R: Read a data cube from an existing netCDF file

ncdf_cube {gdalcubes} | R Documentation

## Read a data cube from an existing netCDF file

### Description

Create a proxy data cube from a netCDF file that has been created using `write_ncdf`. This function does not read cubes from arbitrary netCDF files and can be used e.g., to load intermediate results and/or plotting existing netCDF cubes on disk without doing the data cube creation from image collections.

### Usage

    ncdf_cube(path, chunking = NULL, auto_unpack = TRUE)

### Arguments

`path` | path to an existing netCDF file
`chunking` | custom chunk sizes to read form the netCDF file; defaults to using chunk sizes from the netCDF file
`auto_unpack` | logical; automatically apply offset and scale when reading data values

### Value

a proxy data cube object

### 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="2018-04", t1="2018-06"),
                  srs="EPSG:32618", nx = 497, ny=526, dt="P1M")

    ncfile = write_ncdf(select_bands(raster_cube(L8.col, v), c("B02", "B03", "B04")))
    ncdf_cube(ncfile)

[Package gdalcubes version 0.6.0 Index]