Finding size of Variable
Ayushi Dalmia
ayushidalmia2604 at gmail.com
Wed Feb 5 00:00:31 EST 2014
On Tuesday, February 4, 2014 7:36:48 PM UTC+5:30, Dennis Lee Bieber wrote:
> On Tue, 4 Feb 2014 05:19:48 -0800 (PST), Ayushi Dalmia
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> <ayushidalmia2604 at gmail.com> declaimed the following:
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> >I need to chunk out the outputs otherwise it will give Memory Error. I need to do some postprocessing on the data read from the file too. If I donot stop before memory error, I won't be able to perform any more operations on it.
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> 10 200MB files is only 2GB... Most any 64-bit processor these days can
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> handle that. Even some 32-bit systems could handle it (WinXP booted with
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> the server option gives 3GB to user processes -- if the 4GB was installed
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> in the machine).
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> However, you speak of an n-way merge. The traditional merge operation
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> only reads one record from each file at a time, examines them for "first",
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> writes that "first", reads next record from the file "first" came from, and
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> then reassesses the set.
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> You mention needed to chunk the data -- that implies performing a merge
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> sort in which you read a few records from each file into memory, sort them,
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> and right them out to newFile1; then read the same number of records from
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> each file, sort, and write them to newFile2, up to however many files you
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> intend to work with -- at that point you go back and append the next chunk
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> to newFile1. When done, each file contains chunks of n*r records. You now
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> make newFilex the inputs, read/merge the records from those chunks
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> outputting to another file1, when you reach the end of the first chunk in
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> the files you then read/merge the second chunk into another file2. You
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> repeat this process until you end up with only one chunk in one file.
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> --
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> Wulfraed Dennis Lee Bieber AF6VN
>
> wlfraed at ix.netcom.com HTTP://wlfraed.home.netcom.com/
The way you mentioned for merging the file is an option but that will involve a lot of I/O operation. Also, I do not want the size of the file to increase beyond a certain point. When I reach the file size upto a certain limit, I want to start writing in a new file. This is because I want to store them in memory again later.
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