grss.prop.prop_unscented.SigmaPoints

grss.prop.prop_unscented.SigmaPoints#

class grss.prop.prop_unscented.SigmaPoints(x_dict, cov, sp_type, alpha=None, beta=None, kappa=None, sqrt_func=None)#

Bases: object

Class for representing sigma points for the unscented transformation.

__init__(x_dict, cov, sp_type, alpha=None, beta=None, kappa=None, sqrt_func=None)#

Initialize a sigma point object.

Parameters:
  • x_dict (dict) – solution dictionary containing cometary/cartesian elements

  • cov (numpy.ndarray) – covariance matrix of the solution

  • sp_type (str) – type of sigma point. Choose from merwe or julier

  • alpha (float) – scaling parameter for sigma points

  • beta (float) – scaling parameter for sigma points

  • kappa (float) – scaling parameter for sigma points

  • sqrt_func (function) – function to compute the square root of the covariance matrix

Methods

__init__(x_dict, cov, sp_type[, alpha, ...])

Initialize a sigma point object.

reconstruct(transformed_sigma_points)

Reconstruct the mean and covariance from transformed sigma points.

reconstruct(transformed_sigma_points)#

Reconstruct the mean and covariance from transformed sigma points.

Parameters:

transformed_sigma_points (np.ndarray) – transformed sigma points

Returns:

  • new_x (np.ndarray) – reconstructed mean

  • new_cov (np.ndarray) – reconstructed covariance