downsample function

Decrease sample rate

Downsample a signal by an integer factor.

downsample(x, n, phase = 0)

Arguments

• x: input data, 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: downsampling factor, specified as a positive integer.
• phase: offset, specified as a positive integer from 0 to n - 1. Default: 0.

Returns

Downsampled signal, returned as a vector or matrix.

Details

For most signals you will want to use decimate instead since it prefilters the high frequency components of the signal and avoids aliasing effects.

Examples

x <- seq_len(10)
xd <- downsample(x, 3)     # returns 1  4  7 10
xd <- downsample(x, 3, 2)  # returns 3 6 9

x <- matrix(seq_len(12), 4, 3, byrow = TRUE)
xd <- downsample(x, 3)

See Also

decimate, resample

Author(s)

Paul Kienzle, pkienzle@users.sf.net .

Conversion to R by Geert van Boxtel, G.J.M.vanBoxtel@gmail.com .