This generic function applies a function on pixels of a data cube, an R array, or other classes if implemented.
Usage
apply_pixel(x, ...)
Arguments
Argument
Description
x
input data
…
additional arguments passed to method implementations
Value
return value and type depend on the class of x
Examples
# create image collection from example Landsat data only # if not already done in other examplesif (!file.exists(file.path(tempdir(), "L8.db"))) { L8_files <-list.files(system.file("L8NY18", package ="gdalcubes"),".TIF", recursive =TRUE, full.names =TRUE)create_image_collection(L8_files, "L8_L1TP", file.path(tempdir(), "L8.db"), quiet =TRUE) }v =cube_view(extent=list(left=388941.2, right=766552.4, bottom=4345299, top=4744931, t0="2018-04", t1="2018-06"),srs="EPSG:32618", nx =497, ny=526, dt="P1M")L8.col =image_collection(file.path(tempdir(), "L8.db"))apply_pixel(raster_cube(L8.col, v), "(B05-B04)/(B05+B04)", "NDVI")
A data cube proxy object
Dimensions:
low high count pixel_size chunk_size
t 2018-04-01 2018-06-30 3 P1M 1
y 4345299 4744931 526 759.756653992395 384
x 388941.2 766552.4 497 759.781086519115 384
Bands:
name offset scale nodata unit
1 NDVI 0 1 NaN
# apply_pixelApply a function over (multi-band) pixels```{r include=FALSE}library(gdalcubes)```## DescriptionThis generic function applies a function on pixels of a data cube, an R array, or other classes if implemented.## Usage```rapply_pixel(x, ...)```## Arguments| Argument | Description ||:------------|:----------------------------------|| x | input data || ... | additional arguments passed to method implementations |## Valuereturn value and type depend on the class of x## Examples```{r}# create image collection from example Landsat data only # if not already done in other examplesif (!file.exists(file.path(tempdir(), "L8.db"))) { L8_files <-list.files(system.file("L8NY18", package ="gdalcubes"),".TIF", recursive =TRUE, full.names =TRUE)create_image_collection(L8_files, "L8_L1TP", file.path(tempdir(), "L8.db"), quiet =TRUE) }v =cube_view(extent=list(left=388941.2, right=766552.4, bottom=4345299, top=4744931, t0="2018-04", t1="2018-06"),srs="EPSG:32618", nx =497, ny=526, dt="P1M")L8.col =image_collection(file.path(tempdir(), "L8.db"))apply_pixel(raster_cube(L8.col, v), "(B05-B04)/(B05+B04)", "NDVI") d <-c(4,16,128,128)x <-array(rnorm(prod(d)), d)y <-apply_pixel(x, function(v) { v[1] + v[2] + v[3] - v[4]})```## See Also[`apply_pixel.cube`](apply_pixel.cube.Rmd)[`apply_pixel.array`](apply_pixel.array.Rmd)