raster (version 2.8-19)

datasource: Are values in memory and/or on disk?

Description

These are helper functons for programmers and for debugging that provide information about whether a Raster object has associated values, and if these are in memory or on disk.

fromDisk is TRUE if the data source is a file on disk; and FALSE if the object only exists in memory.

inMemory is TRUE if all values are currently in memory (RAM); and FALSE if not (in which case they either are on disk, or there are no values).

hasValues is TRUE if the object has cell values.

Usage

fromDisk(x)
inMemory(x)
hasValues(x)

Arguments

x

Raster* object

Value

Logical value

Examples

# NOT RUN {
rs <- raster(system.file("external/test.grd", package="raster"))
inMemory(rs)
fromDisk(rs)
rs <- readAll(rs)
inMemory(rs)
fromDisk(rs)
rs <- rs + 1
inMemory(rs)
fromDisk(rs)
rs <- raster(rs)
inMemory(rs)
fromDisk(rs)
rs <- setValues(rs, 1:ncell(rs))
inMemory(rs)
fromDisk(rs)
rs <- writeRaster(rs, filename='test', overwrite=TRUE)
inMemory(rs)
fromDisk(rs)
# }