slice_space

Extract a single time series (spatial slice) from a data cube

Description

Create a proxy data cube, which extracts a time series from a data cube defined by spatial coordinates or integer x and y indexes.

Usage

slice_space(cube, loc = NULL, i = NULL)

Arguments

Argument Description
cube source data cube
loc numeric length-two vector; spatial coordinates (x, y) of the time series, expressed in the coordinate reference system of the source data cube
i integer length-2 vector; indexes (x,y) of the time slice (zero-based)

Details

Either loc or i must be non-NULL. If both arguments are provided, integer indexes i are ignored.

Note

This function returns a proxy object, i.e., it will not start any computations besides deriving the shape of the result.

Examples

# create image collection from example Landsat data only 
# if not already done in other examples
if (!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) 
}
L8.col = image_collection(file.path(tempdir(), "L8.db"))
v = cube_view(extent=list(left=388941.2, right=766552.4, 
              bottom=4345299, top=4744931, t0="2018-01", t1="2018-12"),
              srs="EPSG:32618", nx = 497, ny=526, dt="P3M", aggregation = "median")
L8.cube = raster_cube(L8.col, v, mask=image_mask("BQA", bits=4, values=16))
L8.rgb = select_bands(L8.cube, c("B02", "B03", "B04"))
L8.ts = slice_space(L8.rgb, loc = c(5e05, 4400000))
L8.ts
A data cube proxy object

Dimensions:
               low             high count       pixel_size chunk_size
t       2018-01-01       2018-12-31     4              P3M          1
y 4690228.52091255 4690988.27756654     1 759.756653992459          1
x 499869.238631791  500629.01971831     1 759.781086519128          1

Bands:
  name offset scale nodata unit
1  B02      0     1    NaN     
2  B03      0     1    NaN     
3  B04      0     1    NaN     
plot(L8.ts, join.timeseries = TRUE)