UKFE (version 1.0.2)

DDF: DDF results from a DDFImport object

Description

Extracts results from a data frame imported using the DDFImport function

Usage

DDF(x, duration, RP = 100)

Value

A DDF13 or DDF22 estimate of rainfall depth (mm)

Arguments

x

A data frame of DDF13 or DDF22 results imported using the DDFImport function

duration

the duration (hrs) for which a rainfall depth estimate is required

RP

the return period (years) for which a rainfall depth estimate is required

Author

Anthony Hammond

Details

The .xml files only provide a set number of durations and return periods for DDF13 and DDF22. This function optimises the GEV distribution on the results in order to interpolate across return periods. A linear interpolation is used between durations. The interpolation method may provide results that differ from the FEH webservice in the region of 0.1mm. The result is then rounded to an integer.

Examples

# Import DDF13 results from an NRFA Peak Flows XML file
if (FALSE) {
ddf13_4003 <- DDFImport("C:/Data/NRFAPeakFlow_v9/Suitable for QMED/04003.xml", DDFVersion = 13)
}

# Estimate the 20-year, 5-hour depth
if (FALSE) {
DDF(ddf13_4003, duration = 5, RP = 20)
}