lmomco (version 2.4.14)

vec2lmom: Convert a Vector of L-moments to a L-moment Object

Description

This function converts a vector of L-moments to a L-moment object of lmomco. The object is an R list. This function is intended to facilitate the use of L-moments (and TL-moments) that the user might have from other sources. L-moments and L-moment ratios of arbitrary length are supported.

Because in typical practice, the $k\ge 3$ order L-moments are dimensionless ratios (${\tau }_3$, ${\tau }_4$, and ${\tau }_5$), this function computes ${\lambda }_3$, ${\lambda }_4$, ${\lambda }_5$ from ${\lambda }_2$ from the ratios. However, typical practice is not set on the use of ${\lambda }_2$ or $\tau$ as measure of dispersion. Therefore, this function takes an lscale optional logical (TRUE|FALSE) argument---if ${\lambda }_2$ is provided and lscale=TRUE, then $\tau$ is computed by the function and if $\tau$ is provided, then ${\lambda }_2$ is computed by the function.

Usage

vec2lmom(vec, lscale=TRUE,
         trim=NULL, leftrim=NULL, rightrim=NULL, checklmom=TRUE)

Value

An R

list is returned.

Arguments

vec

A vector of L-moment values in ${\lambda }_1$, ${\lambda }_2$ or $\tau$, ${\tau }_3$, ${\tau }_4$, and ${\tau }_5$ order.

lscale

A logical switch on the type of the second value of first argument. L-scale (${\lambda }_2$) or LCV ($\tau$). Default is TRUE, the second value in the first argument is ${\lambda }_2$.

trim

Level of symmetrical trimming, which should equal NULL if asymmetrical trimming is used.

leftrim

Level of trimming of the left-tail of the sample, which will equal NULL even if trim = 1 if the trimming is symmetrical.

rightrim

Level of trimming of the right-tail of the sample, which will equal NULL even if trim = 1 if the trimming is symmetrical.

checklmom

Should the lmom be checked for validity using the are.lmom.valid function. Normally this should be left as the default unless TL-moments are being constructed in lieu of using vec2TLmom.

Author

W.H. Asquith

See Also

lmoms, vec2pwm

Examples

lmr <- vec2lmom(c(12,0.6,0.34,0.20,0.05),lscale=FALSE)