sdf: Smooth Discounted Flow

In adc: Calculate Antecedent Discharge Conditions

Smooth Discounted Flow

Description

Applies exponential smoothing to discharge data.

Usage

sdf(discharge, delta = 0.95)

Arguments

discharge	vector of discharge data (numeric).
delta	the discount factor which can be any value between (0,1), defaults to 0.95. As delta approaches one, the average discounted flow approaches mean flow. Small values of delta return values closer to the current daily flow.

Details

The smooth discounted flow (SDF) was proposed by Kuhnert et al. (2012). The premise of SDF is to incorporate the influence of historical flows on flux:

SDF(δ) = dκ_{i-1} + (1-δ)\hat{q}_{i-1},

and

κ_{i} = ∑_{m=1}^{i}\hat{q}_m,

for discount factor δ, where κ_{i} represents cumulative flow up to the ith day.

Value

vector of values the same length as discharge.

References

Kuhnert, Petra M., Brent L. Henderson, Stephen E. Lewis, Zoe T. Bainbridge, Scott N. Wilkinson, and Jon E. Brodie. 2012. “Quantifying Total Suspended Sediment Export from the Burdekin River Catchment Using the Loads Regression Estimator Tool” Water Resources Research 48 (4). doi: 10.1029/2011WR011080.

Examples

# Standard use case
ma <- sdf(lavaca$Flow, delta=0.95)
head(ma)

adc documentation built on March 7, 2023, 6:40 p.m.