R: Extract a single time slice from a data cube

slice_time {gdalcubes} | R Documentation

## Extract a single time slice from a data cube

### Description

Create a proxy data cube, which extracts a time slice from a data cube defined by label (datetime string) or integer index.

### Usage

    slice_time(cube, datetime = NULL, it = NULL)

### Arguments

`cube` | source data cube
`datetime` | character; datetime string of the time slice
`it` | integer; index of the time slice (zero-based)

### Details

Either `datetime` or `it` must be non-NULL. If both arguments are provided, the integer index `it` is 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"))
    }
    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="P1M", 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.slice = slice_time(L8.rgb, "2018-03")
    L8.slice

    plot(L8.slice, rgb=3:1, zlim=c(5000,12000))

[Package gdalcubes version 0.6.0 Index]