arrayspline: Applies a spline function to an array of values

In ilyamaclean/microclima: microclimate modelling with R

Applies a spline function to an array of values

Description

arrayspline is used to derive e.g. hourly climate data from e.g. daily values.

Usage

arrayspline(a, tme, nfact = 24, out = NA)

Arguments

a	a three-dimensional array (row, column, time)
tme	an object of class POSIXct of times for a. I.e. length(tme) = dim(a)[3]
nfact	indicates the time interval for which outputs are required. E.g to derive hourly from daily data nfact = 24, or derive six-hourly from daily data nfact = 4
out	an optional character vector indicating the time for which the output is required. Format must be as for tme.

Details

arrayspline uses the Forsythe, Malcolm and Moler method of splining, as specified by "fmm" in spline(). If a[i, j, ] is a vector of NAs, then tthe corresponding vector in the output array is also a vector of NAs. It is assumed that all spatial data within a have equivelent times. I.e. the time of both a[1, 1, 1] and a[1000, 1000, 1] is identical and equal to tme[1].

Value

If out is unspecified, a three dimensional array of size c(a[1], a[2], (length(tme) - 1) * nfact + 1) is returned. If out is specified, a three dimensional array of size c(a[1], a[2], length(out)) is returned.

Examples

library(raster)
tme <- as.POSIXct(c(0:364) * 24 * 3600, origin="2010-01-01", tz = "GMT")
h <- arrayspline(huss, tme, out = "2010-05-01 11:00")
plot(raster(h, template = dtm1km),
     main = "Specific humidity 2010-05-01 11:00")

ilyamaclean/microclima documentation built on Oct. 31, 2023, 11:41 p.m.