Finds and imports spectra files from a folder. Currently works for reflectance files generated in Ocean Optics SpectraSuite (USB2000, USB4000 and Jaz spectrometers), CRAIC software (after exporting) and Avantes (before or after exporting).
Arguments
- where
Folder in which files are located (defaults to current working directory).
- ext
File extension to be searched for, without the "." (defaults to
txt
). You can also use a character vector to specify multiple file extensions.- lim
A vector with two numbers determining the wavelength limits to be considered (defaults to
c(300, 700)
).- decimal
Character to be used to identify decimal plates (defaults to
.
).- sep
Column delimiting characters to be considered in addition to the default (which are: tab, space, and ";")
- subdir
Should subdirectories within the
where
folder be included in the search? (defaults toFALSE
).- subdir.names
Should subdirectory path be included in the name of the spectra? (defaults to
FALSE
).- ignore.case
Should the extension search be case insensitive? (defaults to
TRUE
)
Value
A data frame, of class rspec
, containing individual imported
spectral files as columns.
Reflectance values are interpolated to the nearest wavelength integer.
Details
You can customise the type of parallel processing used by this function with
the future::plan()
function. This works on all operating systems, as well
as high performance computing (HPC) environment. Similarly, you can customise
the way progress is shown with the progressr::handlers()
functions
(progress bar, acoustic feedback, nothing, etc.)
References
Gruson H, White TE, Maia R (2019) lightr: import spectral data and metadata in R. Journal of Open Source Software, 4(43), 1857, doi:10.21105/joss.01857 .
See also
lightr::lr_get_spec()
for a more flexible version of this function
(e.g. uninterpolated wavelengths), and lightr::lr_get_metadata()
for the retrieval
and import of spectral metadata.
See https://docs.ropensci.org/lightr/ for the complete, and up-to-date, list
of supported file formats.
Examples
# Import and inspect example spectral data with a range of set to 400-700nm.
rspecdata <- getspec(system.file("testdata", package = "lightr"), ext = "ttt", lim = c(400, 700))
#> 2 files found; importing spectra:
head(rspecdata)
#> wl avantes_export avantes_export_long
#> 1 400 4.0899 5.639232
#> 2 401 3.9514 6.342615
#> 3 402 4.1269 6.147300
#> 4 403 4.2617 6.010692
#> 5 404 4.1683 6.333537
#> 6 405 4.0871 6.490569