## The module "frequency2index" of the Mastrave modelling library

Daniele de Rigo

The file frequency2index.m is part of Mastrave.

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#### Function declaration

idx = frequency2index( frequency_vals )



#### Description

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
observations.



#### 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

Keywords:
data-transformation, frequency, position

Version: 0.2.1

#### Support

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