The module "frequency2index" of the Mastrave modelling library


Daniele de Rigo


Copyright and license notice of the function frequency2index



Copyright © 2007,2008,2009,2010,2011,2014 Daniele de Rigo

The file frequency2index.m is part of Mastrave.

Mastrave is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

Mastrave is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

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Function declaration



idx = frequency2index( frequency_vals )




Module supporting the expansion of an array of frequencies frequency_vals into an array where the position of each element in frequency_vals is repeated according to the frequency.

Input arguments



 frequency_vals      ::numel::
                     Array counting the positive occurrences (presences).
                     For each element of the array, the local cumulated 
                     amount of presences is provided. An element's value of
                     zero is interpreted as an absence of positive

Example of usage



  n_elems = [2 0 3 4 0 0 5 3 ]
  pos     = frequency2index( n_elems )'

  % Dealing with first elements with frequency zero
  n_elems = [0 0 2 0 3 4 0 0 5 3 ]
  pos     = frequency2index( n_elems )'

  % Dealing with last elements with frequency zero
  n_elems = [2 0 3 4 0 0 5 3 0 0]
  pos     = frequency2index( n_elems )'

See also:
   mat2groups, frequency_resampling

   data-transformation, frequency, position

Version: 0.2.1




The Mastrave modelling library is committed to provide reusable and general - but also robust and scalable - modules for research modellers dealing with computational science.  You can help the Mastrave project by providing feedbacks on unexpected behaviours of this module.  Despite all efforts, all of us - either developers or users - (should) know that errors are unavoidable.  However, the free software paradigm successfully highlights that scientific knowledge freedom also implies an impressive opportunity for collectively evolve the tools and ideas upon which our daily work is based.  Reporting a problem that you found using Mastrave may help the developer team to find a possible bug.  Please, be aware that Mastrave is entirely based on voluntary efforts: in order for your help to be as effective as possible, please read carefully the section on reporting problems.  Thank you for your collaboration.

Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Daniele de Rigo

This page is licensed under a Creative Commons Attribution-NoDerivs 3.0 Italy License.

This document is also part of the book:
de Rigo, D. (2012). Semantic Array Programming with Mastrave - Introduction to Semantic Computational Modelling.

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