idst {gsignal}

Inverse Discrete Sine Transform

Description

Compute the inverse discrete sine transform of a signal.

Usage

idst(x, n = NROW(x))

Arguments

x

input discrete cosine transform, specified as a numeric vector or matrix. In case of a vector it represents a single signal; in case of a matrix each column is a signal.

n

transform length, specified as a positive integer scalar. Default: NROW(x).

Details

The discrete sine transform (DST) is closely related to the discrete Fourier transform. but using a purely real matrix. It is equivalent to the imaginary parts of a DFT of roughly twice the length.

Value

Inverse discrete sine transform, returned as a vector or matrix.

Author(s)

Paul Kienzle, [e-mail].
Conversion to R by Geert van Boxtel, [e-mail].

See Also

dst

Examples

x <- seq_len(100) + 50 * cos(seq_len(100) * 2 * pi / 40)
X <- dst(x)
xx <- idst(X)
all.equal(x, xx)