prtPreProcHistEq   Histogram equalization pre-processing
 
    HISTEQ = prtPreProcHistEq creates a histogram equalization pre
    processing object. A prtPreProcHistEq object processes the input
    data
    so that the distribution of each feature is approximately uniform
    in the range [0,1].
 
    prtPreProcHistEq has the following properties:
 
    nSamples    - The number of samples to use when learning the
                histogtram of the training data.  The default is inf
                (which uses all the data), however for large data sets
                this can be slow.
 
    A prtPreProcHistEq object also inherits all properties and functions from
    the prtAction class
 
    Example:
 
    dataSet = prtDataGenIris;              % Load a data set
    dataSet = dataSet.retainFeatures(1:2); % Use only the first 2
                                           % Features
    histEq = prtPreProcHistEq;             % Create the
                                           % prtPreProcHistEq Object
 
    histEq = histEq.train(dataSet);        % Train the object
    dataSetNew = histEq.run(dataSet);      % Equalize the histogram
 
    % Plot
    subplot(2,1,1); plot(dataSet);
    title('Original Data');
    subplot(2,1,2); plot(dataSetNew);
    title('HistEq Data');