# unit.hydrograph.storage.cascade: Unit hydrograph linear storage cascade In RHydro: Classes and methods for hydrological modelling and analysis

## Description

Compute the shape of a Unit hydrograph linear storage cascade with the given parameters and apply it to given rainfall series.

## Usage

 1 2 unit.hydrograph.storage.cascade(n, k, delta_t) apply_uhg(rainfall, uhg_params, delta_t)

## Arguments

 n number of linear storages [-] k recession constant (same unit as delta_t) delta_t time resolution of return vector [time]. rainfall vector of rainfall series in time resolution of delta_t. uhg_params vector with named components "n" and "k" (parameters of UHG) OR matrix with named columns "n", "k" and "a". In the latter case, a multiple UHG is applied with the weights in "a".

## Details

The resulting vector h would, in principle, be of infinite length because of the asymptotic behaviour of the storage outflow. For practical reasons, it is trimmed so that at least 99% of the volume is reproduced.

## Value

vector h with ordinates of unit hydrograph or modelled hydrograph, corresponding to temporal resolution of delta_t starting with t=0

Till Francke

## Examples

 1 2 3 4 5 6 7 8 9 10 #simple unit hydrograph ordinates delta_t = 0.5 uh = unit.hydrograph.storage.cascade(n=2, k=3, delta_t = delta_t) plot(seq(from=delta_t, by=delta_t, along.with=uh) , uh, type="l") #compute hydrograph from multiple UHGs: rainfall <- ,"P"] uhg_params=rbind( c(n=2, k=3, a=0.4), c(n=20, k=3, a=0.6)) #two-element unit hydrograph, weighted 40 and 60 %, resp. plot(apply_uhg(rainfall, uhg_params, delta_t), type="l")

RHydro documentation built on May 2, 2019, 6:24 p.m.