Source code for PySpice.Unit.Unit

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#
# PySpice - A Spice Package for Python
# Copyright (C) 2014 Fabrice Salvaire
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
####################################################################################################

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"""This module implements units.

A shortcut is defined for each unit prefix, e.g. :class:`pico`, :class:`nano`, :class:`micro`,
:class:`milli`, :class:`kilo`, :class:`mega`, :class:`tera`.

"""

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import logging

import collections.abc as collections
import math
# import numbers

import numpy as np

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from PySpice.Tools.EnumFactory import EnumFactory

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_module_logger = logging.getLogger(__name__)

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[docs]class UnitPrefixMetaclass(type): """Metaclass to register unit prefixes""" __prefixes__ = {} # singletons ############################################## def __new__(meta, class_name, base_classes, attributes): cls = type.__new__(meta, class_name, base_classes, attributes) if class_name != 'UnitPrefix': meta.register_prefix(cls) return cls ##############################################
[docs] @classmethod def register_prefix(meta, cls): power = cls.__power__ if power is None: raise ValueError('Power is None for {}'.format(cls.__name__)) meta.__prefixes__[power] = cls()
##############################################
[docs] @classmethod def prefix_iter(cls): return cls.__prefixes__.values()
##############################################
[docs] @classmethod def get(cls, power): return cls.__prefixes__[power]
####################################################################################################
[docs]class UnitPrefix(metaclass=UnitPrefixMetaclass): """This class implements a unit prefix like kilo""" __power__ = None __prefix__ = '' ############################################## def __repr__(self): return '{}({}, {})'.format(self.__class__.__name__, self.__power__, self.__prefix__) ############################################## def __int__(self): return self.__power__ ############################################## def __str__(self): return self.__prefix__ ############################################## @property def power(self): return self.__power__ @property def prefix(self): return self.__prefix__ @property def is_unit(self): return self.__power__ == 0 @property def scale(self): return 10**self.__power__ ############################################## @property def spice_prefix(self): if hasattr(self, '__spice_prefix__'): return self.__spice_prefix__ else: return self.__prefix__ ############################################## @property def is_defined_in_spice(self): return self.spice_prefix is not None ############################################## def __eq__(self, other): return self.__power__ == other.__power__ ############################################## def __ne__(self, other): return self.__power__ != other.__power__ ############################################## def __lt__(self, other): return self.__power__ < other.__power__ ############################################## def __gt__(self, other): return self.__power__ > other.__power__ ##############################################
[docs] def str(self, spice=False): if spice: return self.spice_prefix else: return self.__prefix__
####################################################################################################
[docs]class ZeroPower(UnitPrefix): __power__ = 0 __prefix__ = '' __spice_prefix__ = ''
_zero_power = UnitPrefixMetaclass.get(0) ####################################################################################################
[docs]class SiDerivedUnit: """This class implements a unit defined as powers of SI base units. """ # SI base units __base_units__ = ( 'm', 'kg', 's', 'A', 'K', 'mol', 'cd', ) ############################################## def __init__(self, string=None, powers=None): if powers is not None: self._powers = self.new_powers() self._powers.update(powers) elif string is not None: self._powers = self.parse_si(string) else: self._powers = self.new_powers() self._hash = self.to_hash(self._powers) self._string = self.to_string(self._powers) ############################################## @property def powers(self): return self._powers @property def hash(self): return self._hash @property def string(self): return self._string def __str__(self): return self._string def __repr__(self): return '{}({})'.format(self.__class__.__name__, self._string) ##############################################
[docs] @classmethod def new_powers(cls): return {unit: 0 for unit in cls.__base_units__}
##############################################
[docs] @classmethod def parse_si(cls, string): si_powers = cls.new_powers() if string: for prefixed_units in string.split('*'): parts = prefixed_units.split('^') unit = parts[0] if len(parts) == 1: powers = 1 else: powers = int(parts[1]) si_powers[unit] += powers return si_powers
##############################################
[docs] @classmethod def to_hash(cls, powers): hash_ = '' for unit in cls.__base_units__: hash_ += str(powers[unit]) return hash_
##############################################
[docs] @classmethod def to_string(cls, si_powers): units = [] for unit in cls.__base_units__: powers = si_powers[unit] if powers == 1: units.append(unit) elif powers > 1 or powers < 0: units.append('{}^{}'.format(unit, powers)) return '*'.join(units)
############################################## # @property
[docs] def is_base_unit(self): count = 0 for powers in self._powers.values(): if powers == 1: count += 1 elif powers != 0: return False return count == 1
############################################## # @property
[docs] def is_unit_less(self): return self._hash == '0'*len(self.__base_units__)
############################################## def __bool__(self): return not self.is_unit_less() ##############################################
[docs] def clone(self): return self.__class__(powers=self._powers)
############################################## def __eq__(self, other): return self._hash == other.hash ############################################## def __ne__(self, other): return self._hash != other.hash ############################################## def __mul__(self, other): powers = {unit: self._powers[unit] + other._powers[unit] for unit in self.__base_units__} return self.__class__(powers=powers) ############################################## def __imul__(self, other): for unit in self.__base_units__: self._powers[unit] += other.powers[unit] self._hash = self.to_hash(self._powers) self._string = self.to_string(self._powers) return self ############################################## def __truediv__(self, other): powers = {unit: self._powers[unit] - other._powers[unit] for unit in self.__base_units__} return self.__class__(powers=powers) ############################################## def __itruediv__(self, other): for unit in self.__base_units__: self._powers[unit] -= other.powers[unit] self._hash = self.to_hash(self._powers) self._string = self.to_string(self._powers) return self ##############################################
[docs] def power(self, value): powers = {unit: self._powers[unit] * value for unit in self.__base_units__} return self.__class__(powers=powers)
##############################################
[docs] def reciprocal(self): return self.power(-1)
##############################################
[docs] def sqrt(self): return self.power(1/2)
##############################################
[docs] def square(self): return self.power(2)
##############################################
[docs] def cbrt(self): return self.power(1/3)
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[docs]class UnitMetaclass(type): """Metaclass to register units""" __units__ = {} __hash_map__ = {} ############################################## def __new__(meta, class_name, base_classes, attributes): cls = type.__new__(meta, class_name, base_classes, attributes) meta.init_unit(cls) meta.register_unit(cls) return cls ##############################################
[docs] @classmethod def init_unit(meta, cls): si_unit = cls.__si_unit__ if not (isinstance(si_unit, SiDerivedUnit) and si_unit): # si_unit is not defined if cls.is_base_unit(): si_unit = SiDerivedUnit(cls.__unit_suffix__) else: # str si_unit = SiDerivedUnit(si_unit) cls.__si_unit__ = si_unit
##############################################
[docs] @classmethod def register_unit(meta, cls): obj = cls() meta.__units__[obj.unit_suffix] = obj if obj.si_unit: hash_ = obj.si_unit.hash if hash_ in meta.__hash_map__: meta.__hash_map__[hash_].append(obj) else: meta.__hash_map__[hash_] = [obj]
##############################################
[docs] @classmethod def unit_iter(meta): return meta.__units__.values()
##############################################
[docs] @classmethod def from_prefix(meta, prefix): return meta._units__.get(prefix, None)
##############################################
[docs] @classmethod def from_hash(meta, hash_): return meta.__hash_map__.get(hash_, None)
##############################################
[docs] @classmethod def from_si_unit(meta, si_unit, unique=True): # Fixme: # - handle power of units # unit -> numpy vector, divide and test for identical factor # define unit, format as V^2 # - complex unit units = meta.__hash_map__.get(si_unit.hash, None) if unique and units is not None: if len(units) > 1: units = [unit for unit in units if unit.is_default_unit()] if len(units) == 1: return units[0] else: raise NameError("Unit clash", units) else: return units[0] else: return units
####################################################################################################
[docs]class UnitError(ValueError): pass
####################################################################################################
[docs]class Unit(metaclass=UnitMetaclass): """This class implements a unit. """ __unit_name__ = '' __unit_suffix__ = '' __quantity__ = '' __si_unit__ = SiDerivedUnit() __default_unit__ = False # __spice_suffix__ = '' _logger = _module_logger.getChild('Unit') ############################################## def __init__(self, si_unit=None): self._unit_name = self.__unit_name__ self._unit_suffix = self.__unit_suffix__ self._quantity = self.__quantity__ if si_unit is None: self._si_unit = self.__si_unit__ else: self._si_unit = si_unit ############################################## def __repr__(self): return '{0}({1})'.format(self.__class__.__name__, str(self)) ############################################## @property def unit_name(self): return self._unit_name @property def unit_suffix(self): return self._unit_suffix @property def quantity(self): return self._quantity @property def si_unit(self): return self._si_unit ############################################## @property def is_unit_less(self): return self._si_unit.is_unit_less() ##############################################
[docs] @classmethod def is_default_unit(cls): return cls.__default_unit__
[docs] @classmethod def is_base_unit(cls): return False
############################################## def __eq__(self, other): """self == other""" return self._si_unit == other.si_unit ############################################## def __ne__(self, other): """self != other""" # The default __ne__ doesn't negate __eq__ until 3.0. return not (self == other) ############################################## def _equivalent_prefixed_unit(self, si_unit): equivalent_unit = PrefixedUnit.from_si_unit(si_unit) if equivalent_unit is not None: return equivalent_unit else: return PrefixedUnit(Unit(si_unit)) ############################################## def _equivalent_unit(self, si_unit): equivalent_unit = UnitMetaclass.from_si_unit(si_unit) if equivalent_unit is not None: return equivalent_unit else: return Unit(si_unit) ############################################## def _equivalent_unit_or_power(self, si_unit, prefixed_unit): if prefixed_unit: return self._equivalent_prefixed_unit(si_unit) else: return self._equivalent_unit(si_unit) ##############################################
[docs] def multiply(self, other, prefixed_unit=False): si_unit = self._si_unit * other.si_unit return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def divide(self, other, prefixed_unit=False): si_unit = self._si_unit / other.si_unit return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def power(self, exponent, prefixed_unit=False): si_unit = self._si_unit.power(exponent) return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def reciprocal(self, prefixed_unit=False): si_unit = self._si_unit.reciprocal() return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def sqrt(self, prefixed_unit=False): si_unit = self._si_unit.sqrt() return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def square(self, prefixed_unit=False): si_unit = self._si_unit.square() return self._equivalent_unit_or_power(si_unit, prefixed_unit)
##############################################
[docs] def cbrt(self, prefixed_unit=False): si_unit = self._si_unit.cbrt() return self._equivalent_unit_or_power(si_unit, prefixed_unit)
############################################## def __str__(self): if self._unit_suffix: return self._unit_suffix else: return str(self._si_unit) ##############################################
[docs] def is_same_unit(self, value): return value.unit == self
##############################################
[docs] def validate(self, value, none=False): if none and value is None: return None if isinstance(value, UnitValue): if self.is_same_unit(value): return value else: raise UnitError else: prefixed_unit = PrefixedUnit.from_prefixed_unit(self) return prefixed_unit.new_value(value)
####################################################################################################
[docs]class SiBaseUnit(Unit): """This class implements an SI base unit.""" ##############################################
[docs] @classmethod def is_base_unit(cls): return True
##############################################
[docs] @classmethod def is_default_unit(cls): return True
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[docs]class PrefixedUnit: """This class implements a prefixed unit. """ __unit_map__ = {} # Prefixed unit singletons __prefixed_unit_map__ = {} __value_ctor__ = None __values_ctor__ = None ##############################################
[docs] @classmethod def register(cls, prefixed_unit): unit = prefixed_unit.unit unit_prefix = prefixed_unit.power if unit_prefix.is_unit and unit.is_default_unit(): key = unit.si_unit.hash # print('Register', key, prefixed_unit) cls.__unit_map__[key] = prefixed_unit if unit.unit_suffix: unit_key = str(unit) else: unit_key = '_' power_key = unit_prefix.power # print('Register', unit_key, power_key, prefixed_unit) if unit_key not in cls.__prefixed_unit_map__: cls.__prefixed_unit_map__[unit_key] = {} cls.__prefixed_unit_map__[unit_key][power_key] = prefixed_unit
##############################################
[docs] @classmethod def from_si_unit(cls, si_unit): return cls.__unit_map__.get(si_unit.hash, None)
##############################################
[docs] @classmethod def from_prefixed_unit(cls, unit, power=0): if unit.unit_suffix: unit_key = str(unit) else: if power == 0: return _simple_prefixed_unit unit_key = '_' try: return cls.__prefixed_unit_map__[unit_key][power] except KeyError: return None
############################################## def __init__(self, unit=None, power=None, value_ctor=None, values_ctor=None): if unit is None: self._unit = Unit() else: self._unit = unit if power is None: self._power = _zero_power else: self._power = power if value_ctor is None: self._value_ctor = self.__value_ctor__ else: self._value_ctor = value_ctor if values_ctor is None: self._values_ctor = self.__values_ctor__ else: self._values_ctor = values_ctor ############################################## def __repr__(self): return '{0}({1})'.format(self.__class__.__name__, str(self)) ############################################## @property def unit(self): return self._unit @property def power(self): return self._power @property def scale(self): return self._power.scale ############################################## @property def is_unit_less(self): return self._unit.is_unit_less ##############################################
[docs] def clone(self): return self.__class__(self._unit, self._power)
##############################################
[docs] def is_same_unit(self, other): return self._unit == other.unit
##############################################
[docs] def check_unit(self, other): if not self.is_same_unit(other): raise UnitError('{} versus {}'.format(self, other))
##############################################
[docs] def is_same_power(self, other): return self._power == other.power
############################################## def __eq__(self, other): """self == other""" return self.is_same_unit(other) and self.is_same_power(other) ############################################## def __ne__(self, other): """self != other""" # The default __ne__ doesn't negate __eq__ until 3.0. return not (self == other) ##############################################
[docs] def str(self, spice=False, unit=True): string = self._power.str(spice) if unit: string += str(self._unit) if spice: # F is interpreted as f = femto if string == 'F': string = '' else: # Ngspice don't support utf-8 string = string.replace('Ω', 'Ohm') # utf-8 cea0 string = string.replace('μ', 'u') # utf-8 cebc return string
##############################################
[docs] def str_spice(self): # Ngspice User Manual Section 2.3.1 Some naming conventions # # Letters immediately following a number that are not scale factors are ignored, and letters # im- mediately following a scale factor are ignored. Hence, 10, 10V, 10Volts, and 10Hz all # represent the same number, and M, MA, MSec, and MMhos all represent the same scale # factor. Note that 1000, 1000.0, 1000Hz, 1e3, 1.0e3, 1kHz, and 1k all represent the same # number. Note that M or m denote ’milli’, i.e. 10−3 . Suffix meg has to be used for 106 . # Fixme: unit clash, e.g. mm ??? return self.str(spice=True, unit=True)
############################################## def __str__(self): return self.str(spice=False, unit=True) ##############################################
[docs] def new_value(self, value): if isinstance(value, np.ndarray): return self._values_ctor.from_ndarray(value, self) elif isinstance(value, collections.Iterable): return [self._value_ctor(self, x) for x in value] else: return self._value_ctor(self, value)
####################################################################################################
[docs]class UnitValue: # numbers.Real """This class implements a value with a unit and a power (prefix). The value is not converted to float if the value is an int. """ _logger = _module_logger.getChild('UnitValue') ##############################################
[docs] @classmethod def simple_value(cls, value): return cls(_simple_prefixed_unit, value)
############################################## def __init__(self, prefixed_unit, value): self._prefixed_unit = prefixed_unit if isinstance(value, UnitValue): # Fixme: anonymous ??? if not self.is_same_unit(value): raise UnitError if self.is_same_power(value): self._value = value.value else: self._value = self._convert_scalar_value(value) elif isinstance(value, int): self._value = value # to keep as int else: self._value = float(value) ############################################## def __repr__(self): return '{0}({1})'.format(self.__class__.__name__, str(self)) ############################################## @property def prefixed_unit(self): return self._prefixed_unit @property def unit(self): return self._prefixed_unit.unit @property def power(self): return self._prefixed_unit.power @property def scale(self): return self._prefixed_unit.power.scale @property def value(self): return self._value ##############################################
[docs] def clone(self): return self.__class__(self._prefixed_unit, self._value)
##############################################
[docs] def clone_prefixed_unit(self, value): return self.__class__(self._prefixed_unit, value)
############################################## # def to_unit_values(self): # return self._prefixed_unit.new_value(self._value) ############################################## # def clone_unit(self, value, power): # return self.__class__(PrefixedUnit(self.unit, power), value) ##############################################
[docs] def is_same_unit(self, other): return self._prefixed_unit.is_same_unit(other.prefixed_unit)
############################################## def _check_unit(self, other): if not self.is_same_unit(other): raise UnitError ##############################################
[docs] def is_same_power(self, other): return self._prefixed_unit.is_same_power(other.prefixed_unit)
############################################## def __eq__(self, other): """self == other""" if isinstance(other, UnitValue): return self.is_same_unit(other) and float(self) == float(other) else: return float(self) == float(other) ############################################## def __ne__(self, other): """self != other""" # The default __ne__ doesn't negate __eq__ until 3.0. return not (self == other) ############################################## def _convert_value(self, other): """Convert the value of other to the power of self.""" self._check_unit(other) if self.is_same_power(other): return other.value else: return other.value * (other.scale / self.scale) # for numerical precision ############################################## def _convert_scalar_value(self, value): return float(value) / self.scale ############################################## def __int__(self): return int(self._value * self.scale) ############################################## def __float__(self): return float(self._value * self.scale) ##############################################
[docs] def str(self, spice=False, space=False, unit=True): string = str(self._value) if space: string += ' ' string += self._prefixed_unit.str(spice, unit) return string
##############################################
[docs] def str_space(self): return self.str(space=True)
##############################################
[docs] def str_spice(self): return self.str(spice=True, space=False, unit=True)
############################################## def __str__(self): return self.str(spice=False, space=True, unit=True) ############################################## def __bool__(self): """True if self != 0. Called for bool(self).""" return self._value != 0 ############################################## def __add__(self, other): """self + other""" if (isinstance(other, UnitValue)): self._check_unit(other) new_obj = self.clone() new_obj._value += self._convert_value(other) return new_obj else: return float(self) + other ############################################## def __iadd__(self, other): """self += other""" self._check_unit(other) self._value += self._convert_value(other) return self ############################################## def __radd__(self, other): """other + self""" return float(self) + other ############################################## def __neg__(self): """-self""" return self.clone_prefixed_unit(-self._value) ############################################## def __pos__(self): """+self""" return self.clone() ############################################## def __sub__(self, other): """self - other""" if (isinstance(other, UnitValue)): self._check_unit(other) new_obj = self.clone() new_obj._value -= self._convert_value(other) return new_obj else: return float(self) - other ############################################## def __isub__(self, other): """self -= other""" self._check_unit(other) self._value -= self._convert_value(other) return self ############################################## def __rsub__(self, other): """other - self""" return other - float(self) ############################################## def __mul__(self, other): """self * other""" if (isinstance(other, UnitValue)): equivalent_unit = self.unit.multiply(other.unit, True) value = float(self) * float(other) return equivalent_unit.new_value(value) else: try: # scale value scalar = float(other) new_obj = self.clone() new_obj._value *= scalar return new_obj except (ValueError, TypeError): # Numpy raises TypeError return float(self) * other ############################################## def __imul__(self, other): """self *= other""" if (isinstance(other, UnitValue)): raise UnitError else: # scale value # Fixme: right ? self._value *= self._convert_value(other) return self ############################################## def __rmul__(self, other): """other * self""" if (isinstance(other, UnitValue)): raise NotImplementedError # Fixme: when ??? else: # scale value return self.__mul__(other) ############################################## def __floordiv__(self, other): """self // other """ if (isinstance(other, UnitValue)): equivalent_unit = self.unit.divide(other.unit, True) value = float(self) // float(other) return equivalent_unit.new_value(value) else: try: # scale value scalar = float(other) new_obj = self.clone() new_obj._value //= scalar return new_obj except (ValueError, TypeError): # Numpy raises TypeError return float(self) // other ############################################## def __ifloordiv__(self, other): """self //= other """ if (isinstance(other, UnitValue)): raise NotImplementedError else: # scale value self._value //= float(other) return self ############################################## def __rfloordiv__(self, other): """other // self""" if (isinstance(other, UnitValue)): raise NotImplementedError # Fixme: when ??? else: # scale value return other // float(self) ############################################## def __truediv__(self, other): """self / other""" if (isinstance(other, UnitValue)): equivalent_unit = self.unit.divide(other.unit, True) value = float(self) / float(other) return equivalent_unit.new_value(value) else: try: # scale value scalar = float(other) new_obj = self.clone() new_obj._value /= scalar return new_obj except (ValueError, TypeError): # Numpy raises TypeError return float(self) / other ############################################## def __itruediv__(self, other): """self /= other""" if (isinstance(other, UnitValue)): raise NotImplementedError else: # scale value self._value /= float(other) return self ############################################## def __rtruediv__(self, other): """other / self""" if (isinstance(other, UnitValue)): raise NotImplementedError # Fixme: when ??? else: # scale value return other / float(self) ############################################## def __pow__(self, exponent): """self**exponent; should promote to float or complex when necessary.""" new_obj = self.clone() new_obj._value **= float(exponent) return new_obj ############################################## def __ipow__(self, exponent): self._value **= float(exponent) return self ############################################## def __rpow__(self, base): """base ** self""" raise NotImplementedError ############################################## def __abs__(self): """Returns the Real distance from 0. Called for abs(self).""" return self.clone_prefixed_unit(abs(self._value)) ############################################## def __trunc__(self): """trunc(self): Truncates self to an Integral. Returns an Integral i such that: * i>0 iff self>0; * abs(i) <= abs(self); * for any Integral j satisfying the first two conditions, abs(i) >= abs(j) [i.e. i has "maximal" abs among those]. i.e. "truncate towards 0". """ raise NotImplementedError ############################################## def __divmod__(self, other): """divmod(self, other): The pair (self // other, self % other). Sometimes this can be computed faster than the pair of operations. """ return (self // other, self % other) ############################################## def __rdivmod__(self, other): """divmod(other, self): The pair (self // other, self % other). Sometimes this can be computed faster than the pair of operations. """ return (other // self, other % self) ############################################## def __mod__(self, other): """self % other""" raise NotImplementedError ############################################## def __rmod__(self, other): """other % self""" raise NotImplementedError ############################################## def __lt__(self, other): """self < other < on Reals defines a total ordering, except perhaps for NaN.""" return float(self) < float(other) ############################################## def __le__(self, other): """self <= other""" return float(self) <= float(other) ############################################## def __ceil__(self): return math.ceil(float(self)) ############################################## def __floor__(self): return math.floor(float(self)) ############################################## def __round__(self): return round(float(self)) ##############################################
[docs] def reciprocal(self): equivalent_unit = self.unit.reciprocal(prefixed_unit=True) reciprocal_value = 1. / float(self) return equivalent_unit.new_value(reciprocal_value)
##############################################
[docs] def get_prefixed_unit(self, power=0): prefixed_unit = PrefixedUnit.from_prefixed_unit(self.unit, power) if prefixed_unit is not None: return prefixed_unit else: raise NameError("Prefixed unit not found for {} and power {}".format(self, power))
##############################################
[docs] def convert(self, prefixed_unit): """Convert the value to another power.""" self._prefixed_unit.check_unit(prefixed_unit) if self._prefixed_unit.is_same_power(prefixed_unit): return self else: value = float(self) / prefixed_unit.scale return prefixed_unit.new_value(value)
##############################################
[docs] def convert_to_power(self, power=0): """Convert the value to another power.""" if power == 0: value = float(self) else: value = float(self) / 10**power return self.get_prefixed_unit(power).new_value(value)
##############################################
[docs] def canonise(self): # log10(10**n) = n log10(1) = 0 log10(10**-n) = -n log10(0) = -oo try: abs_value = abs(float(self)) log = math.log(abs_value)/math.log(1000) # if abs_value >= 1: # power = 3 * int(log) # else: # if log - int(log): # frac # power = 3 * (int(log) -1) # else: # power = 3 * int(log) power = int(log) if abs_value < 1 and (log - int(log)): power -= 1 power *= 3 # print('Unit.canonise', self, self._value, int(self._power), '->', float(self), power) if power == int(self.power): # print('Unit.canonise noting to do for', self) return self else: # print('Unit.canonise convert', self, 'to', power) # print('Unit.canonise convert', self, 'to', Unit) return self.convert_to_power(power) except Exception as e: # Fixme: fallback self._logger.warning(e) return self
####################################################################################################
[docs]class UnitValues(np.ndarray): """This class implements a Numpy array with a unit and a power (prefix). """ _logger = _module_logger.getChild('UnitValues') CONVERSION = EnumFactory('ConversionType', ( 'NOT_IMPLEMENTED', 'NO_CONVERSION', 'FLOAT', 'UNIT_MATCH', 'UNIT_MATCH_NO_OUT_CAST', 'NEW_UNIT' )) # Reference_documentation: # https://docs.scipy.org/doc/numpy-1.13.0/reference/arrays.ndarray.html # https://docs.scipy.org/doc/numpy-1.13.0/user/basics.subclassing.html # https://docs.scipy.org/doc/numpy-1.13.0/reference/ufuncs.html UFUNC_MAP = { # Math operations # -------------------------------------------------- np.add: CONVERSION.UNIT_MATCH, np.subtract: CONVERSION.UNIT_MATCH, np.multiply: CONVERSION.NEW_UNIT, np.divide: CONVERSION.NEW_UNIT, np.logaddexp: CONVERSION.FLOAT, np.logaddexp2: CONVERSION.FLOAT, np.true_divide: CONVERSION.NEW_UNIT, np.floor_divide: CONVERSION.NEW_UNIT, np.negative: CONVERSION.NO_CONVERSION, np.positive: CONVERSION.NO_CONVERSION, np.power: CONVERSION.NEW_UNIT, np.remainder: CONVERSION.UNIT_MATCH, np.mod: CONVERSION.UNIT_MATCH, np.fmod: CONVERSION.UNIT_MATCH, np.divmod: CONVERSION.UNIT_MATCH, np.absolute: CONVERSION.NO_CONVERSION, np.fabs: CONVERSION.NO_CONVERSION, np.rint: CONVERSION.NO_CONVERSION, np.sign: CONVERSION.NO_CONVERSION, np.heaviside: CONVERSION.NOT_IMPLEMENTED, # ! np.conj: CONVERSION.NOT_IMPLEMENTED, # ! np.exp: CONVERSION.FLOAT, np.exp2: CONVERSION.FLOAT, np.log: CONVERSION.FLOAT, np.log2: CONVERSION.FLOAT, np.log10: CONVERSION.FLOAT, np.expm1: CONVERSION.FLOAT, np.log1p: CONVERSION.FLOAT, np.sqrt: CONVERSION.NEW_UNIT, np.square: CONVERSION.NEW_UNIT, np.cbrt: CONVERSION.NEW_UNIT, np.reciprocal: CONVERSION.NEW_UNIT, # Trigonometric functions # -------------------------------------------------- np.sin: CONVERSION.FLOAT, np.cos: CONVERSION.FLOAT, np.tan: CONVERSION.FLOAT, np.arcsin: CONVERSION.FLOAT, np.arccos: CONVERSION.FLOAT, np.arctan: CONVERSION.FLOAT, np.arctan2: CONVERSION.FLOAT, np.hypot: CONVERSION.FLOAT, np.sinh: CONVERSION.FLOAT, np.cosh: CONVERSION.FLOAT, np.tanh: CONVERSION.FLOAT, np.arcsinh: CONVERSION.FLOAT, np.arccosh: CONVERSION.FLOAT, np.arctanh: CONVERSION.FLOAT, np.deg2rad: CONVERSION.FLOAT, np.rad2deg: CONVERSION.FLOAT, # Bit-twiddling functions # -------------------------------------------------- np.bitwise_and: CONVERSION.NOT_IMPLEMENTED, # Nonsense np.bitwise_or: CONVERSION.NOT_IMPLEMENTED, # Nonsense np.bitwise_xor: CONVERSION.NOT_IMPLEMENTED, # Nonsense np.invert: CONVERSION.NOT_IMPLEMENTED, # Nonsense np.left_shift: CONVERSION.NOT_IMPLEMENTED, # Nonsense np.right_shift: CONVERSION.NOT_IMPLEMENTED, # Nonsense # Comparison functions # -------------------------------------------------- np.greater: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.greater_equal: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.less: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.less_equal: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.not_equal: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.equal: CONVERSION.UNIT_MATCH_NO_OUT_CAST, np.logical_and: CONVERSION.UNIT_MATCH, np.logical_or: CONVERSION.UNIT_MATCH, np.logical_xor: CONVERSION.UNIT_MATCH, np.logical_not: CONVERSION.UNIT_MATCH, np.maximum: CONVERSION.UNIT_MATCH, np.minimum: CONVERSION.UNIT_MATCH, np.fmax: CONVERSION.UNIT_MATCH, np.fmin: CONVERSION.UNIT_MATCH, # Floating functions # -------------------------------------------------- np.isfinite: CONVERSION.NOT_IMPLEMENTED, # ! _T np.isinf: CONVERSION.NOT_IMPLEMENTED, # ! _T np.isnan: CONVERSION.NOT_IMPLEMENTED, # ! _T np.fabs: CONVERSION.NOT_IMPLEMENTED, # ! _ np.signbit: CONVERSION.NOT_IMPLEMENTED, # ! _T np.copysign: CONVERSION.NOT_IMPLEMENTED, # ! np.nextafter: CONVERSION.NOT_IMPLEMENTED, # ! np.spacing: CONVERSION.NOT_IMPLEMENTED, # ! np.modf: CONVERSION.NOT_IMPLEMENTED, # ! np.ldexp: CONVERSION.NOT_IMPLEMENTED, # ! np.frexp: CONVERSION.NOT_IMPLEMENTED, # ! np.fmod: CONVERSION.NOT_IMPLEMENTED, # ! np.floor: CONVERSION.NOT_IMPLEMENTED, # ! np.ceil: CONVERSION.NO_CONVERSION, np.trunc: CONVERSION.NO_CONVERSION, } ##############################################
[docs] @classmethod def from_ndarray(cls, array, prefixed_unit): # cls._logger.info('UnitValues.__new__ ' + str((cls, array, prefixed_unit))) # obj = cls(prefixed_unit, array.shape, array.dtype) # Fixme: buffer ??? # obj[...] = array[...] obj = array.view(UnitValues) obj._prefixed_unit = prefixed_unit if isinstance(array, UnitValues): return array.convert(prefixed_unit) return obj
############################################## def __new__(cls, prefixed_unit, shape, dtype=float, buffer=None, offset=0, strides=None, order=None): # Called for explicit constructor # obj = UnitValues(prefixed_unit, shape) # cls._logger.info('UnitValues.__new__ ' + str((cls, prefixed_unit, shape, dtype, buffer, offset, strides, order))) obj = super(UnitValues, cls).__new__(cls, shape, dtype, buffer, offset, strides, order) # obj = np.asarray(input_array).view(cls) obj._prefixed_unit = prefixed_unit return obj ############################################## def __array_finalize__(self, obj): # self._logger.info('UnitValues.__new__ ' + '\n {}'.format(obj)) # self is a new object resulting from ndarray.__new__(UnitValues, ...) # therefore it only has attributes that the ndarray.__new__ constructor gave it # i.e. those of a standard ndarray. # We could have got to the ndarray.__new__ call in 3 ways: # From an explicit constructor - e.g. UnitValues(): # obj is None # we are in the middle of the UnitValues.__new__ constructor if obj is None: return # From view casting - e.g arr.view(UnitValues): # obj is arr # type(obj) can be UnitValues # From new-from-template - e.g infoarr[:3] # type(obj) is UnitValues self._prefixed_unit = getattr(obj, '_prefixed_unit', None) # Fixme: None ############################################## def __array_ufunc__(self, ufunc, method, *inputs, **kwargs): # - "ufunc" is the ufunc object that was called # - "method" is a string indicating how the ufunc was called, either # "__call__" to indicate it was called directly, # or one of its "ufuncs.methods": "reduce", "accumulate", "reduceat", "outer", or "at". # - "inputs" is a tuple of the input arguments to the ufunc # - "kwargs" contains any optional or keyword arguments passed to the function. # This includes any *out* arguments, which are always contained in a tuple. # ufunc.reduce(a[, axis, dtype, out, keepdims]) Reduces a‘s dimension by one, by applying ufunc along one axis. # ufunc.accumulate(array[, axis, dtype, out, ...]) Accumulate the result of applying the operator to all elements. # ufunc.reduceat(a, indices[, axis, dtype, out]) Performs a (local) reduce with specified slices over a single axis. # ufunc.outer(A, B, **kwargs) Apply the ufunc op to all pairs (a, b) with a in A and b in B. # ufunc.at(a, indices[, b]) Performs unbuffered in place operation on operand ‘a’ for elements specified by ‘indices’. # self._logger.info( # '\n self={}\n ufunc={}\n method={}\n inputs={}\n kwargs={}' # .format(self, ufunc, method, inputs, kwargs)) # ufunc=<ufunc 'multiply'> # method=__call__ # inputs=(UnitValues(mV, [0 1 2 3 4 5 6 7 8 9]), 2) # ufunc=<ufunc 'sin'> # method=__call__ # inputs=(UnitValues(mV, [0 1 2 3 4 5 6 7 8 9]),) # kwargs={} # ufunc=<ufunc 'add'> # method=__call__ # inputs=(UnitValues(mV, [0 1 2 3 4 5 6 7 8 9]), UnitValues(mV, [0 1 2 3 4 5 6 7 8 9])) prefixed_unit = self._prefixed_unit conversion = self.UFUNC_MAP[ufunc] self._logger.info("Conversion for {} is {}".format(ufunc, conversion)) # Cast inputs to ndarray args = [] if conversion == self.CONVERSION.NO_CONVERSION: # should be 1 arg args = [( input_.as_ndarray(False) if isinstance(input_, UnitValues) else input_ ) for input_ in inputs] # elif conversion == self.CONVERSION.FLOAT: if not prefixed_unit.is_unit_less: # raise ValueError("Must be unit less") self._logger.warning("Should be unit less") args = [( input_.as_ndarray(True) if isinstance(input_, UnitValues) else input_ ) for input_ in inputs] # elif conversion in (self.CONVERSION.UNIT_MATCH, self.CONVERSION.UNIT_MATCH_NO_OUT_CAST): # len(inputs) == 2 other = inputs[1] if isinstance(other, (UnitValues, UnitValue)): self._check_unit(other) args.append(self.as_ndarray()) nd_other = self._convert_value(other) if isinstance(other, UnitValues): nd_other = nd_other.as_ndarray() elif isinstance(other, UnitValue): nd_other = float(nd_other) args.append(nd_other) else: raise ValueError # elif conversion == self.CONVERSION.NEW_UNIT: if len(inputs) == 1: #! Fixme: power if ufunc == np.sqrt: prefixed_unit = self.unit.sqrt(True) elif ufunc == np.square: prefixed_unit = self.unit.square(True) elif ufunc == np.cbrt: prefixed_unit = self.unit.cbrt(True) elif ufunc == np.reciprocal: prefixed_unit = self.unit.reciprocal(True) else: raise NotImplementedError args.append(self.as_ndarray(True)) elif len(inputs) == 2: other = inputs[1] if isinstance(other, (UnitValues, UnitValue)): if ufunc == np.multiply: prefixed_unit = self.unit.multiply(other.unit, True) elif ufunc in (np.divide, np.true_divide, np.floor_divide): prefixed_unit = self.unit.divide(other.unit, True) else: raise NotImplementedError args.append(self.as_ndarray(True)) if isinstance(other, UnitValue): args.append(float(other)) else: args.append(other.as_ndarray(True)) elif ufunc in (np.multiply, np.divide, np.true_divide, np.floor_divide, np.power): if ufunc == np.power: prefixed_unit = self.unit.power(other, True) args.append(self.as_ndarray()) args.append(other) else: raise NotImplementedError else: raise NotImplementedError # else: # self.CONVERSION.NOT_IMPLEMENTED raise NotImplementedError # self._logger.info("Output unit is {}".format(prefixed_unit)) # Cast outputs to ndarray outputs = kwargs.pop('out', None) if outputs: out_args = [] for output in outputs: if isinstance(output, UnitValues): out_args.append(output.as_ndarray()) else: out_args.append(output) kwargs['out'] = tuple(out_args) else: outputs = (None,) * ufunc.nout # Call ufunc results = super(UnitValues, self).__array_ufunc__(ufunc, method, *args, **kwargs) if results is NotImplemented: return NotImplemented # ensure results is a tuple if ufunc.nout == 1: results = (results,) # Cast results if conversion in (self.CONVERSION.FLOAT, self.CONVERSION.UNIT_MATCH_NO_OUT_CAST): # Fixme: ok ??? results = tuple(( result if output is None else output ) for result, output in zip(results, outputs)) else: results = tuple(( UnitValues.from_ndarray(np.asarray(result), prefixed_unit) if output is None else output ) for result, output in zip(results, outputs)) # list or scalar return results[0] if len(results) == 1 else results ############################################## # def __array_wrap__(self, out_array, context=None): # # self._logger.info('\n self={}\n out_array={}\n context={}'.format(self, out_array, context)) # # return super(UnitValues, self).__array_wrap__(out_array, context) ##############################################
[docs] def as_ndarray(self, scale=False): array = self.view(np.ndarray) if scale: return array * self.scale else: return array
############################################## def __getitem__(self, _slice): value = super(UnitValues, self).__getitem__(_slice) if isinstance(value, UnitValue): # slice return value else: return self._prefixed_unit.new_value(value) ############################################## def __setitem__(self, _slice, value): if isinstance(value, UnitValue): self._check_unit(value) value = self._convert_value(value).value elif isinstance(value, UnitValues): self._check_unit(value) value = self._convert_value(value) super(UnitValues, self).__setitem__(_slice, value) ############################################## def __contains__(self, value): raise NotImplementedError ############################################## def __repr__(self): # return repr(self.as_ndarray()) return '{}({})'.format(self.__class__.__name__, str(self)) ############################################## @property def prefixed_unit(self): return self._prefixed_unit @property def unit(self): return self._prefixed_unit.unit @property def power(self): return self._prefixed_unit.power @property def scale(self): return self._prefixed_unit.power.scale ##############################################
[docs] def is_same_unit(self, other): return self._prefixed_unit.is_same_unit(other.prefixed_unit)
############################################## def _check_unit(self, other): if not self.is_same_unit(other): raise UnitError ##############################################
[docs] def is_same_power(self, other): return self._prefixed_unit.is_same_power(other.prefixed_unit)
############################################## def __eq__(self, other): """self == other""" if isinstance(other, UnitValues): return self.is_same_unit(other) and self.as_ndarray() == other.as_ndarray() else: raise ValueError ############################################## def _convert_value(self, other): """Convert the value of other to the power of self.""" self._check_unit(other) if self.is_same_power(other): return other else: return other * (other.scale / self.scale) # for numerical precision ############################################## def __str__(self): return str(self.as_ndarray()) + '@' + str(self._prefixed_unit) ##############################################
[docs] def reciprocal(self): equivalent_unit = self.unit.reciprocal(prefixed_unit=True) reciprocal_value = 1. / np.as_ndarray(True) return self.from_ndarray(reciprocal_value, equivalent_unit)
##############################################
[docs] def get_prefixed_unit(self, power=0): prefixed_unit = PrefixedUnit.from_prefixed_unit(self.unit, power) if prefixed_unit is not None: return prefixed_unit else: raise NameError("Prefixed unit not found for {} and power {}".format(self, power))
##############################################
[docs] def convert(self, prefixed_unit): """Convert the value to another power.""" self._prefixed_unit.check_unit(prefixed_unit) if self._prefixed_unit.is_same_power(prefixed_unit): return self else: value = self.as_ndarray(True) / prefixed_unit.scale return prefixed_unit.new_value(value)
##############################################
[docs] def convert_to_power(self, power=0): """Convert the value to another power.""" value = self.as_ndarray(True) if power != 0: value /= 10**power return self.get_prefixed_unit(power).new_value(value)
#################################################################################################### # Reset PrefixedUnit.__value_ctor__ = UnitValue _simple_prefixed_unit = PrefixedUnit() ####################################################################################################
[docs]class FrequencyMixin: """ This class implements a frequency mixin. """ ############################################## @property def period(self): r""" Return the period :math:`T = \frac{1}{f}`. """ return self.reciprocal() ############################################## @property def pulsation(self): r""" Return the pulsation :math:`\omega = 2\pi f`. """ # Fixme: UnitValues return float(self * 2 * math.pi)
####################################################################################################
[docs]class PeriodMixin: """ This class implements a period mixin. """ ############################################## @property def frequency(self): r""" Return the period :math:`f = \frac{1}{T}`. """ return self.reciprocal() ############################################## @property def pulsation(self): r""" Return the pulsation :math:`\omega = \frac{2\pi}{T}`. """ return self.frequency.pulsation