my.test1fun {RFlocalfdr}

my.test1fun

Description

tests the compliance of skew-normal distribution functions with the expectations of the package fitdistrplus

Usage

my.test1fun(fn, start.arg, fix.arg, dpqr)

Arguments

fn

• name of the function to be tested "dsn", "psn" or "qsn"

start.arg

• the starting arguments for fitting the density

fix.arg

• fixed arguments

dpqr

– are we testing the "d", "p" or "q" function? not needed as it can be inferred from the argument "fn"

Details

RFlocalfdr also uses wrappers around the funcions dsn, qsn and psn from the package "sn" https://cran.r-project.org/web/packages/sn/. This is due to the fact that fitdistrplus::fitdist(imp, "sn", start = list(xi = mean(imp)... returns warnings such as The dsn function should return a zero-length vector when input has length zero and not raise an error The psn function should have its first argument named: q as in base R These wrappers ensure conformity with the expectations of fitdistrplus::fitdist

Value

fits the Density function for the skew-normal (SN) distribution.

Examples

library(sn)
curve(sn::dsn(x,xi=0, omega=1, alpha=1, tau=0),xlim=c(-10,10),col="blue")
curve(sn::dsn(x,xi=0, omega=1, alpha=0.1, tau=0),xlim=c(-10,10),col="blue",add=TRUE)
curve(sn::dsn(x,xi=1, omega=2, alpha=2, tau=0),xlim=c(-10,20),col="blue",add=TRUE)
curve(sn::dsn(x,xi=3, omega=4, alpha=4, tau=0),xlim=c(-10,20),col="blue",add=TRUE)

curve(my.dsn(x),xlim=c(-10,10),col="red",add=TRUE)
curve(my.dsn(x,lambda=0.1),xlim=c(-10,10),col="red",add=TRUE)
curve(my.dsn(x,xi=1, omega=2, lambda=2),xlim=c(-10,20),col="red",add=TRUE)
curve(my.dsn(x,xi=3, omega=4, lambda=4),xlim=c(-10,20),col="red",add=TRUE)

#dsn, qsn and psn are wrappers around the provided functions provided by sn. This is done to
# overcome some checking done by fitdistrplus

library(sn)
getAnywhere("dsn")
RFlocalfdr::my.test1fun("sn::dsn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))
RFlocalfdr::my.test1fun("sn::psn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))
RFlocalfdr::my.test1fun("sn::qsn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))
#all return FALSE

detach("package:sn", unload=TRUE)
getAnywhere("dsn")
RFlocalfdr::my.test1fun("dsn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))#TRUE
RFlocalfdr::my.test1fun("psn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))#TRUE
RFlocalfdr::my.test1fun("qsn", list(xi = -Inf, omega =1, alpha=0 ), fix.arg = list(tau = 0))#TRUE