change_points

Calculates flow (Q) differences of consecutive time steps and
 discriminates between time steps with increasing (IC: \(Q_{ts1} &lt; Q_{ts2}\))
 and decreasing (DC: \(Q_{ts1} &gt; Q_{ts2}\)) flow. The differences are
 transformed to 1 or -1 if the number is positive or negative, respectively.
 Then the lengths of runs of equal values are computed to determine the
 change point indices in the input data frame. <code>NA</code> in Q values is
 replaced with 0 and treated as an equal trend.

internal

An important environmental impact on running water ecosystems
is caused by hydropeaking - the discontinuous release of turbine water
because of peaks of energy demand. An event-based algorithm is implemented
to detect flow fluctuations referring to increase events (IC) and decrease
events (DC). For each event, a set of parameters related to the fluctuation
intensity is calculated. The framework is introduced in Greimel et al. (2016)
"A method to detect and characterize sub-daily flow fluctuations"
<doi:10.1002/hyp.10773> and can be used to identify different fluctuation
types according to the potential source: e.g., sub-daily flow fluctuations
caused by hydropeaking, rainfall, or snow and glacier melt.
This is a companion to the package 'hydroroute', which is used to detect and
follow hydropower plant-specific hydropeaking waves at the sub-catchment
scale and to describe how hydropeaking flow parameters change along the
longitudinal flow path as proposed and validated in Greimel et al. (2022).

Bettina Gruen

hydropeak

Detect and Characterize Sub-Daily Flow Fluctuations

Bettina Grün

Julia Haider

Franz Greimel

change_points function

<dl><dt>x</dt>
<dd>Data frame (time series) of stage measurements. Data frame must contain
a date-time column (<code>Time</code>) and a flow rate column (<code>Q</code>) and must
be in a compatible format. (see <code>flow()</code>).</dd>
<dt>rownames</dt>
<dd>A logical. If <code>FALSE</code> (default) indices are used to
determine change points, otherwise row names. <code>rownames = TRUE</code> is
important for data with different IDs.</dd>
<dt>omit.constant</dt>
<dd>A logical. If <code>FALSE</code> (default) it does not return
events with constant measurements. Otherwise these events are included.</dd>
<dt>omit.na</dt>
<dd>A logical. If <code>FALSE</code> (default) it does not return missing
value events. Otherwise these events are included.</dd></dl>

Arguments

Change Points — change_points

<dl>

<dt>x</dt>
<dd>Data frame (time series) of stage measurements. Data frame must contain
a date-time column (<code>Time</code>) and a flow rate column (<code>Q</code>) and must
be in a compatible format. (see <code>flow()</code>).</dd>


<dt>rownames</dt>
<dd>A logical. If <code>FALSE</code> (default) indices are used to
determine change points, otherwise row names. <code>rownames = TRUE</code> is
important for data with different IDs.</dd>


<dt>omit.constant</dt>
<dd>A logical. If <code>FALSE</code> (default) it does not return
events with constant measurements. Otherwise these events are included.</dd>


<dt>omit.na</dt>
<dd>A logical. If <code>FALSE</code> (default) it does not return missing
value events. Otherwise these events are included.</dd>

</dl>

change_points: Change Points

Description

Usage

Value

Arguments