Random access on a huge file in haskell -

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what best way read huge file (around 1 tb) in haskell. file contains matrix of integer data. , may need (efficiently ) calculate correlation between different rows or between columns.

i have used pytables thinking of trying same in haskell. know haskell has hdf5 bindings there other options not aware of ?

you give mmap try. example, can map whole file bytestring:

import data.bytestring b import system.io.mmap  main =     bs <- mmapfilebytestring "mylargefile" nothing     let l = b.length bs     print l     -- print last 1024 bytes:     let bs2 = b.drop (l - 1024) bs     print (b.unpack bs2)

cutting piece out of fast - no data copied. can use whatever tool parse bytestrings.


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