IDFcurve {LPM}

Intensity duration frequency curve

Description

Estimate IDF curve fitting a [mm/h], m ,n, b[h] parameters

Usage

IDFcurve(rain, g, s, tc, stvalue1 = 1, stvalue2 = fre, fre, Tr = 200,
                      MP=F, Trplot=F)

Arguments

rain

Observed Univariate rainfall series non cumulative

g

Maximum bound for cumulative series. For daily series g = 7 is recommended, for hourly series g=24 is racommended

s

Threshold for defining "event". If "10", only h > = 10 mm values are considered

tc

Time of concentration of Basin [h]

stvalue1, stvalue2

Starting values of estimation algorithm. Deault stvalue1=1, stvalue2=fre

fre

Series frequency [h]. For daily series fre=24, for hourly series fre=1

Tr

Return period [y]. Default Tr=200

MP

logical: TRUE for 3 parameters formula i=a/(b+t)^m , FALSE for 2 parameters formula i=a*t^(n-1), Default MP=False

Trplot

logical: TRUE for plotting Tr values of a(Tr) parameter. Default Trplot=False

Details

Estimate parameters of Intensity Duration Frequency curves

Value

par

List of estimated parameters: a(tr), m, b, h(t) [mm], i(t) [mm/h], Offset of least squares optimizer

Curve

IDF curve Scattered point matrix [mm/h]

Note

a(tr) is defined by Gumbel distribution.

Author(s)

Corrado Tallerini

See Also

IDFcurve2

Examples

##    data(hourly.rainfall.series)
##    res = IDFcurve(hourly.rainfall.series ,24, 15, 1, fre=1, Tr=200, MP=F)
## --> 2 parameters IDF curve estimation of a hourly rainfall series applying
## --> a Threshold "15 mm"  and Time of concentration t=1 h
##    res = IDFcurve(hourly.rainfall.series ,24, 15, 1, fre=1, Tr=200, MP=T)
## --> 3 parameters IDF curve estimation of a hourly rainfall series applying
## --> a Threshold "15 mm"  and Time of concentration t=1 h
## --> It's obvious the best performance of the 3 parameters formula