Source code for pymor.vectorarrays.list

# This file is part of the pyMOR project (http://www.pymor.org).
# Copyright 2013-2020 pyMOR developers and contributors. All rights reserved.
# License: BSD 2-Clause License (http://opensource.org/licenses/BSD-2-Clause)

from numbers import Number

import numpy as np

from pymor.core.base import BasicObject, abstractmethod, abstractclassmethod, classinstancemethod
from pymor.tools.random import get_random_state
from pymor.vectorarrays.interface import VectorArray, VectorSpace, _create_random_values


[docs]class Vector(BasicObject): """Interface for vectors used in conjunction with |ListVectorArray|. This interface must be satisfied by the individual entries of the vector `list` managed by |ListVectorArray|. All interface methods have a direct counterpart in the |VectorArray| interface. """ @abstractmethod def copy(self, deep=False): pass @abstractmethod def scal(self, alpha): pass @abstractmethod def axpy(self, alpha, x): pass @abstractmethod def dot(self, other): pass @abstractmethod def l1_norm(self): pass @abstractmethod def l2_norm(self): pass @abstractmethod def l2_norm2(self): pass def sup_norm(self): _, max_val = self.amax() return max_val @abstractmethod def dofs(self, dof_indices): pass @abstractmethod def amax(self): pass def __add__(self, other): result = self.copy() result.axpy(1, other) return result def __iadd__(self, other): self.axpy(1, other) return self __radd__ = __add__ def __sub__(self, other): result = self.copy() result.axpy(-1, other) return result def __isub__(self, other): self.axpy(-1, other) return self def __mul__(self, other): result = self.copy() result.scal(other) return result def __imul__(self, other): self.scal(other) return self def __neg__(self): result = self.copy() result.scal(-1) return result @property def real(self): return self.copy() @property def imag(self): return None def conj(self): return self.copy()
[docs]class CopyOnWriteVector(Vector): @abstractclassmethod def from_instance(cls, instance): pass @abstractmethod def _copy_data(self): pass @abstractmethod def _scal(self, alpha): pass @abstractmethod def _axpy(self, alpha, x): pass def copy(self, deep=False): c = self.from_instance(self) if deep: c._copy_data() else: try: self._refcount[0] += 1 except AttributeError: self._refcount = [2] c._refcount = self._refcount return c def scal(self, alpha): self._copy_data_if_needed() self._scal(alpha) def axpy(self, alpha, x): self._copy_data_if_needed() self._axpy(alpha, x) def __del__(self): try: self._refcount[0] -= 1 except AttributeError: pass def _copy_data_if_needed(self): try: if self._refcount[0] > 1: self._refcount[0] -= 1 self._copy_data() self._refcount = [1] except AttributeError: self._refcount = [1]
[docs]class ComplexifiedVector(Vector): def __init__(self, real_part, imag_part): self.real_part, self.imag_part = real_part, imag_part def copy(self, deep=False): real_part = self.real_part.copy(deep=deep) imag_part = self.imag_part.copy(deep=deep) if self.imag_part is not None else None return type(self)(real_part, imag_part) def scal(self, alpha): if self.imag_part is None: self.real_part.scal(alpha.real) if alpha.imag != 0: self.imag_part = self.real_part * alpha.imag else: if alpha.imag == 0: self.real_part.scal(alpha.real) self.imag_part.scal(alpha.real) else: old_real_part = self.real_part.copy() self.real_part.scal(alpha.real) self.real_part.axpy(-alpha.imag, self.imag_part) self.imag_part.scal(alpha.real) self.imag_part.axpy(alpha.imag, old_real_part) def axpy(self, alpha, x): if x is self: self.scal(1. + alpha) return # real part self.real_part.axpy(alpha.real, x.real_part) if x.imag_part is not None: self.real_part.axpy(-alpha.imag, x.imag_part) # imaginary part if alpha.imag != 0: if self.imag_part is None: self.imag_part = x.real_part * alpha.imag else: self.imag_part.axpy(alpha.imag, x.real_part) if x.imag_part is not None: if self.imag_part is None: self.imag_part = x.imag_part * alpha.real else: self.imag_part.axpy(alpha.real, x.imag_part) def dot(self, other): result = self.real_part.dot(other.real_part) if self.imag_part is not None: result += self.imag_part.dot(other.real_part) * (-1j) if other.imag_part is not None: result += self.real_part.dot(other.imag_part) * 1j if self.imag_part is not None and other.imag_part is not None: result += self.imag_part.dot(other.imag_part) return result def l1_norm(self): if self.imag_part is not None: raise NotImplementedError return self.real_part.l1_norm() def l2_norm(self): result = self.real_part.l2_norm() if self.imag_part is not None: result = np.linalg.norm([result, self.imag_part.l2_norm()]) return result def l2_norm2(self): result = self.real_part.l2_norm2() if self.imag_part is not None: result += self.imag_part.l2_norm2() return result def sup_norm(self): if self.imag_part is not None: # we cannot compute the sup_norm from the sup_norms of real_part and imag_part return self.amax()[1] return self.real_part.sup_norm() def dofs(self, dof_indices): values = self.real_part.dofs(dof_indices) if self.imag_part is not None: imag_values = self.imag_part.dofs(dof_indices) return values + imag_values * 1j else: return values def amax(self): if self.imag_part is not None: raise NotImplementedError return self.real_part.amax() def to_numpy(self, ensure_copy=False): if self.imag_part is not None: return self.real_part.to_numpy(ensure_copy=False) + self.imag_part.to_numpy(ensure_copy=False) * 1j else: return self.real_part.to_numpy(ensure_copy=ensure_copy) @property def real(self): return type(self)(self.real_part.copy(), None) @property def imag(self): return type(self)(self.imag_part.copy(), None) if self.imag_part is not None else None def conj(self): return type(self)(self.real_part.copy(), -self.imag_part if self.imag_part is not None else None)
[docs]class NumpyVector(CopyOnWriteVector): """Vector stored in a NumPy 1D-array.""" def __init__(self, array): self._array = array @classmethod def from_instance(cls, instance): return cls(instance._array) def to_numpy(self, ensure_copy=False): if ensure_copy: return self._array.copy() else: self._copy_data_if_needed() return self._array @property def dim(self): return len(self._array) def _copy_data(self): self._array = self._array.copy() def _scal(self, alpha): try: self._array *= alpha except TypeError: # e.g. when scaling real array by complex alpha self._array = self._array * alpha def _axpy(self, alpha, x): assert self.dim == x.dim if alpha == 0: return if alpha == 1: try: self._array += x._array except TypeError: self._array = self._array + x._array elif alpha == -1: try: self._array -= x._array except TypeError: self._array = self._array - x._array else: try: self._array += x._array * alpha except TypeError: self._array = self._array + x._array * alpha def dot(self, other): assert self.dim == other.dim return np.sum(self._array.conj() * other._array) def l1_norm(self): return np.sum(np.abs(self._array)) def l2_norm(self): return np.linalg.norm(self._array) def l2_norm2(self): return np.sum((self._array * self._array.conj()).real) def dofs(self, dof_indices): return self._array[dof_indices] def amax(self): A = np.abs(self._array) max_ind = np.argmax(A) max_val = A[max_ind] return max_ind, np.abs(max_val) @property def real(self): return self.__class__(self._array.real.copy()) @property def imag(self): return self.__class__(self._array.imag.copy()) def conj(self): return self.__class__(self._array.conj())
[docs]class ListVectorArray(VectorArray): """|VectorArray| implemented as a Python list of vectors. This |VectorArray| implementation is the first choice when creating pyMOR wrappers for external solvers which are based on single vector objects. In order to do so, a wrapping subclass of :class:`Vector` has to be provided on which the implementation of |ListVectorArray| will operate. The associated |VectorSpace| is a subclass of :class:`ListVectorSpace`. For an example, see :class:`NumpyVector`, :class:`NumpyListVectorSpace` or :class:`~pymor.bindings.fenics.FenicsVector`, :class:`~pymor.bindings.fenics.FenicsVectorSpace`. """ _NONE = () def __init__(self, vectors, space): self._list = vectors self.space = space
[docs] def to_numpy(self, ensure_copy=False): if len(self._list) > 0: return np.array([v.to_numpy() for v in self._list]) else: return np.empty((0, self.dim))
@property def _data(self): """Return list of NumPy Array views on vector data for hacking / interactive use.""" return ListVectorArrayNumpyView(self)
[docs] def __len__(self): return len(self._list)
[docs] def __getitem__(self, ind): return ListVectorArrayView(self, ind)
[docs] def __delitem__(self, ind): assert self.check_ind(ind) if hasattr(ind, '__len__'): thelist = self._list l = len(thelist) remaining = sorted(set(range(l)) - {i if 0 <= i else l+i for i in ind}) self._list = [thelist[i] for i in remaining] else: del self._list[ind]
[docs] def append(self, other, remove_from_other=False): assert other.space == self.space assert not remove_from_other or (other is not self and getattr(other, 'base', None) is not self) if not remove_from_other: self._list.extend([v.copy() for v in other._list]) else: self._list.extend(other._list) if other.is_view: del other.base[other.ind] else: del other[:]
[docs] def copy(self, deep=False): return ListVectorArray([v.copy(deep=deep) for v in self._list], self.space)
[docs] def scal(self, alpha): assert isinstance(alpha, Number) \ or isinstance(alpha, np.ndarray) and alpha.shape == (len(self),) if type(alpha) is np.ndarray: for a, v in zip(alpha, self._list): v.scal(a) else: for v in self._list: v.scal(alpha)
[docs] def axpy(self, alpha, x): assert self.space == x.space len_x = len(x) assert len(self) == len_x or len_x == 1 assert isinstance(alpha, Number) \ or isinstance(alpha, np.ndarray) and alpha.shape == (len(self),) if np.all(alpha == 0): return if self is x or x.is_view and self is x.base: x = x.copy() if len(x) == 1: xx = x._list[0] if type(alpha) is np.ndarray: for a, y in zip(alpha, self._list): y.axpy(a, xx) else: for y in self._list: y.axpy(alpha, xx) else: if type(alpha) is np.ndarray: for a, xx, y in zip(alpha, x._list, self._list): y.axpy(a, xx) else: for xx, y in zip(x._list, self._list): y.axpy(alpha, xx)
[docs] def dot(self, other): assert self.space == other.space return np.array([[a.dot(b) for b in other._list] for a in self._list]).reshape((len(self), len(other)))
[docs] def pairwise_dot(self, other): assert self.space == other.space assert len(self._list) == len(other) return np.array([a.dot(b) for a, b in zip(self._list, other._list)])
[docs] def gramian(self, product=None): if product is not None: return super().gramian(product) l = len(self._list) R = [[0.] * l for _ in range(l)] for i in range(l): for j in range(i, l): R[i][j] = self._list[i].dot(self._list[j]) if i == j: R[i][j] = R[i][j].real else: R[j][i] = R[i][j].conjugate() R = np.array(R) return R
[docs] def lincomb(self, coefficients): assert 1 <= coefficients.ndim <= 2 if coefficients.ndim == 1: coefficients = coefficients[np.newaxis, :] assert coefficients.shape[1] == len(self) RL = [] for coeffs in coefficients: R = self.space.zero_vector() for v, c in zip(self._list, coeffs): R.axpy(c, v) RL.append(R) return ListVectorArray(RL, self.space)
[docs] def l1_norm(self): return np.array([v.l1_norm() for v in self._list])
[docs] def l2_norm(self): return np.array([v.l2_norm() for v in self._list])
[docs] def l2_norm2(self): return np.array([v.l2_norm2() for v in self._list])
[docs] def sup_norm(self): if self.dim == 0: return np.zeros(len(self)) else: return np.array([v.sup_norm() for v in self._list])
[docs] def dofs(self, dof_indices): assert isinstance(dof_indices, list) and (len(dof_indices) == 0 or min(dof_indices) >= 0) \ or (isinstance(dof_indices, np.ndarray) and dof_indices.ndim == 1 and (len(dof_indices) == 0 or np.min(dof_indices) >= 0)) assert len(self) > 0 or len(dof_indices) == 0 or max(dof_indices) < self.dim return np.array([v.dofs(dof_indices) for v in self._list]).reshape((len(self), len(dof_indices)))
[docs] def amax(self): assert self.dim > 0 MI = np.empty(len(self._list), dtype=np.int) MV = np.empty(len(self._list)) for k, v in enumerate(self._list): MI[k], MV[k] = v.amax() return MI, MV
@property def real(self): return ListVectorArray([v.real for v in self._list], self.space) @property def imag(self): # note that Vector.imag is allowed to return None in case # of a real vector, so we have to check for that. # returning None is allowed as ComplexifiedVector does not know # how to create a new zero vector. return ListVectorArray([v.imag or self.space.zero_vector() for v in self._list], self.space)
[docs] def conj(self): return self.__class__([v.conj() for v in self._list], self.space)
[docs] def __str__(self): return f'ListVectorArray of {len(self._list)} of space {self.space}'
[docs]class ListVectorSpace(VectorSpace): """|VectorSpace| of |ListVectorArrays|.""" dim = None @abstractmethod def zero_vector(self): pass def ones_vector(self): return self.full_vector(1.) def full_vector(self, value): return self.vector_from_numpy(np.full(self.dim, value)) def random_vector(self, distribution, random_state, **kwargs): values = _create_random_values(self.dim, distribution, random_state, **kwargs) return self.vector_from_numpy(values) @abstractmethod def make_vector(self, obj): pass def vector_from_numpy(self, data, ensure_copy=False): raise NotImplementedError @classmethod def space_from_vector_obj(cls, vec, id): raise NotImplementedError @classmethod def space_from_dim(cls, dim, id): raise NotImplementedError
[docs] def zeros(self, count=1, reserve=0): assert count >= 0 and reserve >= 0 return ListVectorArray([self.zero_vector() for _ in range(count)], self)
[docs] def ones(self, count=1, reserve=0): assert count >= 0 and reserve >= 0 return ListVectorArray([self.ones_vector() for _ in range(count)], self)
[docs] def full(self, value, count=1, reserve=0): assert count >= 0 and reserve >= 0 return ListVectorArray([self.full_vector(value) for _ in range(count)], self)
[docs] def random(self, count=1, distribution='uniform', random_state=None, seed=None, reserve=0, **kwargs): assert count >= 0 and reserve >= 0 assert random_state is None or seed is None random_state = get_random_state(random_state, seed) return ListVectorArray([self.random_vector(distribution=distribution, random_state=random_state, **kwargs) for _ in range(count)], self)
@classinstancemethod def make_array(cls, obj, id=None): if len(obj) == 0: raise NotImplementedError return cls.space_from_vector_obj(obj[0], id=id).make_array(obj) @make_array.instancemethod def make_array(self, obj): return ListVectorArray([v if isinstance(v, Vector) else self.make_vector(v) for v in obj], self) @classinstancemethod def from_numpy(cls, data, id=None, ensure_copy=False): return cls.space_from_dim(data.shape[1], id=id).from_numpy(data, ensure_copy=ensure_copy) @from_numpy.instancemethod def from_numpy(self, data, ensure_copy=False): return ListVectorArray([self.vector_from_numpy(v, ensure_copy=ensure_copy) for v in data], self)
[docs]class ComplexifiedListVectorSpace(ListVectorSpace): complexified_vector_type = ComplexifiedVector @abstractmethod def real_zero_vector(self): pass def zero_vector(self): return self.complexified_vector_type(self.real_zero_vector(), None) def real_full_vector(self, value): return self.real_vector_from_numpy(np.full(self.dim, value)) def full_vector(self, value): return self.complexified_vector_type(self.real_full_vector(value), None) def real_random_vector(self, distribution, random_state, **kwargs): values = _create_random_values(self.dim, distribution, random_state, **kwargs) return self.real_vector_from_numpy(values) def random_vector(self, distribution, random_state, **kwargs): return self.complexified_vector_type(self.real_random_vector(distribution, random_state, **kwargs), None) @abstractmethod def real_make_vector(self, obj): pass def make_vector(self, obj): return self.complexified_vector_type(self.real_make_vector(obj), None) def real_vector_from_numpy(self, data, ensure_copy=False): raise NotImplementedError def vector_from_numpy(self, data, ensure_copy=False): if np.iscomplexobj(data): real_part = self.real_vector_from_numpy(data.real) imag_part = self.real_vector_from_numpy(data.imag) else: real_part = self.real_vector_from_numpy(data, ensure_copy=ensure_copy) imag_part = None return self.complexified_vector_type(real_part, imag_part)
[docs]class NumpyListVectorSpace(ListVectorSpace): def __init__(self, dim, id=None): self.dim = dim self.id = id
[docs] def __eq__(self, other): return type(other) is NumpyListVectorSpace and self.dim == other.dim and self.id == other.id
@classmethod def space_from_vector_obj(cls, vec, id): return cls(len(vec), id) @classmethod def space_from_dim(cls, dim, id): return cls(dim, id) def zero_vector(self): return NumpyVector(np.zeros(self.dim)) def ones_vector(self): return NumpyVector(np.ones(self.dim)) def full_vector(self, value): return NumpyVector(np.full(self.dim, value)) def make_vector(self, obj): obj = np.asarray(obj) assert obj.ndim == 1 and len(obj) == self.dim return NumpyVector(obj) def vector_from_numpy(self, data, ensure_copy=False): return self.make_vector(data.copy() if ensure_copy else data)
[docs]class ListVectorArrayView(ListVectorArray): is_view = True def __init__(self, base, ind): self.base = base assert base.check_ind(ind) self.ind = base.normalize_ind(ind) if type(ind) is slice: self._list = base._list[ind] elif hasattr(ind, '__len__'): _list = base._list self._list = [_list[i] for i in ind] else: self._list = [base._list[ind]] @property def space(self): return self.base.space
[docs] def __getitem__(self, ind): return self.base[self.base.sub_index(self.ind, ind)]
[docs] def __delitem__(self, ind): raise TypeError('Cannot remove from ListVectorArrayView')
[docs] def append(self, other, remove_from_other=False): raise TypeError('Cannot append to ListVectorArrayView')
[docs] def scal(self, alpha): assert self.base.check_ind_unique(self.ind) super().scal(alpha)
[docs] def axpy(self, alpha, x): assert self.base.check_ind_unique(self.ind) if x is self.base or x.is_view and x.base is self.base: x = x.copy() super().axpy(alpha, x)
[docs] def __str__(self): return f'ListVectorArrayView of {len(self._list)} {str(self.vector_type)}s of dimension {self.dim}'
[docs]class ListVectorArrayNumpyView: def __init__(self, array): self.array = array def __len__(self): return len(self.array) def __getitem__(self, i): return self.array._list[i].to_numpy()
[docs] def __repr__(self): return '[' + ',\n '.join(repr(v) for v in self) + ']'