hologradpy.fitting
==================

.. py:module:: hologradpy.fitting

.. autoapi-nested-parse::

   This module contains functions for curve fitting.



Classes
-------

.. autoapisummary::

   hologradpy.fitting.FitSine


Functions
---------

.. autoapisummary::

   hologradpy.fitting.tilt
   hologradpy.fitting.remove_tilt
   hologradpy.fitting.gaussian
   hologradpy.fitting.fit_gaussian


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

.. py:function:: tilt(xy, *args, mask=None)

   Fit function containing the first three Zernike polynomials of the form z = c0 + c1 * x + c2 * y + c3 * 2xy.

   :param xy: x, y coordinate vectors.
   :param args: Vector of length 4, containing Zernike coefficients.
   :return: First 3 Zernike polynomials.


.. py:function:: remove_tilt(img, mask=None)

   This function removes fits the first three Zernike polynomials (Piston and tilt) to an image and subtracts the
   fitted function from the original image.
   :param ndarray img: Input image.
   :param ndarray mask: Binary mask in which to remove tilt.
   :return: Image without tilt.


.. py:function:: gaussian(xy, *args)

   Gaussian fit function.

   :param xy: x, y coordinate vectors.
   :param args: Fitting parameters passed to patterns.gaussian.
   :return: Gaussian.


.. py:function:: fit_gaussian(img, dx=None, dy=None, sig_x=15, sig_y=15, a=None, c=0, blur_width=10, xy=None)

   Fits a 2D Gaussian to an image. The image s blurred using a Gaussian filer before fitting.

   :param img: Input image.
   :param dx: X-offset of Gaussian [px].
   :param dy: Y-offset of Gaussian [px].
   :param sig_x: X-width of Gaussian [px].
   :param sig_y: -width of Gaussian [px].
   :param a: Amplitude.
   :param c: Offset.
   :param blur_width: Width of Gaussian blurring kernel [px].
   :param xy: X, Y meshgrid. If not specified, pixel coordinates are used.
   :return: Fitting parameters, parameter errors.


.. py:class:: FitSine(fl, k, dx=None, dy=None)

   This class is used in the wavefront measurement to fit a 2D sine to the interference pattern on the camera. The
   distance between the sample and reference patch can be set by calling the method set_dx_dy.


   .. py:attribute:: fl


   .. py:attribute:: dx
      :value: None



   .. py:attribute:: dy
      :value: None



   .. py:attribute:: k


   .. py:method:: set_dx_dy(dx, dy)

      Method to set parameters dx and dy.
      :param dx: New dx.
      :param dy: New dy.



   .. py:method:: fit_sine(xy, *args)

      Method to perform 2D sine fit.
      :param xy: x, y coordinate vectors.
      :param args: Args passed to patterns.fringes_wavefront
      :return: 2D sine.