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Write ENVI spectral libraries

Source: R/readSLI.R
writeSLI.Rd

Writes binary ENVI spectral library files (sli) with accompanying header (.sli.hdr) files OR ASCII spectral library files in ENVI format.

Usage

writeSLI(
  x,
  path,
  wavl.units = "Micrometers",
  scaleF = 1,
  mode = "bin",
  endian = .Platform$endian
)

Arguments

x

data.frame with first column containing wavelengths and all other columns containing spectra.

path

path to spectral library file to be created.

wavl.units

wavelength units. Defaults to Micrometers. Nanometers is another typical option.

scaleF

optional reflectance scaling factor. Defaults to 1.

mode

character string specifying output file type. Must be one of "bin" for binary .sli files or "ASCII" for ASCII ENVI plot files.

endian

character. Optional. By default the endian is determined based on the platform, but can be forced manually by setting it to either "little" or "big".

Value

Does not return anything, write the SLI file directly to your drive for where your specified your path parameter

Details

ENVI spectral libraries with ending .sli are binary arrays with spectra saved in rows.

See also

readSLI

Examples


## Example data
sliFile <- system.file("external/vegSpec.sli", package="RStoolbox")
sliTmpFile <- paste0(tempdir(),"/vegetationSpectra.sli") 

## Read spectral library
sli <- readSLI(sliFile)
head(sli)
#>   wavelength veg_stressed   veg_vital
#> 1        350  0.008958003 0.008836994
#> 2        351  0.008910760 0.008909440
#> 3        352  0.008874181 0.008972186
#> 4        353  0.008847097 0.009025744
#> 5        354  0.008829174 0.009071405
#> 6        355  0.008819440 0.009109739
plot(sli[,1:2], col = "orange", type = "l")
lines(sli[,c(1,3)], col = "green")

 
## Write to binary spectral library
writeSLI(sli, path = sliTmpFile)