psd (version 2.1.2)

tapers-refinement: Taper constraints using simple derivatives

Description

Taper constraints using simple derivatives

Usage

ctap_simple(tapvec, ...)
# S3 method for tapers
ctap_simple(tapvec, ...)
# S3 method for default
ctap_simple(tapvec, maxslope = 1L, ...)

Arguments

tapvec

integer or 'tapers' object; the number of tapers at each frequency

...

optional arguments

maxslope

integer; constrain based on this maximum first difference

Author

A.J. Barbour

See Also

constrain_tapers, ctap_loess

Examples

# generate some random taper series and constrain them based on slopes
set.seed(1237)
n <- 11
x <- seq_len(n)
xn <- round(runif(n,1,n))

xnf <- ctap_simple(xn, 0) # flattens out
xnc <- ctap_simple(xn, 1) # no change, already only slopes = 1
try(all.equal(xnc, xn))
xnc2 <- ctap_simple(xn, 2) # slopes = 2 only

plot(xn, type='b', pch=16, ylim=c(0,12))
grid()
abline(a=0,b=1, col='red', lty=3); abline(a=0,b=2, col='blue', lty=3)
lines(xnf, type='b', col='green')
lines(xnc, type='b', col='red')
lines(xnc2, type='b', col='blue')
lines(0.2+as.vector(psd::ctap_simple(psd::as.tapers(xn))), type='b', pch=".", col='salmon')

# more examples: