Function writing: Helper functions to use in new functions you develop
Description
low level functions for programmers
canProcessInMemory is typically used within functions. In the raster package this function is used to determine if the amount of memory needed for the function is available. If there is not enough memory available, the function returns FALSE, and the function that called it will write the results to a temporary file.
openConnection opens a file connection for reading, closeConnection removes it.
pbCreate creates a progress bar, pbStep sets the progress, and pbClose closes it.