regsamlmu {lmomRFA} | R Documentation |
Computes the “unbiased” sample L-moments and L-moment ratios of multiple sets of data stored in a list or matrix. Following the paradigm of regional frequency analysis, we regard the data sets as coming from different measurement sites.
regsamlmu(x, nmom = 5, sort.data = TRUE, lcv = TRUE)
x |
A list of numeric vectors, or a numeric matrix. |
nmom |
Number of L-moments to be found. |
sort.data |
Whether each data set should be sorted. |
lcv |
If TRUE , the second L-moment will be expressed
as a fraction of the mean, i.e. the computed value will be
the sample L-CV t=l_2/l_1.
If FALSE , the second L-moment will simply be
the sample L-scale value l_2. |
Sample L-moments are computed for each data set.
The calculations use samlmu
internally.
If x
is a list, each list element contains data for one site
and the names of the list elements are the site names.
If x
is a matrix, each column contains data for one site
and the column names are the site names.
A data frame with columns "name"
and "n"
,
containing respectively the site names and the
number of non-missing data values at each site,
and further columns containing the L-moments and L-moment ratios,
in the order l_1, t (or l_2),
t_3, t_4, etc.
The default parameter values are chosen to be convenient
for the regional frequency analysis methods described by
Hosking and Wallis (1997).
Note that the number of L-moments and the choice
of whether to return L-CV or L-scale
are different from the defaults for samlmu
.
J. R. M. Hosking hosking@watson.ibm.com
Hosking, J. R. M., and Wallis, J. R. (1997). Regional frequency analysis: an approach based on L-moments. Cambridge University Press.
data(Maxwind) # a list regsamlmu(Maxwind) data(airquality) # a data frame regsamlmu(airquality[1:4])