movav: Moving average

In l-ramirez-lopez/prospectr: Miscellaneous Functions for Processing and Sample Selection of Spectroscopic Data

Moving average

Description

A simple moving average of a matrix or vector using a convolution function written in C++/Rcpp for fast computing

Usage

movav(X, w)

Arguments

X	a numeric matrix or vector to process (optionally a data frame that can be coerced to a numerical matrix).
w	filter length.

Value

a matrix or vector with the filtered signal(s)

Author(s)

Antoine Stevens

See Also

savitzkyGolay, gapDer, binning, continuumRemoval

Examples

data(NIRsoil)
wav <- as.numeric(colnames(NIRsoil$spc))
# adding some noise
NIRsoil$spc_noise <- NIRsoil$spc + rnorm(length(NIRsoil$spc), 0, 0.001)
matplot(wav,
  t(NIRsoil$spc_noise[1:10, ]),
  type = "l",
  lty = 1,
  xlab = "Wavelength /nm",
  ylab = "Absorbance",
  col = "grey"
)

# window size of 11 bands
NIRsoil$spc_mov <- movav(NIRsoil$spc_noise, w = 15)
# smoothed data
matlines(as.numeric(colnames(NIRsoil$spc_mov)),
  t(NIRsoil$spc_mov[1:10, ]),
  type = "l",
  lty = 1
)

l-ramirez-lopez/prospectr documentation built on Feb. 18, 2024, 7:52 a.m.