Histogram.py
============
This module uses matplotlib to plot an histogram of a gaussian distribution and calculates the project n-sigma interval.

The data can either collected from the clipboard or from a text file. Use the following command line text to call
this module.

.. code-block:: text

    python -m PyLTSpice.Histogram [options] [data_file] TRACE

The help can be obtained by calling the script without arguments

.. code-block:: text

    Usage: Histogram.py [options] LOG_FILE TRACE

    Options:
      --version             show program's version number and exit
      -h, --help            show this help message and exit
      -s SIGMA, --sigma=SIGMA
                            Sigma to be used in the distribution fit. Default=3
      -n NBINS, --nbins=NBINS
                            Number of bins to be used in the histogram. Default=20
      -c FILTERS, --condition=FILTERS
                            Filter condition writen in python. More than one
                            expression can be added but each expression should be
                            preceded by -c. EXAMPLE: -c V(N001)>4 -c parameter==1
                            -c  I(V1)<0.5
      -f FORMAT, --format=FORMAT
                            Format string for the X axis. Example: -f %3.4f
      -t TITLE, --title=TITLE
                            Title to appear on the top of the histogram.
      -r RANGE, --range=RANGE
                            Range of the X axis to use for the histogram in the
                            form min:max. Example: -r -1:1
      -C, --clipboard       If the data from the clipboard is to be used.
      -i IMAGEFILE, --image=IMAGEFILE
                            Name of the image File. extension 'png'