class_docstr: Base class to represent the So2 group.
  
  The SO(2) is the group of all rotations about the origin of two-dimensional Euclidean space
  :math:`R^2` under the operation of composition.
  See more: https://en.wikipedia.org/wiki/Orthogonal_group#Special_orthogonal_group
  
  We internally represent the rotation by a complex number.
  
  Example:
      >>> real = torch.tensor([1.0])
      >>> imag = torch.tensor([2.0])
      >>> So2(torch.complex(real, imag))
      Parameter containing:
      tensor([1.+2.j], requires_grad=True)
docstr: Converts elements of lie algebra to elements of lie group.
  
  Args:
      theta: angle in radians of shape :math:`(B, 1)` or :math:`(B)`.
  
  Example:
      >>> v = torch.tensor([3.1415/2])
      >>> s = So2.exp(v)
      >>> s
      Parameter containing:
      tensor([4.6329e-05+1.j], requires_grad=True)
docstr_tok: ["Converts","elements","of","lie","algebra","to","elements","of","lie","group",".","Args",":","theta",":","angle","in","radians","of","shape",":","math",":","`","(","B",",","1",")","`","or",":","math",":","`","(","B",")","`",".","Example",":",">",">",">","v","=","torch.tensor","(","[","3.1415\/2","]",")",">",">",">","s","=","So2.exp","(","v",")",">",">",">","s","Parameter","containing",":","tensor","(","[","4.6329e-05+1.j","]",",","requires_grad=True",")"]
code: def exp(theta: Tensor) -> So2:
      """Converts elements of lie algebra to elements of lie group.
  
      Args:
          theta: angle in radians of shape :math:`(B, 1)` or :math:`(B)`.
  
      Example:
          >>> v = torch.tensor([3.1415/2])
          >>> s = So2.exp(v)
          >>> s
          Parameter containing:
          tensor([4.6329e-05+1.j], requires_grad=True)
      """
      # TODO change to KORNIA_CHECK_SHAPE once there is multiple shape support
      check_so2_theta_shape(theta)
      return So2(complex(theta.cos(), theta.sin()))
  
imports: from __future__ import annotations
  from typing import Optional, overload
  from kornia.core import Device, Dtype, Module, Parameter, Tensor, complex, rand, stack, tensor, zeros_like
  from kornia.core.check import KORNIA_CHECK, KORNIA_CHECK_IS_TENSOR
  from kornia.geometry.liegroup._utils import check_so2_matrix, check_so2_matrix_shape, check_so2_t_shape, check_so2_theta_shape, check_so2_z_shape
  from kornia.geometry.vector import Vector2
label_desc: Use image node_id 8 for calling the So2 obj's underlying member method code with example usage: obj.exp(theta) and returns: So2