cl_surface: Returns surfaces and P-function values

In jpgattuso/CoastalLight: Available Light on the Coastal Ocean [0-200m] Floor

Description

This function is the main function of the package. It operates on the three standard regions "NonPolar", "Arctic", and "Antarctic" or on a subregion (see user's guide and function cl_subregion())

Usage

cl_surface(region, month = 0, E = 1.6, type = "s", dir = ".")

Arguments

region	: [character] choose among : "NonPolar", "Arctic" and "Antarctic" or give the name of a subregion of one of these three regions. For example : suppose you have calculated the Pfunction of a subregion called "med" from the main region "NonPolar". You have downloaded a file called "NonPolar.med.Pfunctions.dat" (see function cl_subregion()). In this case pass "NonPolar.med".
month	: [integer] the month (-1, 0, 1-12); if -1 gives the values for global and all months; if 0 gives the global value; if 1 < month < 12 gives the values for the month;
E	: [numeric] mol.photons \; m^{-2} \; d^{-1}
type	: [character] choose among : "Sg" "s" "P" "E" (default "s")
dir	: [character] only used if region is not one of the three standard regions but a subregion; in this case, it is the path to the directory where is stored the Pfunction file (example : "NonPolar.med.Pfunctions.dat") of this subregion ( default = ".", that is the current directory )

Details

This function uses the Pfunction file :

• included in the package if region is "NonPolar" "Arctic" or "Antarctic"

• previously calculated and downloaded if region is the name of a subregion.

Value

if type == "Sg" [numeric] : an unique value (surface area of the region in km^{2})

if type == "s" [numeric vector] : surface areas in km^{2} receiving more than E mol.photons \; m^{-2} \; d^{-1}

if type == "P" [numeric array] : values of the P-function in % for the E values

if type == "E" [numeric vector] : discrete values of E used for tabulated P-functions

Examples

## surface of the "NonPolar" region
cl_surface("NonPolar", type = "Sg")

## global P-function
cl_surface("NonPolar", month = 0, E = c(0.01,0.02,0.05,0.1,0.2,0.5,1), type = "P")

## get E values in "Arctic" region then computes and plot global and monthly P-functions
region <- "Arctic"
E <- cl_surface(region, type = "E")
pc <- cl_surface(region, month = -1, E = E, type = "P")
matplot(E, pc, type = "l", log = "x", xlim = rev(range(E)),
        lty = 1:5, col = 1:6, lwd = 2, ylab = "%", main = region)
legend("topleft", legend = colnames(pc),
        lty = 1:5, col = 1:6, lwd = 2, bty = "n")

## example for a subregion
region <- "NonPolar.Gabes"
## for this example the directory where to find the P-function file
##   "NonPolar.Gabes.Pfunctions.dat" is in the package itself;
##   you can obtain your own P-function files and save them in
##   the directory of your choice - see function cl_subregion()
dir <- system.file("extdata", package = "CoastalLight")
E <- cl_surface(region, type = "E", dir = dir)
pc <- cl_surface(region, month = -1, E = E, type = "P", dir = dir)
matplot(E, pc, type = "l", log = "x", xlim = rev(range(E)),
        lty = 1:5, col = 1:6, lwd = 2, ylab = "%", main = region)
legend("topleft", legend = colnames(pc),
        lty = 1:5, col = 1:6, lwd = 2, bty = "n")

jpgattuso/CoastalLight documentation built on June 25, 2021, 5:34 p.m.