prospectr: resample – R documentation

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resample

Resample spectral data

Description

Resample a data matrix or vector to new coordinates (e.g. band positions) using spline or linear interpolation. This function is a simple wrapper around approx and splinefun in base.

Usage

resample(X, wav, new.wav, interpol = "spline", ...)

Arguments

`X`	numeric matrix or vector to resample (optionally a data frame that can be coerced to a numerical matrix).
`wav`	a numeric vector giving the original band positions.
`new.wav`	a numeric vector giving the new band positions.
`interpol`	the interpolation method: 'linear' or 'spline' (default).
`...`	additional arguments to be passed to the `splinefun` function when `interpol = 'spline'`.

Value

a matrix or vector with resampled values.

Author(s)

Antoine Stevens and Leonardo Ramirez-Lopez

Examples

data(NIRsoil)
wav <- as.numeric(colnames(NIRsoil$spc))
# increase spectral resolution by 2
NIRsoil$spc_resampled <- resample(NIRsoil$spc, wav, seq(1100, 2498, 2))
dim(NIRsoil$spc)
dim(NIRsoil$spc_resampled)

prospectr

Miscellaneous Functions for Processing and Sample Selection of Spectroscopic Data

v0.2.1

MIT + file LICENSE

Authors

Antoine Stevens [aut, cre] (<https://orcid.org/0000-0002-1588-7519>), Leonardo Ramirez-Lopez [aut, cre] (<https://orcid.org/0000-0002-5369-5120>), Guillaume Hans [ctb] (<https://orcid.org/0000-0002-6503-5760>)

Initial release

2020-10-23