calc_pielou_evenness

This function calculates Pielou's evenness index, a measure of the distribution of abundances across
molecular formulas. Evenness ranges from 0 (one molecular formula dominates) to 1 (all formulas are equally abundant).
Evenness is derived using the Shannon index:
$$E = \frac{H}{\log(S)}$$
where:<ul>
<li>$H$ is the Shannon diversity index.</li>
<li>$S$ is the number of unique molecular formulas.</li>
</ul>If there is only one molecular formula, evenness is defined as 1.

Provides tools for assigning molecular formulas from exact masses
obtained by ultrahigh-resolution mass spectrometry. The methodology follows
the workflow described in Leefmann et al. (2019) <doi:10.1002/rcm.8315>.
The package supports the inspection, filtering and visualization of
molecular formula data and includes utilities for calculating common
molecular parameters (e.g., double bond equivalents, DBE). A graphical
user interface is available via the 'shiny'-based 'ume' application.

Boris Koch

Ultrahigh-Resolution Mass Spectrometry Data Evaluation for
Complex Organic Matter

calc_pielou_evenness function

<dl><dt>mf</dt>
<dd>Character vector. A list of unique molecular formulas.</dd>
<dt>magnitude</dt>
<dd>Numeric vector. A list of respective intensities (abundances) for each molecular formula.
Must be non-negative and have the same length as <code>mf</code>.</dd></dl>

Arguments

This function calculates Pielou's evenness index, a measure of the distribution of abundances across
molecular formulas. Evenness ranges from 0 (one molecular formula dominates) to 1 (all formulas are equally abundant).
Evenness is derived using the Shannon index:
$$E = \frac{H}{\log(S)}$$
where:<ul>
<li>$H$ is the Shannon diversity index.</li>
<li>$S$ is the number of unique molecular formulas.</li>
</ul>

If there is only one molecular formula, evenness is defined as 1.

Calculate Pielou's Evenness — calc_pielou_evenness

<dl>

<dt>mf</dt>
<dd>Character vector. A list of unique molecular formulas.</dd>


<dt>magnitude</dt>
<dd>Numeric vector. A list of respective intensities (abundances) for each molecular formula.
Must be non-negative and have the same length as <code>mf</code>.</dd>

</dl>

calc_pielou_evenness: Calculate Pielou's Evenness

Description

Usage

Value

Arguments

Examples