recessionplot | R Documentation |
Helps to define the peak level of a low flow object and visualises recession periods.
recessionplot(lfobj, peaklevel = 0.95, plot = TRUE, peakreturn = FALSE, thresplot = TRUE, threscol = "blue", threshold = 70, thresbreaks = c("fixed","monthly","seasonal"), thresbreakdays = c("01/06","01/10"), recessionperiod = TRUE, recessioncol = "darkblue", seglength = 7, ...)
lfobj |
A object of class |
peaklevel |
A level between 0 and 1 or a logical vector, see details. |
plot |
Should a plot be made |
peakreturn |
Should a logical with rain peaks be returned |
thresplot |
Should the threshold be plotted |
threscol |
Colour of threshold in plot |
threshold |
Threshold level (70 refers to Q70) |
thresbreaks |
"fixed" uses a fixed threshold level, "monthly"
calculates the threshold for every month separately, "seasonal"
calculates thresholds for every season defined using
|
thresbreakdays |
Needed if |
recessionperiod |
Should recession periods be marked |
recessioncol |
Colour of recession period marks |
seglength |
The minimum number of days to be marked as recession period |
... |
Further arguments handed to |
.
For recession analysis it is necessary to define flood discharge peaks
in the hydrograph. The peak level defines a day to be a
discharge peak, if peaklevel * flow > flow[day before]
and
peaklevel * flow > flow[day after]
.
This function can be used to check different values of the peak level.
If 'peakreturn = TRUE'
: A logical vector giving rain peaks as TRUE
Daniel Koffler and Gregor Laaha
Gustard, A. & Demuth, S. (2009) (Eds) Manual on Low-flow Estimation and Prediction. Operational Hydrology Report No. 50, WNO-No. 1029, 136p.
recession
data(ngaruroro) # To few points identified as peak flood discharge recessionplot(ngaruroro, peaklevel = .5, start = 1991, end = 1991) # To many recessionplot(ngaruroro, peaklevel = .999, start = 1991, end = 1991) # Good choice? recessionplot(ngaruroro, peaklevel = .92, start = 1991, end = 1991) # Getting peakdays for 1991 peak <- recessionplot(ngaruroro, peaklevel = .92, plot = FALSE, peakreturn = TRUE) rain1991 <- subset(ngaruroro, subset = (hyear == 1991) & peak, select = c(day, month, year))
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.