"""
Single-frequency amplitude and phase detector.
"""
import numbers
import logging
import numpy as np
from finesse.detectors.compute.amplitude import ADWorkspace
from finesse.detectors.general import MaskedDetector
from finesse.parameter import float_parameter
LOGGER = logging.getLogger(__name__)
[docs]@float_parameter("f", "Frequency", units="Hz")
class AmplitudeDetector(MaskedDetector):
"""Represents an amplitude detector which calculates the amplitude and phase of light fields
at one frequency.
Parameters
----------
name : str
Name of newly created detector.
node : :class:`.Node`
Node to read output from.
f : float
Frequency of light to detect (in Hz).
n : int, optional; default: None
Tangential mode index to probe. Defaults to None such that
all fields of the given frequency are summed.
m : int, optional; default: None
Sagittal mode index to probe. Defaults to None such that
all fields of the given frequency are summed.
"""
def __init__(self, name, node, f, n=None, m=None):
MaskedDetector.__init__(
self, name, node, dtype=np.complex128, label="Amplitude"
)
self.f = f
if (n is None and m is not None) or (m is None and n is not None):
raise ValueError(
f"Error in amplitude detector {self.name}:\n"
f" Expected both OR neither of n and m to be specified but "
f"got n = {n} and m = {m}"
)
self.__check_mode_number(n, "n")
self.__check_mode_number(m, "m")
self.__n = n
self.__m = m
def __check_mode_number(self, k, mode_str):
if k is not None:
if (
not isinstance(k, numbers.Number)
or k < 0
or (
hasattr(k, "is_integer")
and not k.is_integer()
and not isinstance(k, numbers.Integral)
)
):
raise ValueError(
f"Error in amplitude detector {self.name}:\n"
f" Expected argument {mode_str} to be None or a positive integer "
f"but got {mode_str} = {k}"
)
@property
def n(self):
"""The tangential mode index to probe.
:getter: Returns the tangential mode index being probed (read-only).
"""
return self.__n
@property
def m(self):
"""The sagittal mode index to probe.
:getter: Returns the sagittal mode index being probed (read-only).
"""
return self.__m
def _get_workspace(self, sim):
return ADWorkspace(self, sim)