ch_fdcurve {CSHShydRology} | R Documentation |
A flow duration curve is a plot of flow magnitude against exceedance probability. The plot may contain the Gustard Curves (default) or they can be omitted. The default is for curves to be plotted against probability, but an option is to plot against the normalized exceedance probability. In that case, the x axis represents a normal distribution.
ch_fdcurve(DF, normal = FALSE, gust = TRUE, metadata = NULL)
DF |
a dataframe of daily flows from |
normal |
If |
gust |
If |
metadata |
dataframe of metadata, defaults to HYDAT_list. |
Create a Flow Duration Curve based upon Observations.
Plots the flow duration curve and returns a data frame containing:
exceedance probability |
probability |
flow |
d=flow values |
Paul Whitfield
Gustard, A., A. Bullock, and J.M. Dixon. 1992. Low flow estimation in the United Kingdom. Institute of Hydrology, 292. Wallingford: Institute of Hydrology.
Vogel, R.M., and N.M. Fennessy. 1994. Flow-duration curves. I: New Interpretation and confidence intervals. Journal of Water Resources Planning and Management ASCE 120:485-504.
Vogel, R.M., and N.M. Fennessy. 1995. Flow duration curves II: A review of applications in water resources planning. Water Resources Bulletin 31:1030-9.
data(HYDAT_list)
data(CAN05AA008)
# plot with Gustard 1992 curves
test <- ch_fdcurve(CAN05AA008, normal = FALSE, gust = TRUE)
# plot with normalized exceedance probability
test <- ch_fdcurve(CAN05AA008, normal = TRUE, gust = FALSE)