# -*- coding: utf-8 -*-
"""The LinearDimension sub type class."""
from __future__ import division
from __future__ import print_function
import json
from copy import deepcopy
import numpy as np
from astropy.units import Quantity
from csdmpy.dimensions.base import _copy_core_metadata
from csdmpy.dimensions.quantitative import BaseQuantitativeDimension
from csdmpy.dimensions.quantitative import ReciprocalDimension
from csdmpy.units import frequency_ratio
from csdmpy.units import ScalarQuantity
from csdmpy.utils import _axis_label
from csdmpy.utils import check_and_assign_bool
from csdmpy.utils import check_scalar_object
from csdmpy.utils import validate
__author__ = "Deepansh J. Srivastava"
__email__ = "srivastava.89@osu.edu"
__all__ = ["LinearDimension"]
# =========================================================================== #
# LinearDimension Class #
# =========================================================================== #
[docs]class LinearDimension(BaseQuantitativeDimension):
r"""
LinearDimension class.
Generates an object representing a physical dimension whose coordinates are
uniformly sampled along a grid dimension. See :ref:`linearDimension_uml` for
details.
"""
__slots__ = ("_count", "_increment", "_complex_fft", "reciprocal", "_coordinates")
_type = "linear"
def __init__(self, count, increment, complex_fft=False, **kwargs):
r"""Instantiate a DimensionWithLinearSpacing class instance."""
self._count = count
self._increment = ScalarQuantity(increment).quantity
self._complex_fft = check_and_assign_bool(complex_fft)
_unit = self._increment.unit
if "reciprocal" not in kwargs.keys():
kwargs["reciprocal"] = {
"increment": None,
"coordinates_offset": None,
"origin_offset": None,
"period": None,
"quantity_name": None,
"label": "",
"description": "",
"application": {},
}
super().__init__(unit=_unit, **kwargs)
# create a reciprocal dimension
_reciprocal_unit = self._unit ** -1
self.reciprocal = ReciprocalDimension(
unit=_reciprocal_unit, **kwargs["reciprocal"]
)
self._get_coordinates()
def __repr__(self):
properties = ", ".join(
[f"{k}={v}" for k, v in self.to_dict().items() if k != "type"]
)
return f"LinearDimension({properties})"
def __str__(self):
return f"LinearDimension({self.coordinates.__str__()})"
def __eq__(self, other):
"""Overrides the default implementation"""
if hasattr(other, "subtype"):
other = other.subtype
if isinstance(other, LinearDimension):
check = [
self._count == other._count,
self._increment == other._increment,
self._complex_fft == other._complex_fft,
self.reciprocal == other.reciprocal,
# super class
self._coordinates_offset == other._coordinates_offset,
self._origin_offset == other._origin_offset,
self._quantity_name == other._quantity_name,
self._period == other._period,
self._label == other._label,
self._description == other._description,
self._application == other._application,
self._unit == other._unit,
self._equivalencies == other._equivalencies,
]
if np.all(check):
return True
return False
def __mul__(self, other):
"""Multiply the LinearDimension object by a scalar."""
return _update_linear_dimension_object_by_scalar(self.copy(), other, "mul")
def __imul__(self, other):
"""Multiply the LinearDimension object by a scalar, in-place."""
return _update_linear_dimension_object_by_scalar(self, other, "mul")
def __truediv__(self, other):
"""Divide the LinearDimension object by a scalar."""
return _update_linear_dimension_object_by_scalar(self.copy(), other, "truediv")
def __itruediv__(self, other):
"""Divide the LinearDimension object by a scalar, in-place."""
return _update_linear_dimension_object_by_scalar(self, other, "truediv")
def _swap(self):
self._description, self.reciprocal._description = (
self.reciprocal._description,
self._description,
)
self._application, self.reciprocal._application = (
self.reciprocal._application,
self._application,
)
self._coordinates_offset, self.reciprocal._coordinates_offset = (
self.reciprocal._coordinates_offset,
self._coordinates_offset,
)
self._origin_offset, self.reciprocal._origin_offset = (
self.reciprocal._origin_offset,
self._origin_offset,
)
self._period, self.reciprocal._period = (self.reciprocal._period, self._period)
self._quantity_name, self.reciprocal._quantity_name = (
self.reciprocal._quantity_name,
self._quantity_name,
)
self._label, self.reciprocal._label = (self.reciprocal._label, self._label)
self._unit, self.reciprocal._unit = self.reciprocal._unit, self._unit
self._equivalent_unit, self.reciprocal._equivalent_unit = (
self.reciprocal._equivalent_unit,
self._equivalent_unit,
)
def _get_coordinates(self):
_unit = self._unit
_count = self._count
_increment = self._increment.to(_unit)
_index = np.arange(_count, dtype=np.float64)
if self._complex_fft:
_index -= int(_count / 2)
self._coordinates = _index * _increment
# ----------------------------------------------------------------------- #
# Attributes #
# ----------------------------------------------------------------------- #
@property
def type(self):
"""Return the type of the dimension."""
return self.__class__._type
@property
def count(self):
r"""Total number of points along the linear dimension."""
return self._count
@count.setter
def count(self, value):
value = validate(value, "count", int)
self._count = value
self._get_coordinates()
return
@property
def increment(self):
r"""Increment along the linear dimension."""
return self._increment
@increment.setter
def increment(self, value):
allowed_types = (Quantity, str, ScalarQuantity)
value = validate(value, "increment", allowed_types)
self._increment = ScalarQuantity(value, self._unit).quantity
self._get_coordinates()
@property
def complex_fft(self):
"""If True, orders the coordinates according to FFT output order."""
return self._complex_fft
@complex_fft.setter
def complex_fft(self, value):
self._complex_fft = validate(value, "complex_fft", bool)
self._get_coordinates()
@property
def coordinates(self):
"""Return the coordinates along the dimensions."""
n = self._count
coordinates = self._coordinates[:n] + self.coordinates_offset
equivalent_fn = self._equivalencies
equivalent_unit = self._equivalent_unit
if equivalent_fn is None or equivalent_unit is None:
return coordinates.to(self._unit)
if equivalent_fn == "nmr_frequency_ratio":
denominator = self.origin_offset - self.coordinates_offset
if denominator.value == 0:
raise ZeroDivisionError("Cannot convert the coordinates to ppm.")
return coordinates.to(equivalent_unit, frequency_ratio(denominator))
return coordinates.to(equivalent_unit, equivalent_fn)
@coordinates.setter
def coordinates(self, value):
raise AttributeError(
"The attribute cannot be modifed for Dimension objects with `linear` "
"type. Use the `count`, `increment` or `coordinates_offset` attributes"
" to update the coordinate along the linear dimension."
)
@property
def absolute_coordinates(self):
"""Return the absolute coordinates along the dimensions."""
return (self.coordinates + self.origin_offset).to(self._unit)
@property
def axis_label(self):
"""Return a formatted string for displaying label along the dimension axis."""
if self.label.strip() == "":
label = self.quantity_name
else:
label = self.label
unit = (
self._equivalent_unit if self._equivalent_unit is not None else self._unit
)
return _axis_label(label, unit)
@property
def data_structure(self):
"""Json serialized string describing the LinearDimension class instance."""
return json.dumps(self.to_dict(), ensure_ascii=False, sort_keys=False, indent=2)
# ----------------------------------------------------------------------- #
# Methods #
# ----------------------------------------------------------------------- #
def _copy_metadata(self, obj, copy=False):
"""Copy LinearDimension metadata."""
if hasattr(obj, "subtype"):
obj = obj.subtype
if isinstance(obj, LinearDimension):
_copy_core_metadata(self, obj, "linear")
[docs] def to_dict(self):
"""Return the LinearDimension as a python dictionary."""
obj = {}
obj["type"] = self.__class__._type
if self._description.strip() != "":
obj["description"] = self._description.strip()
obj["count"] = self._count
obj["increment"] = str(ScalarQuantity(self.increment))
obj.update(self._to_dict())
if self.complex_fft:
obj["complex_fft"] = True
# reciprocal dictionary
reciprocal_obj = {}
if self.reciprocal._description.strip() != "":
reciprocal_obj["description"] = self.reciprocal._description
reciprocal_obj.update(self.reciprocal._to_dict())
if reciprocal_obj == {}:
del reciprocal_obj
else:
obj["reciprocal"] = reciprocal_obj
return obj
[docs] def copy(self):
"""Return a copy of the object."""
return deepcopy(self)
[docs] def reciprocal_coordinates(self):
"""Return reciprocal coordinates assuming Nyquist-shannan theorem."""
count = self._count
increment = 1.0 / (count * self._increment)
coordinates_offset = self.reciprocal._coordinates_offset
coordinates = np.arange(count) * increment + coordinates_offset
if self.complex_fft:
return coordinates
return coordinates - int(count / 2) * increment
[docs] def reciprocal_increment(self):
"""Return reciprocal increment assuming Nyquist-shannan theorem."""
return 1.0 / (self._count * self._increment)
def _update_linear_dimension_object_by_scalar(object_, other, type_="mul"):
"""Update object by multiplying by a scalar."""
other = check_scalar_object(other)
if type_ == "mul":
object_._increment *= other
object_._coordinates *= other
object_._coordinates_offset *= other
object_._origin_offset *= other
object_._period *= other
if type_ == "truediv":
object_._increment /= other
object_._coordinates /= other
object_._coordinates_offset /= other
object_._origin_offset /= other
object_._period /= other
object_._unit = object_._increment._unit
object_._quantity_name = object_._unit.physical_type
object_._equivalencies = None
_reciprocal_unit = object_._unit ** -1
object_.reciprocal = ReciprocalDimension(unit=_reciprocal_unit)
return object_
