Module Evaluation 2D

# VITESS Module Evaluation 2D (eval_elast2)

    The module eval_elast2 is supposed to be used for elastic
    scattering (e.g. powder diffraction, SANS).

    The diffractogram or spectra file will contain the neutron probabilities counted for each
    segment of the evaluation interval (with respect to the evaluation parameter
    of interest).

    The following information has to be given as an input:

    evaluation parameter: choose between scattering angle vs. wavelength and
      scattering angle vs. TOF

    spectra file: the name of the spectra file which will contain
      the evaluated data has to be given.

    number of bins in X and Y: number of bins determines the segmentation of the
      scattering angle and wavelength or TOF direction.
      It is therewiththe number of values written to the file.

    minimum, maximum: the bounds of the interval for the evaluation parameter.

    increase to next bin X and Y: for a logarithmic binning the percentage has to be given
      by which the upper limit of each bin exceeds its lower limit.
      If this value is set, the given 'number of bins' is ignored

    dead-spot: only needed if the direct beam points to the detector
       (as in the case of SANS).
       All neutrons with a scattering angle(2 theta) between 0 and dead-spot [deg]
       will therefore not be considered in the evaluation.

    probability weight: if one deactivates the probability weight each
       neutron is considered with the weight 1, otherwise (default)
       the attributed probabilities (due to the operations of the modules before)
       are considered.

    time of flight:  if the wavelength of the neutrons shall be
       determined by time of flight analysis (i.e. each wavelength is
       calculated from the flight path and the flight time)
       this option must be activated when using scattering angle vs. wavelength.

    flight path [cm]: length of total neutron flight path,
       needed only for time of flight analysis.

    time offset [ms]: global shift of the neutron time t  t-TimeOffset [ms],
       useful to shift the temporal reference point for the time of flight analysis

    begin, end of evaluation: the bounds of the time interval for the evaluation.
       Only neutrons arriving in that time interval are considered in the
       evaluation

    color, mincolor, maxcolor: either the exact color is needed for evaluation (0 is any) or
       the color has to be in the range between mincolor and maxcolor (-1 is any color range).

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