arrayfrombuffer allows a programmer to use Numerical Python arrays whose
contents are stored in buffer objects, including memory-mapped files. Loading
an array from a file is easy, requiring only a module import and a single
function call. Loading the array is quick because it doesn't require any
copying from one part of memory to another. Arrays created with arrayfrombuffer
are also highly memory-efficient, since only the array data that you are
currently using gets loaded into memory. When an array is modified, only the
modified parts get written back out to disk. These arrays can also be bigger
than physical memory.
