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50 lines
1.4 KiB
R
50 lines
1.4 KiB
R
% Generated by roxygen2: do not edit by hand
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% Please edit documentation in R/apply_pixel.R
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\name{apply_pixel}
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\alias{apply_pixel}
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\title{Apply a function over (multi-band) pixels}
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\usage{
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apply_pixel(x, ...)
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}
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\arguments{
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\item{x}{input data}
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\item{...}{additional arguments passed to method implementations}
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}
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\value{
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return value and type depend on the class of x
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}
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\description{
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This generic function applies a function on pixels of a data cube, an R array, or other classes if implemented.
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}
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\examples{
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# create image collection from example Landsat data only
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# if not already done in other examples
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if (!file.exists(file.path(tempdir(), "L8.db"))) {
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L8_files <- list.files(system.file("L8NY18", package = "gdalcubes"),
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".TIF", recursive = TRUE, full.names = TRUE)
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create_image_collection(L8_files, "L8_L1TP", file.path(tempdir(), "L8.db"), quiet = TRUE)
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}
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v = cube_view(extent=list(left=388941.2, right=766552.4,
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bottom=4345299, top=4744931, t0="2018-04", t1="2018-06"),
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srs="EPSG:32618", nx = 497, ny=526, dt="P1M")
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L8.col = image_collection(file.path(tempdir(), "L8.db"))
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apply_pixel(raster_cube(L8.col, v), "(B05-B04)/(B05+B04)", "NDVI")
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d <- c(4,16,128,128)
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x <- array(rnorm(prod(d)), d)
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y <- apply_pixel(x, function(v) {
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v[1] + v[2] + v[3] - v[4]
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})
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}
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\seealso{
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\code{\link{apply_pixel.cube}}
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\code{\link{apply_pixel.array}}
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}
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