pysiral.retracker.tfmra
=======================

.. py:module:: pysiral.retracker.tfmra


Attributes
----------

.. autoapisummary::

   pysiral.retracker.tfmra.__author__
   pysiral.retracker.tfmra.CYTFMRA_OK


Classes
-------

.. autoapisummary::

   pysiral.retracker.tfmra.cTFMRA
   pysiral.retracker.tfmra.TFMRAMultiThresholdFreeboards


Functions
---------

.. autoapisummary::

   pysiral.retracker.tfmra.bnsmooth


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

.. py:data:: __author__
   :value: 'Stefan Hendricks <stefan.hendricks@awi.de>'


.. py:data:: CYTFMRA_OK
   :value: True


.. py:class:: cTFMRA

   Bases: :py:obj:`pysiral.retracker.BaseRetracker`


   The default TFMRA retracker implementation using cythonized
   functions for numerical perfomrance


   .. py:attribute:: DOCSTR
      :value: 'Threshold first maximum retracker (TFMRA)'



   .. py:method:: set_default_options(specified_options=None)

      Set the default options for the cTFMRA retracker. This can be modified
      by the specified_options keyword that will overwrite the values in the
      default options dictionary
      :param specified_options: (dict or dict-like) specific options
      :return:



   .. py:property:: default_options_dict


   .. py:method:: create_retracker_properties(n_records)

      Mandatory method, but unused
      :param n_records:
      :return:



   .. py:method:: l2_retrack(rng, wfm, indices, radar_mode, is_valid)

       API Calling method for retrackers.
      :param rng: (np.array, dim:(n_records, n_bins)
      :param wfm:
      :param indices:
      :param radar_mode:
      :param is_valid:
      :return:



   .. py:method:: get_tfmra_threshold(indices)

      Compute the TFMRA threshold for each waveform with several options.
      :param indices: A list of array indices for which to compute thresholds (e.g. for sea ice waveforms)
      :return: An array of thresholds with the dimensions of the l2 data object, but only values for <indices>



   .. py:method:: get_preprocessed_wfm(rng, wfm, radar_mode, is_valid)

      Returns the intermediate product (oversampled range bins,
      oversampled and filtered waveforms, indices of first maxima
      and peak power norm for custom applications



   .. py:method:: get_thresholds_distance(rng, wfm, fmi, t0, t1, return_all_values=False)

      Return the distance between two thresholds t0 < t1



   .. py:method:: get_filtered_wfm(rng, wfm, oversampling_factor, window_size)
      :staticmethod:


      Return a filtered version of the waveform. This process inclused
      oversampling, smoothing and normalization to the first maximum power.
      :param rng: (np.array, dim:n_records) window delay for each range bin
      :param wfm: (np.array, dim:n_records) the power for each range bin with
          sensor dependent units
      :param oversampling_factor: (int) The waveform oversamling factor
      :param window_size: (int) The filter size of the box filter
      :return:



   .. py:method:: get_first_maximum_index(wfm, peak_minimum_power, first_valid_idx=0)
      :staticmethod:


      Return the index of the first peak (first maximum) on the leading edge
      before the absolute power maximum. The first peak is only valid if
      its power exceeds a certain threshold
      :param wfm: (np.array, dim=(n_range_bins)): Normalied waveform power
      :param peak_minimum_power: (float) threshold for normalized power that
          a peak must surpass to be regarded as a first maximum candidate
      :param first_valid_idx: (int):
      :return:



   .. py:method:: get_threshold_range(rng: numpy.ndarray, wfm: numpy.ndarray, first_maximum_index: int, threshold: float, first_valid_idx: int = 0) -> Tuple[float, float, int]
      :staticmethod:


      Return the range value and the power of the retrack point at
      a given threshold of the firsts maximum power

      :param rng: (np.array, dim=(n_range_bins) Window delay in meters
      :param wfm: (np.array, dim=(n_range_bins) Waveform power in normalized units
      :param first_maximum_index: (int) Index of first maximum
      :param threshold: (float) Power threshold
      :param first_valid_idx: (int) First valid index for first maximum / leading edge

      :return: tfmra range (float), tfmra power (float)



.. py:class:: TFMRAMultiThresholdFreeboards(*args, **kwargs)

   Bases: :py:obj:`pysiral.l2proc.procsteps.Level2ProcessorStep`


   Level-2 processor step to compute elevations from a range of TFMRA thresholds.
   NOTE: Computational expensive, should be handled with care


   .. py:method:: execute_procstep(l1b, l2)

      Computes the elevation of a range of defined of TFMRA retrackers thresholds to all
      lead or ice elevations.
      :param l1b:
      :param l2:
      :return: error_status_flag



   .. py:property:: l2_input_vars


   .. py:property:: l2_output_vars


   .. py:property:: auxid_fmt


   .. py:property:: error_bit


.. py:function:: bnsmooth(x, window)

   Bottleneck implementation of the IDL SMOOTH function