import numpy as np
from pylops import LinearOperator
from pylops.utils.backend import get_array_module
[docs]class Real(LinearOperator):
r"""Real operator.
Return the real component of the input. The adjoint returns a complex
number with the same real component as the input and zero imaginary
component.
Parameters
----------
dims : :obj:`int` or :obj:`tuple`
Number of samples for each dimension
dtype : :obj:`str`, optional
Type of elements in input array.
Attributes
----------
shape : :obj:`tuple`
Operator shape
explicit : :obj:`bool`
Operator contains a matrix that can be solved explicitly (``True``) or
not (``False``)
Notes
-----
In forward mode:
.. math::
y_{i} = \Re\{x_{i}\} \quad \forall i=0,\ldots,N-1
In adjoint mode:
.. math::
x_{i} = \Re\{y_{i}\} + 0i \quad \forall i=0,\ldots,N-1
"""
def __init__(self, dims, dtype="complex128"):
self.shape = (np.prod(np.array(dims)), np.prod(np.array(dims)))
self.dtype = np.dtype(dtype)
self.rdtype = np.real(np.ones(1, self.dtype)).dtype
self.explicit = False
self.clinear = False
def _matvec(self, x):
ncp = get_array_module(x)
return ncp.real(x).astype(self.rdtype)
def _rmatvec(self, x):
ncp = get_array_module(x)
return (ncp.real(x) + 0j).astype(self.dtype)