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numarray
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numarray provides support for the creation of arrays which are
mapped directly onto files with the numarray.memmap module.
Much of numarray's design, the ability to handle misaligned and
byteswapped arrays for instance, was motivated by the desire to create
arrays from portable files which contain binary array data. One
advantage of memory mapping is efficient random access to small
regions of a large file: only the region of the mapped file which is
actually used in array operations needs to be paged into system
memory; the rest of the file remains unread and unwritten.
numarray.memmap is pure Python and is layered on top of
Python's mmap module. The basic idea behind numarray's
memory mapping is to create a ``buffer'' referring to a region in a
mapped file and to use it as the data store for an array. The
numarray.memmap module contains two classes, one which
corresponds to an entire mapped file (Memmap) and one which
corresponds to a contiguous region within a file
(MemmapSlice). MemmapSlice objects have these
properties:
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numarray
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