matrix([
|
|
[ Abs(x)**2, sqrt(x**2)],
|
|
[sqrt(x**2), Abs(x)**2]])
|
|
>>> _.refine(Q.real(x))
|
|
Matrix([
|
|
[ x**2, Abs(x)],
|
|
[Abs(x), x**2]])
|
|
|
|
"""
|
|
return self.applyfunc(lambda x: refine(x, assumptions))
|
|
|
|
def replace(self, F, G, map=False, simultaneous=True, exact=None):
|
|
"""Replaces Function F in Matrix entries with Function G.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import symbols, Function, Matrix
|
|
>>> F, G = symbols('F, G', cls=Function)
|
|
>>> M = Matrix(2, 2, lambda i, j: F(i+j)) ; M
|
|
Matrix([
|
|
[F(0), F(1)],
|
|
[F(1), F(2)]])
|
|
>>> N = M.replace(F,G)
|
|
>>> N
|
|
Matrix([
|
|
[G(0), G(1)],
|
|
[G(1), G(2)]])
|
|
"""
|
|
return self.applyfunc(
|
|
lambda x: x.replace(F, G, map=map, simultaneous=simultaneous, exact=exact))
|
|
|
|
def rot90(self, k=1):
|
|
"""Rotates Matrix by 90 degrees
|
|
|
|
Parameters
|
|
==========
|
|
|
|
k : int
|
|
Specifies how many times the matrix is rotated by 90 degrees
|
|
(clockwise when positive, counter-clockwise when negative).
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, symbols
|
|
>>> A = Matrix(2, 2, symbols('a:d'))
|
|
>>> A
|
|
Matrix([
|
|
[a, b],
|
|
[c, d]])
|
|
|
|
Rotating the matrix clockwise one time:
|
|
|
|
>>> A.rot90(1)
|
|
Matrix([
|
|
[c, a],
|
|
[d, b]])
|
|
|
|
Rotating the matrix anticlockwise two times:
|
|
|
|
>>> A.rot90(-2)
|
|
Matrix([
|
|
[d, c],
|
|
[b, a]])
|
|
"""
|
|
|
|
mod = k%4
|
|
if mod == 0:
|
|
return self
|
|
if mod == 1:
|
|
return self[::-1, ::].T
|
|
if mod == 2:
|
|
return self[::-1, ::-1]
|
|
if mod == 3:
|
|
return self[::, ::-1].T
|
|
|
|
def simplify(self, **kwargs):
|
|
"""Apply simplify to each element of the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> from sympy import sin, cos
|
|
>>> from sympy.matrices import SparseMatrix
|
|
>>> SparseMatrix(1, 1, [x*sin(y)**2 + x*cos(y)**2])
|
|
Matrix([[x*sin(y)**2 + x*cos(y)**2]])
|
|
>>> _.simplify()
|
|
Matrix([[x]])
|
|
"""
|
|
return self.applyfunc(lambda x: x.simplify(**kwargs))
|
|
|
|
def subs(self, *args, **kwargs): # should mirror core.basic.subs
|
|
"""Return a new matrix with subs applied to each entry.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> from sympy.matrices import SparseMatrix, Matrix
|
|
>>> SparseMatrix(1, 1, [x])
|
|
Matrix([[x]])
|
|
>>> _.subs(x, y)
|
|
Matrix([[y]])
|
|
>>> Matrix(_).subs(y, x)
|
|
Matrix([[x]])
|
|
"""
|
|
|
|
if len(args) == 1 and not isinstance(args[0], (dict, set)) and iter(args[0]) and not is_sequence(args[0]):
|
|
args = (list(args[0]),)
|
|
|
|
return self.applyfunc(lambda x: x.subs(*args, **kwargs))
|
|
|
|
def trace(self):
|
|
"""
|
|
Returns the trace of a square matrix i.e. the sum of the
|
|
diagonal elements.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> A = Matrix(2, 2, [1, 2, 3, 4])
|
|
>>> A.trace()
|
|
5
|
|
|
|
"""
|
|
if self.rows != self.cols:
|
|
raise NonSquareMatrixError()
|
|
return self._eval_trace()
|
|
|
|
def transpose(self):
|
|
"""
|
|
Returns the transpose of the matrix.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix
|
|
>>> A = Matrix(2, 2, [1, 2, 3, 4])
|
|
>>> A.transpose()
|
|
Matrix([
|
|
[1, 3],
|
|
[2, 4]])
|
|
|
|
>>> from sympy import Matrix, I
|
|
>>> m=Matrix(((1, 2+I), (3, 4)))
|
|
>>> m
|
|
Matrix([
|
|
[1, 2 + I],
|
|
[3, 4]])
|
|
>>> m.transpose()
|
|
Matrix([
|
|
[ 1, 3],
|
|
[2 + I, 4]])
|
|
>>> m.T == m.transpose()
|
|
True
|
|
|
|
See Also
|
|
========
|
|
|
|
conjugate: By-element conjugation
|
|
|
|
"""
|
|
return self._eval_transpose()
|
|
|
|
@property
|
|
def T(self):
|
|
'''Matrix transposition'''
|
|
return self.transpose()
|
|
|
|
@property
|
|
def C(self):
|
|
'''By-element conjugation'''
|
|
return self.conjugate()
|
|
|
|
def n(self, *args, **kwargs):
|
|
"""Apply evalf() to each element of self."""
|
|
return self.evalf(*args, **kwargs)
|
|
|
|
def xreplace(self, rule): # should mirror core.basic.xreplace
|
|
"""Return a new matrix with xreplace applied to each entry.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.abc import x, y
|
|
>>> from sympy.matrices import SparseMatrix, Matrix
|
|
>>> SparseMatrix(1, 1, [x])
|
|
Matrix([[x]])
|
|
>>> _.xreplace({x: y})
|
|
Matrix([[y]])
|
|
>>> Matrix(_).xreplace({y: x})
|
|
Matrix([[x]])
|
|
"""
|
|
return self.applyfunc(lambda x: x.xreplace(rule))
|
|
|
|
def _eval_simplify(self, **kwargs):
|
|
# XXX: We can't use self.simplify here as mutable subclasses will
|
|
# override simplify and have it return None
|
|
return MatrixOperations.simplify(self, **kwargs)
|
|
|
|
def _eval_trigsimp(self, **opts):
|
|
from sympy.simplify import trigsimp
|
|
return self.applyfunc(lambda x: trigsimp(x, **opts))
|
|
|
|
def upper_triangular(self, k=0):
|
|
"""returns the elements on and above the kth diagonal of a matrix.
|
|
If k is not specified then simply returns upper-triangular portion
|
|
of a matrix
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import ones
|
|
>>> A = ones(4)
|
|
>>> A.upper_triangular()
|
|
Matrix([
|
|
[1, 1, 1, 1],
|
|
[0, 1, 1, 1],
|
|
[0, 0, 1, 1],
|
|
[0, 0, 0, 1]])
|
|
|
|
>>> A.upper_triangular(2)
|
|
Matrix([
|
|
[0, 0, 1, 1],
|
|
[0, 0, 0, 1],
|
|
[0, 0, 0, 0],
|
|
[0, 0, 0, 0]])
|
|
|
|
>>> A.upper_triangular(-1)
|
|
Matrix([
|
|
[1, 1, 1, 1],
|
|
[1, 1, 1, 1],
|
|
[0, 1, 1, 1],
|
|
[0, 0, 1, 1]])
|
|
|
|
"""
|
|
|
|
def entry(i, j):
|
|
return self[i, j] if i + k <= j else self.zero
|
|
|
|
return self._new(self.rows, self.cols, entry)
|
|
|
|
|
|
def lower_triangular(self, k=0):
|
|
"""returns the elements on and below the kth diagonal of a matrix.
|
|
If k is not specified then simply returns lower-triangular portion
|
|
of a matrix
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import ones
|
|
>>> A = ones(4)
|
|
>>> A.lower_triangular()
|
|
Matrix([
|
|
[1, 0, 0, 0],
|
|
[1, 1, 0, 0],
|
|
[1, 1, 1, 0],
|
|
[1, 1, 1, 1]])
|
|
|
|
>>> A.lower_triangular(-2)
|
|
Matrix([
|
|
[0, 0, 0, 0],
|
|
[0, 0, 0, 0],
|
|
[1, 0, 0, 0],
|
|
[1, 1, 0, 0]])
|
|
|
|
>>> A.lower_triangular(1)
|
|
Matrix([
|
|
[1, 1, 0, 0],
|
|
[1, 1, 1, 0],
|
|
[1, 1, 1, 1],
|
|
[1, 1, 1, 1]])
|
|
|
|
"""
|
|
|
|
def entry(i, j):
|
|
return self[i, j] if i + k >= j else self.zero
|
|
|
|
return self._new(self.rows, self.cols, entry)
|
|
|
|
|
|
|
|
class MatrixArithmetic(MatrixRequired):
|
|
"""Provides basic matrix arithmetic operations.
|
|
Should not be instantiated directly."""
|
|
|
|
_op_priority = 10.01
|
|
|
|
def _eval_Abs(self):
|
|
return self._new(self.rows, self.cols, lambda i, j: Abs(self[i, j]))
|
|
|
|
def _eval_add(self, other):
|
|
return self._new(self.rows, self.cols,
|
|
lambda i, j: self[i, j] + other[i, j])
|
|
|
|
def _eval_matrix_mul(self, other):
|
|
def entry(i, j):
|
|
vec = [self[i,k]*other[k,j] for k in range(self.cols)]
|
|
try:
|
|
return 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.
|
|
return reduce(lambda a, b: a + b, vec)
|
|
|
|
return self._new(self.rows, other.cols, entry)
|
|
|
|
def _eval_matrix_mul_elementwise(self, other):
|
|
return self._new(self.rows, self.cols, lambda i, j: self[i,j]*other[i,j])
|
|
|
|
def _eval_matrix_rmul(self, other):
|
|
def entry(i, j):
|
|
return sum(other[i,k]*self[k,j] for k in range(other.cols))
|
|
return self._new(other.rows, self.cols, entry)
|
|
|
|
def _eval_pow_by_recursion(self, num):
|
|
if num == 1:
|
|
return self
|
|
|
|
if num % 2 == 1:
|
|
a, b = self, self._eval_pow_by_recursion(num - 1)
|
|
else:
|
|
a = b = self._eval_pow_by_recursion(num // 2)
|
|
|
|
return a.multiply(b)
|
|
|
|
def _eval_pow_by_cayley(self, exp):
|
|
from sympy.discrete.recurrences import linrec_coeffs
|
|
row = self.shape[0]
|
|
p = self.charpoly()
|
|
|
|
coeffs = (-p).all_coeffs()[1:]
|
|
coeffs = linrec_coeffs(coeffs, exp)
|
|
new_mat = self.eye(row)
|
|
ans = self.zeros(row)
|
|
|
|
for i in range(row):
|
|
ans += coeffs[i]*new_mat
|
|
new_mat *= self
|
|
|
|
return ans
|
|
|
|
def _eval_pow_by_recursion_dotprodsimp(self, num, prevsimp=None):
|
|
if prevsimp is None:
|
|
prevsimp = [True]*len(self)
|
|
|
|
if num == 1:
|
|
return self
|
|
|
|
if num % 2 == 1:
|
|
a, b = self, self._eval_pow_by_recursion_dotprodsimp(num - 1,
|
|
prevsimp=prevsimp)
|
|
else:
|
|
a = b = self._eval_pow_by_recursion_dotprodsimp(num // 2,
|
|
prevsimp=prevsimp)
|
|
|
|
m = a.multiply(b, dotprodsimp=False)
|
|
lenm = len(m)
|
|
elems = [None]*lenm
|
|
|
|
for i in range(lenm):
|
|
if prevsimp[i]:
|
|
elems[i], prevsimp[i] = _dotprodsimp(m[i], withsimp=True)
|
|
else:
|
|
elems[i] = m[i]
|
|
|
|
return m._new(m.rows, m.cols, elems)
|
|
|
|
def _eval_scalar_mul(self, other):
|
|
return self._new(self.rows, self.cols, lambda i, j: self[i,j]*other)
|
|
|
|
def _eval_scalar_rmul(self, other):
|
|
return self._new(self.rows, self.cols, lambda i, j: other*self[i,j])
|
|
|
|
def _eval_Mod(self, other):
|
|
from sympy import Mod
|
|
return self._new(self.rows, self.cols, lambda i, j: Mod(self[i, j], other))
|
|
|
|
# python arithmetic functions
|
|
def __abs__(self):
|
|
"""Returns a new matrix with entry-wise absolute values."""
|
|
return self._eval_Abs()
|
|
|
|
@call_highest_priority('__radd__')
|
|
def __add__(self, other):
|
|
"""Return self + other, raising ShapeError if shapes don't match."""
|
|
if isinstance(other, NDimArray): # Matrix and array addition is currently not implemented
|
|
return NotImplemented
|
|
other = _matrixify(other)
|
|
# matrix-like objects can have shapes. This is
|
|
# our first sanity check.
|
|
if hasattr(other, 'shape'):
|
|
if self.shape != other.shape:
|
|
raise ShapeError("Matrix size mismatch: %s + %s" % (
|
|
self.shape, other.shape))
|
|
|
|
# honest sympy matrices defer to their class's routine
|
|
if getattr(other, 'is_Matrix', False):
|
|
# call the highest-priority class's _eval_add
|
|
a, b = self, other
|
|
if a.__class__ != classof(a, b):
|
|
b, a = a, b
|
|
return a._eval_add(b)
|
|
# Matrix-like objects can be passed to CommonMatrix routines directly.
|
|
if getattr(other, 'is_MatrixLike', False):
|
|
return MatrixArithmetic._eval_add(self, other)
|
|
|
|
raise TypeError('cannot add %s and %s' % (type(self), type(other)))
|
|
|
|
@call_highest_priority('__rtruediv__')
|
|
def __truediv__(self, other):
|
|
return self * (self.one / other)
|
|
|
|
@call_highest_priority('__rmatmul__')
|
|
def __matmul__(self, other):
|
|
other = _matrixify(other)
|
|
if not getattr(other, 'is_Matrix', False) and not getattr(other, 'is_MatrixLike', False):
|
|
return NotImplemented
|
|
|
|
return self.__mul__(other)
|
|
|
|
def __mod__(self, other):
|
|
return self.applyfunc(lambda x: x % other)
|
|
|
|
@call_highest_priority('__rmul__')
|
|
def __mul__(self, other):
|
|
"""Return self*other where other is either a scalar or a matrix
|
|
of compatible dimensions.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> A = Matrix([[1, 2, 3], [4, 5, 6]])
|
|
>>> 2*A == A*2 == Matrix([[2, 4, 6], [8, 10, 12]])
|
|
True
|
|
>>> B = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
|
|
>>> A*B
|
|
Matrix([
|
|
[30, 36, 42],
|
|
[66, 81, 96]])
|
|
>>> B*A
|
|
Traceback (most recent call last):
|
|
...
|
|
ShapeError: Matrices size mismatch.
|
|
>>>
|
|
|
|
See Also
|
|
========
|
|
|
|
matrix_multiply_elementwise
|
|
"""
|
|
|
|
return self.multiply(other)
|
|
|
|
def multiply(self, other, dotprodsimp=None):
|
|
"""Same as __mul__() but with optional simplification.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
dotprodsimp : bool, optional
|
|
Specifies whether intermediate term algebraic simplification is used
|
|
during matrix multiplications to control expression blowup and thus
|
|
speed up calculation. Default is off.
|
|
"""
|
|
|
|
isimpbool = _get_intermediate_simp_bool(False, dotprodsimp)
|
|
other = _matrixify(other)
|
|
# matrix-like objects can have shapes. This is
|
|
# our first sanity check. Double check other is not explicitly not a Matrix.
|
|
if (hasattr(other, 'shape') and len(other.shape) == 2 and
|
|
(getattr(other, 'is_Matrix', True) or
|
|
getattr(other, 'is_MatrixLike', True))):
|
|
if self.shape[1] != other.shape[0]:
|
|
raise ShapeError("Matrix size mismatch: %s * %s." % (
|
|
self.shape, other.shape))
|
|
|
|
# honest sympy matrices defer to their class's routine
|
|
if getattr(other, 'is_Matrix', False):
|
|
m = self._eval_matrix_mul(other)
|
|
if isimpbool:
|
|
return m._new(m.rows, m.cols, [_dotprodsimp(e) for e in m])
|
|
return m
|
|
|
|
# Matrix-like objects can be passed to CommonMatrix routines directly.
|
|
if getattr(other, 'is_MatrixLike', False):
|
|
return MatrixArithmetic._eval_matrix_mul(self, other)
|
|
|
|
# if 'other' is not iterable then scalar multiplication.
|
|
if not isinstance(other, Iterable):
|
|
try:
|
|
return self._eval_scalar_mul(other)
|
|
except TypeError:
|
|
pass
|
|
|
|
return NotImplemented
|
|
|
|
def multiply_elementwise(self, other):
|
|
"""Return the Hadamard product (elementwise product) of A and B
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy.matrices import Matrix
|
|
>>> A = Matrix([[0, 1, 2], [3, 4, 5]])
|
|
>>> B = Matrix([[1, 10, 100], [100, 10, 1]])
|
|
>>> A.multiply_elementwise(B)
|
|
Matrix([
|
|
[ 0, 10, 200],
|
|
[300, 40, 5]])
|
|
|
|
See Also
|
|
========
|
|
|
|
sympy.matrices.matrices.MatrixBase.cross
|
|
sympy.matrices.matrices.MatrixBase.dot
|
|
multiply
|
|
"""
|
|
if self.shape != other.shape:
|
|
raise ShapeError("Matrix shapes must agree {} != {}".format(self.shape, other.shape))
|
|
|
|
return self._eval_matrix_mul_elementwise(other)
|
|
|
|
def __neg__(self):
|
|
return self._eval_scalar_mul(-1)
|
|
|
|
@call_highest_priority('__rpow__')
|
|
def __pow__(self, exp):
|
|
"""Return self**exp a scalar or symbol."""
|
|
|
|
return self.pow(exp)
|
|
|
|
|
|
def pow(self, exp, method=None):
|
|
r"""Return self**exp a scalar or symbol.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
method : multiply, mulsimp, jordan, cayley
|
|
If multiply then it returns exponentiation using recursion.
|
|
If jordan then Jordan form exponentiation will be used.
|
|
If cayley then the exponentiation is done using Cayley-Hamilton
|
|
theorem.
|
|
If mulsimp then the exponentiation is done using recursion
|
|
with dotprodsimp. This specifies whether intermediate term
|
|
algebraic simplification is used during naive matrix power to
|
|
control expression blowup and thus speed up calculation.
|
|
If None, then it heuristically decides which method to use.
|
|
|
|
"""
|
|
|
|
if method is not None and method not in ['multiply', 'mulsimp', 'jordan', 'cayley']:
|
|
raise TypeError('No such method')
|
|
if self.rows != self.cols:
|
|
raise NonSquareMatrixError()
|
|
a = self
|
|
jordan_pow = getattr(a, '_matrix_pow_by_jordan_blocks', None)
|
|
exp = sympify(exp)
|
|
|
|
if exp.is_zero:
|
|
return a._new(a.rows, a.cols, lambda i, j: int(i == j))
|
|
if exp == 1:
|
|
return a
|
|
|
|
diagonal = getattr(a, 'is_diagonal', None)
|
|
if diagonal is not None and diagonal():
|
|
return a._new(a.rows, a.cols, lambda i, j: a[i,j]**exp if i == j else 0)
|
|
|
|
if exp.is_Number and exp % 1 == 0:
|
|
if a.rows == 1:
|
|
return a._new([[a[0]**exp]])
|
|
if exp < 0:
|
|
exp = -exp
|
|
a = a.inv()
|
|
# When certain conditions are met,
|
|
# Jordan block algorithm is faster than
|
|
# computation by recursion.
|
|
if method == 'jordan':
|
|
try:
|
|
return jordan_pow(exp)
|
|
except MatrixError:
|
|
if method == 'jordan':
|
|
raise
|
|
|
|
elif method == 'cayley':
|
|
if not exp.is_Number or exp % 1 != 0:
|
|
raise ValueError("cayley method is only valid for integer powers")
|
|
return a._eval_pow_by_cayley(exp)
|
|
|
|
elif method == "mulsimp":
|
|
if not exp.is_Number or exp % 1 != 0:
|
|
raise ValueError("mulsimp method is only valid for integer powers")
|
|
return a._eval_pow_by_recursion_dotprodsimp(exp)
|
|
|
|
elif method == "multiply":
|
|
if not exp.is_Number or exp % 1 != 0:
|
|
raise ValueError("multiply method is only valid for integer powers")
|
|
return a._eval_pow_by_recursion(exp)
|
|
|
|
elif method is None and exp.is_Number and exp % 1 == 0:
|
|
# Decide heuristically which method to apply
|
|
if a.rows == 2 and exp > 100000:
|
|
return jordan_pow(exp)
|
|
elif _get_intermediate_simp_bool(True, None):
|
|
return a._eval_pow_by_recursion_dotprodsimp(exp)
|
|
elif exp > 10000:
|
|
return a._eval_pow_by_cayley(exp)
|
|
else:
|
|
return a._eval_pow_by_recursion(exp)
|
|
|
|
if jordan_pow:
|
|
try:
|
|
return jordan_pow(exp)
|
|
except NonInvertibleMatrixError:
|
|
# Raised by jordan_pow on zero determinant matrix unless exp is
|
|
# definitely known to be a non-negative integer.
|
|
# Here we raise if n is definitely not a non-negative integer
|
|
# but otherwise we can leave this as an unevaluated MatPow.
|
|
if exp.is_integer is False or exp.is_nonnegative is False:
|
|
raise
|
|
|
|
from sympy.matrices.expressions import MatPow
|
|
return MatPow(a, exp)
|
|
|
|
@call_highest_priority('__add__')
|
|
def __radd__(self, other):
|
|
return self + other
|
|
|
|
@call_highest_priority('__matmul__')
|
|
def __rmatmul__(self, other):
|
|
other = _matrixify(other)
|
|
if not getattr(other, 'is_Matrix', False) and not getattr(other, 'is_MatrixLike', False):
|
|
return NotImplemented
|
|
|
|
return self.__rmul__(other)
|
|
|
|
@call_highest_priority('__mul__')
|
|
def __rmul__(self, other):
|
|
return self.rmultiply(other)
|
|
|
|
def rmultiply(self, other, dotprodsimp=None):
|
|
"""Same as __rmul__() but with optional simplification.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
dotprodsimp : bool, optional
|
|
Specifies whether intermediate term algebraic simplification is used
|
|
during matrix multiplications to control expression blowup and thus
|
|
speed up calculation. Default is off.
|
|
"""
|
|
isimpbool = _get_intermediate_simp_bool(False, dotprodsimp)
|
|
other = _matrixify(other)
|
|
# matrix-like objects can have shapes. This is
|
|
# our first sanity check. Double check other is not explicitly not a Matrix.
|
|
if (hasattr(other, 'shape') and len(other.shape) == 2 and
|
|
(getattr(other, 'is_Matrix', True) or
|
|
getattr(other, 'is_MatrixLike', True))):
|
|
if self.shape[0] != other.shape[1]:
|
|
raise ShapeError("Matrix size mismatch.")
|
|
|
|
# honest sympy matrices defer to their class's routine
|
|
if getattr(other, 'is_Matrix', False):
|
|
m = self._eval_matrix_rmul(other)
|
|
if isimpbool:
|
|
return m._new(m.rows, m.cols, [_dotprodsimp(e) for e in m])
|
|
return m
|
|
# Matrix-like objects can be passed to CommonMatrix routines directly.
|
|
if getattr(other, 'is_MatrixLike', False):
|
|
return MatrixArithmetic._eval_matrix_rmul(self, other)
|
|
|
|
# if 'other' is not iterable then scalar multiplication.
|
|
if not isinstance(other, Iterable):
|
|
try:
|
|
return self._eval_scalar_rmul(other)
|
|
except TypeError:
|
|
pass
|
|
|
|
return NotImplemented
|
|
|
|
@call_highest_priority('__sub__')
|
|
def __rsub__(self, a):
|
|
return (-self) + a
|
|
|
|
@call_highest_priority('__rsub__')
|
|
def __sub__(self, a):
|
|
return self + (-a)
|
|
|
|
class MatrixCommon(MatrixArithmetic, MatrixOperations, MatrixProperties,
|
|
MatrixSpecial, MatrixShaping):
|
|
"""All common matrix operations including basic arithmetic, shaping,
|
|
and special matrices like `zeros`, and `eye`."""
|
|
_diff_wrt = True # type: bool
|
|
|
|
|
|
class _MinimalMatrix:
|
|
"""Class providing the minimum functionality
|
|
for a matrix-like object and implementing every method
|
|
required for a `MatrixRequired`. This class does not have everything
|
|
needed to become a full-fledged SymPy object, but it will satisfy the
|
|
requirements of anything inheriting from `MatrixRequired`. If you wish
|
|
to make a specialized matrix type, make sure to implement these
|
|
methods and properties with the exception of `__init__` and `__repr__`
|
|
which are included for convenience."""
|
|
|
|
is_MatrixLike = True
|
|
_sympify = staticmethod(sympify)
|
|
_class_priority = 3
|
|
zero = S.Zero
|
|
one = S.One
|
|
|
|
is_Matrix = True
|
|
is_MatrixExpr = False
|
|
|
|
@classmethod
|
|
def _new(cls, *args, **kwargs):
|
|
return cls(*args, **kwargs)
|
|
|
|
def __init__(self, rows, cols=None, mat=None, copy=False):
|
|
if isfunction(mat):
|
|
# if we passed in a function, use that to populate the indices
|
|
mat = list(mat(i, j) for i in range(rows) for j in range(cols))
|
|
if cols is None and mat is None:
|
|
mat = rows
|
|
rows, cols = getattr(mat, 'shape', (rows, cols))
|
|
try:
|
|
# if we passed in a list of lists, flatten it and set the size
|
|
if cols is None and mat is None:
|
|
mat = rows
|
|
cols = len(mat[0])
|
|
rows = len(mat)
|
|
mat = [x for l in mat for x in l]
|
|
except (IndexError, TypeError):
|
|
pass
|
|
self.mat = tuple(self._sympify(x) for x in mat)
|
|
self.rows, self.cols = rows, cols
|
|
if self.rows is None or self.cols is None:
|
|
raise NotImplementedError("Cannot initialize matrix with given parameters")
|
|
|
|
def __getitem__(self, key):
|
|
def _normalize_slices(row_slice, col_slice):
|
|
"""Ensure that row_slice and col_slice don't have
|
|
`None` in their arguments. Any integers are converted
|
|
to slices of length 1"""
|
|
if not isinstance(row_slice, slice):
|
|
row_slice = slice(row_slice, row_slice + 1, None)
|
|
row_slice = slice(*row_slice.indices(self.rows))
|
|
|
|
if not isinstance(col_slice, slice):
|
|
col_slice = slice(col_slice, col_slice + 1, None)
|
|
col_slice = slice(*col_slice.indices(self.cols))
|
|
|
|
return (row_slice, col_slice)
|
|
|
|
def _coord_to_index(i, j):
|
|
"""Return the index in _mat corresponding
|
|
to the (i,j) position in the matrix. """
|
|
return i * self.cols + j
|
|
|
|
if isinstance(key, tuple):
|
|
i, j = key
|
|
if isinstance(i, slice) or isinstance(j, slice):
|
|
# if the coordinates are not slices, make them so
|
|
# and expand the slices so they don't contain `None`
|
|
i, j = _normalize_slices(i, j)
|
|
|
|
rowsList, colsList = list(range(self.rows))[i], \
|
|
list(range(self.cols))[j]
|
|
indices = (i * self.cols + j for i in rowsList for j in
|
|
colsList)
|
|
return self._new(len(rowsList), len(colsList),
|
|
list(self.mat[i] for i in indices))
|
|
|
|
# if the key is a tuple of ints, change
|
|
# it to an array index
|
|
key = _coord_to_index(i, j)
|
|
return self.mat[key]
|
|
|
|
def __eq__(self, other):
|
|
try:
|
|
classof(self, other)
|
|
except TypeError:
|
|
return False
|
|
return (
|
|
self.shape == other.shape and list(self) == list(other))
|
|
|
|
def __len__(self):
|
|
return self.rows*self.cols
|
|
|
|
def __repr__(self):
|
|
return "_MinimalMatrix({}, {}, {})".format(self.rows, self.cols,
|
|
self.mat)
|
|
|
|
@property
|
|
def shape(self):
|
|
return (self.rows, self.cols)
|
|
|
|
|
|
class _CastableMatrix: # this is needed here ONLY FOR TESTS.
|
|
def as_mutable(self):
|
|
return self
|
|
|
|
def as_immutable(self):
|
|
return self
|
|
|
|
|
|
class _MatrixWrapper:
|
|
"""Wrapper class providing the minimum functionality for a matrix-like
|
|
object: .rows, .cols, .shape, indexability, and iterability. CommonMatrix
|
|
math operations should work on matrix-like objects. This one is intended for
|
|
matrix-like objects which use the same indexing format as SymPy with respect
|
|
to returning matrix elements instead of rows for non-tuple indexes.
|
|
"""
|
|
|
|
is_Matrix = False # needs to be here because of __getattr__
|
|
is_MatrixLike = True
|
|
|
|
def __init__(self, mat, shape):
|
|
self.mat = mat
|
|
self.shape = shape
|
|
self.rows, self.cols = shape
|
|
|
|
def __getitem__(self, key):
|
|
if isinstance(key, tuple):
|
|
return sympify(self.mat.__getitem__(key))
|
|
|
|
return sympify(self.mat.__getitem__((key // self.rows, key % self.cols)))
|
|
|
|
def __iter__(self): # supports numpy.matrix and numpy.array
|
|
mat = self.mat
|
|
cols = self.cols
|
|
|
|
return iter(sympify(mat[r, c]) for r in range(self.rows) for c in range(cols))
|
|
|
|
|
|
class MatrixKind(Kind):
|
|
"""
|
|
Kind for all matrices in SymPy.
|
|
|
|
Basic class for this kind is ``MatrixBase`` and ``MatrixExpr``,
|
|
but any expression representing the matrix can have this.
|
|
|
|
Parameters
|
|
==========
|
|
|
|
element_kind : Kind
|
|
Kind of the element. Default is :obj:NumberKind `<sympy.core.kind.NumberKind>`,
|
|
which means that the matrix contains only numbers.
|
|
|
|
Examples
|
|
========
|
|
|
|
Any instance of matrix class has ``MatrixKind``.
|
|
|
|
>>> from sympy import MatrixSymbol
|
|
>>> A = MatrixSymbol('A', 2,2)
|
|
>>> A.kind
|
|
MatrixKind(NumberKind)
|
|
|
|
Although expression representing a matrix may be not instance of
|
|
matrix class, it will have ``MatrixKind`` as well.
|
|
|
|
>>> from sympy import Integral
|
|
>>> from sympy.matrices.expressions import MatrixExpr
|
|
>>> from sympy.abc import x
|
|
>>> intM = Integral(A, x)
|
|
>>> isinstance(intM, MatrixExpr)
|
|
False
|
|
>>> intM.kind
|
|
MatrixKind(NumberKind)
|
|
|
|
Use ``isinstance()`` to check for ``MatrixKind` without specifying
|
|
the element kind. Use ``is`` with specifying the element kind.
|
|
|
|
>>> from sympy import Matrix
|
|
>>> from sympy.matrices import MatrixKind
|
|
>>> from sympy.core.kind import NumberKind
|
|
>>> M = Matrix([1, 2])
|
|
>>> isinstance(M.kind, MatrixKind)
|
|
True
|
|
>>> M.kind is MatrixKind(NumberKind)
|
|
True
|
|
|
|
See Also
|
|
========
|
|
|
|
shape : Function to return the shape of objects with ``MatrixKind``.
|
|
|
|
"""
|
|
def __new__(cls, element_kind=NumberKind):
|
|
obj = super().__new__(cls, element_kind)
|
|
obj.element_kind = element_kind
|
|
return obj
|
|
|
|
def __repr__(self):
|
|
return "MatrixKind(%s)" % self.element_kind
|
|
|
|
|
|
def _matrixify(mat):
|
|
"""If `mat` is a Matrix or is matrix-like,
|
|
return a Matrix or MatrixWrapper object. Otherwise
|
|
`mat` is passed through without modification."""
|
|
|
|
if getattr(mat, 'is_Matrix', False) or getattr(mat, 'is_MatrixLike', False):
|
|
return mat
|
|
|
|
if not(getattr(mat, 'is_Matrix', True) or getattr(mat, 'is_MatrixLike', True)):
|
|
return mat
|
|
|
|
shape = None
|
|
|
|
if hasattr(mat, 'shape'): # numpy, scipy.sparse
|
|
if len(mat.shape) == 2:
|
|
shape = mat.shape
|
|
elif hasattr(mat, 'rows') and hasattr(mat, 'cols'): # mpmath
|
|
shape = (mat.rows, mat.cols)
|
|
|
|
if shape:
|
|
return _MatrixWrapper(mat, shape)
|
|
|
|
return mat
|
|
|
|
|
|
def a2idx(j, n=None):
|
|
"""Return integer after making positive and validating against n."""
|
|
if type(j) is not int:
|
|
jindex = getattr(j, '__index__', None)
|
|
if jindex is not None:
|
|
j = jindex()
|
|
else:
|
|
raise IndexError("Invalid index a[%r]" % (j,))
|
|
if n is not None:
|
|
if j < 0:
|
|
j += n
|
|
if not (j >= 0 and j < n):
|
|
raise IndexError("Index out of range: a[%s]" % (j,))
|
|
return int(j)
|
|
|
|
|
|
def classof(A, B):
|
|
"""
|
|
Get the type of the result when combining matrices of different types.
|
|
|
|
Currently the strategy is that immutability is contagious.
|
|
|
|
Examples
|
|
========
|
|
|
|
>>> from sympy import Matrix, ImmutableMatrix
|
|
>>> from sympy.matrices.common import classof
|
|
>>> M = Matrix([[1, 2], [3, 4]]) # a Mutable Matrix
|
|
>>> IM = ImmutableMatrix([[1, 2], [3, 4]])
|
|
>>> classof(M, IM)
|
|
<class 'sympy.matrices.immutable.ImmutableDenseMatrix'>
|
|
"""
|
|
priority_A = getattr(A, '_class_priority', None)
|
|
priority_B = getattr(B, '_class_priority', None)
|
|
if None not in (priority_A, priority_B):
|
|
if A._class_priority > B._class_priority:
|
|
return A.__class__
|
|
else:
|
|
return B.__class__
|
|
|
|
try:
|
|
import numpy
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
if isinstance(A, numpy.ndarray):
|
|
return B.__class__
|
|
if isinstance(B, numpy.ndarray):
|
|
return A.__class__
|
|
|
|
raise TypeError("Incompatible classes %s, %s" % (A.__class__, B.__class__))
|