dfreproject.sip
===============

.. py:module:: dfreproject.sip


Functions
---------

.. autoapisummary::

   dfreproject.sip.get_sip_coeffs
   dfreproject.sip.apply_sip_distortion
   dfreproject.sip.apply_inverse_sip_distortion
   dfreproject.sip.iterative_inverse_sip


Module Contents
---------------

.. py:function:: get_sip_coeffs(wcs: astropy.wcs.WCS) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor]

   Extract SIP polynomial coefficients from a WCS object.

   Parameters:
   -----------
   wcs : astropy.wcs.WCS
       WCS object potentially containing SIP distortion

   Returns:
   --------
   dict:
       Dictionary containing SIP coefficient matrices A, B, AP, BP and orders


.. py:function:: apply_sip_distortion(u: torch.Tensor, v: torch.Tensor, sip_coeffs: Tuple, device: str = 'cpu')

   Apply SIP distortion to intermediate pixel coordinates.

   Parameters:
   -----------
   u, v : torch.Tensor
       Intermediate pixel coordinates (before distortion)
   sip_coeffs : Tuple[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor]
       SIP coefficient matrices
   device : torch.device, optional
       Device to place tensors on

   Returns:
   --------
   tuple:
       (u', v') distorted coordinates


.. py:function:: apply_inverse_sip_distortion(u: torch.Tensor, v: torch.Tensor, sip_coeffs: Tuple, device: str = 'cpu')

   Apply inverse SIP distortion to go from distorted to intermediate coordinates.

   Parameters:
   -----------
   u, v : torch.Tensor
       Distorted coordinates
   sip_coeffs : Tuple
       SIP coefficient matrices
   device : torch.device, optional
       Device to place tensors on

   Returns:
   --------
   tuple:
       (u', v') undistorted coordinates


.. py:function:: iterative_inverse_sip(u: torch.Tensor, v: torch.Tensor, sip_coeffs: Tuple, device: str = 'cpu', max_iter: int = 20, tol: float = 1e-08)

   Iteratively solve for undistorted coordinates when inverse SIP coefficients
   are not available.

   Parameters:
   -----------
   u, v : torch.Tensor
       Distorted coordinates
   sip_coeffs : Tuple
       SIP coefficient matrices
   device : torch.device, optional
       Device to place tensors on
   max_iter : int, optional
       Maximum number of iterations
   tol : float, optional
       Convergence tolerance

   Returns:
   --------
   tuple:
       (u', v') undistorted coordinates