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simchirp
Compute and return simulated chirp function.
DESCRIPTION
This function computes and returns the coordinates of the
reflected simulated chirp function described in
Nason and Silverman, 1995.
This function is a useful test function for evaluating wavelet shrinkage
and time-scale analysis methodology as its frequency changes over time.
USAGE
simchirp(n=1024)
REQUIRED ARGUMENTS
None.
OPTIONAL ARGUMENTS
- n
- The number of ordinates from which to sample the chirp signal.
VALUE
A list with two components:
-
x
- a vector of length
n containing the ordered x ordinates of the
chirp from -1 to 1.
-
y
- a vector of length
n
containing the corresponding y ordinates of
the chirp.
SIDE EFFECTS
None
DETAILS
This function computes and returns the x and y coordinates of
the reflected chirp function described in
Nason and Silverman, 1995.
The formula for the reflected simulated chirp
is
The chirp returned is a discrete sample on n
equally spaced points between -1 and 1.
RELEASE
Version 3.5.3 Copyright Guy Nason 1994
EXAMPLES
#
# Generate the chirp
#
> test.data <- simchirp()$y
> tsplot(test.data)
