Source code for sym.unit3

# -----------------------------------------------------------------------------
# This file was autogenerated by symforce from template:
#     geo_package/CLASS.py.jinja
# Do NOT modify by hand.
# -----------------------------------------------------------------------------


# ruff: noqa: PLR0915, F401, PLW0211, PLR0914

import math
import random
import typing as T

import numpy

from .rot3 import Rot3

# isort: split
from .ops import unit3 as ops


[docs]class Unit3(object): """ Autogenerated Python implementation of :py:class:`symforce.geo.unit3.Unit3`. Direction in R^3, represented as a :class:`Rot3 <symforce.geo.rot3.Rot3>` that transforms [0, 0, 1] to the desired direction. The storage is therefore a quaternion and the tangent space is 2 dimensional. Most operations are implemented using operations from :class:`Rot3 <symforce.geo.rot3.Rot3>`. Note: an alternative implementation could directly store a unit vector and define its boxplus manifold as described in Appendix B.2 of [Hertzberg 2013]. This can be done by finding the Householder reflector of x and use it to transform the exponential map of delta, which is a small perturbation in the tangent space (R^2). Namely:: x.retract(delta) = x [+] delta = Rx * Exp(delta), where Exp(delta) = [sinc(||delta||) * delta, cos(||delta||)], and Rx = (I - 2 vv^T / (v^Tv))X, v = x - e_z != 0, X is a matrix negating 2nd vector component = I , x = e_z [Hertzberg 2013] Integrating Generic Sensor Fusion Algorithms with Sound State Representations through Encapsulation of Manifolds """ __slots__ = ["data"] def __repr__(self): # type: () -> str return "<{} {}>".format(self.__class__.__name__, self.data) # -------------------------------------------------------------------------- # Handwritten methods included from "custom_methods/unit3.py.jinja" # -------------------------------------------------------------------------- def __init__(self, rot3=None): # type: (T.Optional[Rot3]) -> None if rot3 is None: self.data = ops.GroupOps.identity().data # type: T.List[float] else: self.data = rot3.data # -------------------------------------------------------------------------- # Custom generated methods # --------------------------------------------------------------------------
[docs] @staticmethod def from_vector(a, epsilon): # type: (numpy.ndarray, float) -> Unit3 """ Return a :class:`Unit3` that points along the direction of vector ``a`` ``a`` does not have to be a unit vector. """ # Total ops: 35 # Input arrays if a.shape == (3,): a = a.reshape((3, 1)) elif a.shape != (3, 1): raise IndexError( "a is expected to have shape (3, 1) or (3,); instead had shape {}".format(a.shape) ) # Intermediate terms (8) _tmp0 = 1 / math.sqrt(a[0, 0] ** 2 + a[1, 0] ** 2 + a[2, 0] ** 2 + epsilon) _tmp1 = _tmp0 * a[2, 0] _tmp2 = math.sqrt(2 * _tmp1 + epsilon + 2) _tmp3 = ( 0.0 if -epsilon + abs(_tmp1 + 1) == 0 else math.copysign(1, -epsilon + abs(_tmp1 + 1)) ) + 1 _tmp4 = (1.0 / 2.0) * _tmp3 _tmp5 = _tmp0 * _tmp4 / _tmp2 _tmp6 = 1.0 / 2.0 - 1.0 / 2.0 * ( 0.0 if 1 - epsilon**2 == 0 else math.copysign(1, 1 - epsilon**2) ) _tmp7 = 1 - _tmp4 # Output terms _res = [0.0] * 4 _res[0] = -_tmp5 * a[1, 0] + _tmp7 * (1 - _tmp6) _res[1] = _tmp5 * a[0, 0] + _tmp6 * _tmp7 _res[2] = 0 _res[3] = (1.0 / 4.0) * _tmp2 * _tmp3 return Unit3.from_storage(_res)
[docs] def to_unit_vector(self): # type: (Unit3) -> numpy.ndarray """ This function was autogenerated from a symbolic function. Do not modify by hand. Symbolic function: to_unit_vector Args: Outputs: res: Matrix31 """ # Total ops: 14 # Input arrays _self = self.data # Intermediate terms (2) _tmp0 = 2 * _self[1] _tmp1 = 2 * _self[0] # Output terms _res = numpy.zeros(3) _res[0] = _self[2] * _tmp1 + _self[3] * _tmp0 _res[1] = _self[2] * _tmp0 - _self[3] * _tmp1 _res[2] = -2 * _self[0] ** 2 - 2 * _self[1] ** 2 + 1 return _res
[docs] def to_rotation(self): # type: (Unit3) -> Rot3 """ This function was autogenerated from a symbolic function. Do not modify by hand. Symbolic function: to_rotation Args: Outputs: res: Rot3 """ # Total ops: 0 # Input arrays _self = self.data # Intermediate terms (0) # Output terms _res = [0.0] * 4 _res[0] = _self[0] _res[1] = _self[1] _res[2] = _self[2] _res[3] = _self[3] return Rot3.from_storage(_res)
# -------------------------------------------------------------------------- # StorageOps concept # --------------------------------------------------------------------------
[docs] @staticmethod def storage_dim(): # type: () -> int return 4
[docs] def to_storage(self): # type: () -> T.List[float] return list(self.data)
[docs] @classmethod def from_storage(cls, vec): # type: (T.Sequence[float]) -> Unit3 instance = cls.__new__(cls) if isinstance(vec, list): instance.data = vec else: instance.data = list(vec) if len(vec) != cls.storage_dim(): raise ValueError( "{} has storage dim {}, got {}.".format(cls.__name__, cls.storage_dim(), len(vec)) ) return instance
# -------------------------------------------------------------------------- # GroupOps concept # --------------------------------------------------------------------------
[docs] @classmethod def identity(cls): # type: () -> Unit3 return ops.GroupOps.identity()
[docs] def inverse(self): # type: () -> Unit3 return ops.GroupOps.inverse(self)
[docs] def compose(self, b): # type: (Unit3) -> Unit3 return ops.GroupOps.compose(self, b)
[docs] def between(self, b): # type: (Unit3) -> Unit3 return ops.GroupOps.between(self, b)
# -------------------------------------------------------------------------- # LieGroupOps concept # --------------------------------------------------------------------------
[docs] @staticmethod def tangent_dim(): # type: () -> int return 2
[docs] @classmethod def from_tangent(cls, vec, epsilon=1e-8): # type: (numpy.ndarray, float) -> Unit3 if len(vec) != cls.tangent_dim(): raise ValueError( "Vector dimension ({}) not equal to tangent space dimension ({}).".format( len(vec), cls.tangent_dim() ) ) return ops.LieGroupOps.from_tangent(vec, epsilon)
[docs] def to_tangent(self, epsilon=1e-8): # type: (float) -> numpy.ndarray return ops.LieGroupOps.to_tangent(self, epsilon)
[docs] def retract(self, vec, epsilon=1e-8): # type: (numpy.ndarray, float) -> Unit3 if len(vec) != self.tangent_dim(): raise ValueError( "Vector dimension ({}) not equal to tangent space dimension ({}).".format( len(vec), self.tangent_dim() ) ) return ops.LieGroupOps.retract(self, vec, epsilon)
[docs] def local_coordinates(self, b, epsilon=1e-8): # type: (Unit3, float) -> numpy.ndarray return ops.LieGroupOps.local_coordinates(self, b, epsilon)
[docs] def interpolate(self, b, alpha, epsilon=1e-8): # type: (Unit3, float, float) -> Unit3 return ops.LieGroupOps.interpolate(self, b, alpha, epsilon)
# -------------------------------------------------------------------------- # General Helpers # -------------------------------------------------------------------------- def __eq__(self, other): # type: (T.Any) -> bool if isinstance(other, Unit3): return self.data == other.data else: return False @T.overload def __mul__(self, other): # pragma: no cover # type: (Unit3) -> Unit3 pass @T.overload def __mul__(self, other): # pragma: no cover # type: (numpy.ndarray) -> numpy.ndarray pass def __mul__(self, other): # type: (T.Union[Unit3, numpy.ndarray]) -> T.Union[Unit3, numpy.ndarray] if isinstance(other, Unit3): return self.compose(other) elif isinstance(other, numpy.ndarray) and hasattr(self, "compose_with_point"): return self.compose_with_point(other).reshape(other.shape) else: raise NotImplementedError("Cannot compose {} with {}.".format(type(self), type(other)))