5.0 | 4 ratings Rate this file 15 downloads (last 30 days) File Size: 1.54 KB File ID: #12694

Memory mapping matrices

18 Oct 2006 (Updated 27 Nov 2006)

No BSD License

memory mapping and accessing matrices

File Information
Description	making and accessing files via memory mapping. very useful when working with a very large data sets/matrices. instead of loading the whole matrix , you can access just specific part of it. very efficient.
MATLAB release	MATLAB 7.3 (R2006b)
Other requirements	nonee
Zip File Content
Other Files	mem/MemMapBin.m, mem/WriteBinFile.m

Tags for This File
Everyone's Tags	cell arrays, memory mapping files pointers data, structures
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Comments and Ratings (4)
23 Oct 2006	ron ganor	An excellent way to implement the memory mapping capabilities of matlab. Very efficient, very well done. Maybe the data handling way of the future? ... Recomende
01 Feb 2007	Claudiu Giurumescu	It works in 7.1SP3 too. Updated both scripts a bit so that different data types are handled correctly. Definitely solves my memory problems. Great idea.
21 Mar 2007	Anton Sirota	Nice that you brought that up. memmapfile does make the binary file operations much less painful and more elegant. just wanted to comment: in my experience reading/writing (actually, both can be implemented with memmampfile) consecutive samples from/to binary file with memmapfile is not much different in terms of memory usage and speed from buffered fread/fwrite (with varying offset, skip, format) given that buffer size is chosen accordingly. It seems after all what matters is file caching by the OS. Also, so far even 64bit version of MATLAB under true 64bit Linux doesn't allow mapping more that 2^31-1, thus limiting you to 2GB file size, if you wanted to map it all.
28 Mar 2009	Tarik Akbudak	could you explain how to assign complex data types too?? because it is not allowed to assign complex numbers in matrices.

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Updates
27 Nov 2006	ta ta ..

Tag Activity for this File
Tag	Applied By	Date/Time
structures	David B. Omer	22 Oct 2008 08:44:24
cell arrays	David B. Omer	22 Oct 2008 08:44:24
memory mapping files pointers data	David B. Omer	22 Oct 2008 08:44:24

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