This function returns the result of interpolating spectral data from the original set of wavelengths to a new one.
Usage
interpolate_wl(x, w.length.out, fill, length.out, ...)
# Default S3 method
interpolate_wl(x, w.length.out, fill, length.out, ...)
# S3 method for class 'generic_spct'
interpolate_wl(x, w.length.out = NULL, fill = NA, length.out = NULL, ...)
# S3 method for class 'generic_mspct'
interpolate_wl(
x,
w.length.out = NULL,
fill = NA,
length.out = NULL,
...,
.parallel = FALSE,
.paropts = NULL
)Arguments
- x
an R object
- w.length.out
numeric vector of wavelengths (nm)
- fill
a value to be assigned to out of range wavelengths
- length.out
numeric value
- ...
not used
- .parallel
if TRUE, apply function in parallel, using parallel backend provided by foreach
- .paropts
a list of additional options passed into the foreach function when parallel computation is enabled. This is important if (for example) your code relies on external data or packages: use the .export and .packages arguments to supply them so that all cluster nodes have the correct environment set up for computing.
Details
If length.out it is a numeric value, then gives the number of rows in the
output, if it is NULL, the values in the numeric vector w.length.out are used.
If both are not NULL then the range of w.length.out and length.out are
used to generate a vector of wavelength. A value of NULL for fill prevents
extrapolation.
Methods (by class)
interpolate_wl(default): Default for generic functioninterpolate_wl(generic_spct): Interpolate wavelength in an object of class "generic_spct" or derived.interpolate_wl(generic_mspct): Interpolate wavelength in an object of class "generic_mspct" or derived.
Note
The default fill = NA fills extrapolated values with NA. Giving NULL as
argument for fill deletes wavelengths outside the input data range from the
returned spectrum. A numerical value can be also be provided as fill. This function calls
interpolate_spectrum for each non-wavelength column in the input spectra object.
Examples
interpolate_wl(sun.spct, 400:500, NA)
#> Object: source_spct [101 x 3]
#> Wavelength range 400-500 nm, step 1 nm
#> Label: sunlight, simulated
#> Measured on 2010-06-22 09:51:00 UTC
#> Measured at 60.20911 N, 24.96474 E; Kumpula, Helsinki, FI
#> Variables:
#> w.length: Wavelength [nm]
#> s.e.irrad: Spectral energy irradiance [W m-2 nm-1]
#> s.q.irrad: Spectral photon irradiance [mol s-1 m-2 nm-1]
#> --
#> # A tibble: 101 × 3
#> w.length s.e.irrad s.q.irrad
#> <int> <dbl> <dbl>
#> 1 400 0.608 0.00000203
#> 2 401 0.626 0.00000210
#> 3 402 0.650 0.00000218
#> 4 403 0.621 0.00000209
#> 5 404 0.637 0.00000215
#> 6 405 0.626 0.00000212
#> 7 406 0.600 0.00000204
#> 8 407 0.595 0.00000202
#> 9 408 0.626 0.00000213
#> 10 409 0.662 0.00000226
#> # ℹ 91 more rows
interpolate_wl(sun.spct, 400:500, NULL)
#> Object: source_spct [101 x 3]
#> Wavelength range 400-500 nm, step 1 nm
#> Label: sunlight, simulated
#> Measured on 2010-06-22 09:51:00 UTC
#> Measured at 60.20911 N, 24.96474 E; Kumpula, Helsinki, FI
#> Variables:
#> w.length: Wavelength [nm]
#> s.e.irrad: Spectral energy irradiance [W m-2 nm-1]
#> s.q.irrad: Spectral photon irradiance [mol s-1 m-2 nm-1]
#> --
#> # A tibble: 101 × 3
#> w.length s.e.irrad s.q.irrad
#> <int> <dbl> <dbl>
#> 1 400 0.608 0.00000203
#> 2 401 0.626 0.00000210
#> 3 402 0.650 0.00000218
#> 4 403 0.621 0.00000209
#> 5 404 0.637 0.00000215
#> 6 405 0.626 0.00000212
#> 7 406 0.600 0.00000204
#> 8 407 0.595 0.00000202
#> 9 408 0.626 0.00000213
#> 10 409 0.662 0.00000226
#> # ℹ 91 more rows
interpolate_wl(sun.spct, seq(200, 1000, by=0.1), 0)
#> Object: source_spct [8,001 x 3]
#> Wavelength range 200-1000 nm, step 0.1 nm
#> Label: sunlight, simulated
#> Measured on 2010-06-22 09:51:00 UTC
#> Measured at 60.20911 N, 24.96474 E; Kumpula, Helsinki, FI
#> Variables:
#> w.length: Wavelength [nm]
#> s.e.irrad: Spectral energy irradiance [W m-2 nm-1]
#> s.q.irrad: Spectral photon irradiance [mol s-1 m-2 nm-1]
#> --
#> # A tibble: 8,001 × 3
#> w.length s.e.irrad s.q.irrad
#> <dbl> <dbl> <dbl>
#> 1 200 0 0
#> 2 200. 0 0
#> 3 200. 0 0
#> 4 200. 0 0
#> 5 200. 0 0
#> 6 200. 0 0
#> 7 201. 0 0
#> 8 201. 0 0
#> 9 201. 0 0
#> 10 201. 0 0
#> # ℹ 7,991 more rows
interpolate_wl(sun.spct, c(400,500), length.out=201)
#> Object: source_spct [201 x 3]
#> Wavelength range 400-500 nm, step 0.5 nm
#> Label: sunlight, simulated
#> Measured on 2010-06-22 09:51:00 UTC
#> Measured at 60.20911 N, 24.96474 E; Kumpula, Helsinki, FI
#> Variables:
#> w.length: Wavelength [nm]
#> s.e.irrad: Spectral energy irradiance [W m-2 nm-1]
#> s.q.irrad: Spectral photon irradiance [mol s-1 m-2 nm-1]
#> --
#> # A tibble: 201 × 3
#> w.length s.e.irrad s.q.irrad
#> <dbl> <dbl> <dbl>
#> 1 400 0.608 0.00000203
#> 2 400. 0.617 0.00000207
#> 3 401 0.626 0.00000210
#> 4 402. 0.638 0.00000214
#> 5 402 0.650 0.00000218
#> 6 402. 0.635 0.00000214
#> 7 403 0.621 0.00000209
#> 8 404. 0.629 0.00000212
#> 9 404 0.637 0.00000215
#> 10 404. 0.632 0.00000214
#> # ℹ 191 more rows