17 comes before 12 or just a typo? 

hist:x

 1  ##
 4  ####
 5  ####
 17 ##########
 12 #

[download]
I cannot use any known database engine

Really? Why not?

If true, the first thing I would do is write a short program to do a single pass over your 2e9 silly format files and output a single file formatted like so:

1: 1(3) 3(4) 5(7) 17(1) 21(1)
2: 1(2) 3(2) 17(5) 20(1) 22(2)
3: 3(1) 10(3) 12(1)
...

[download]

Then I could dump all those silly format files.

Then I'd look to reformat that single file into some kind of consistent record format, but then I read this bit of your description:

each in real case scenario containing approx 300 columns and there is a maximum of 8000 possible column labels(values)) i thought i should create a consensus histogram from all subject ones. such that this histogram has all 25 columns (now i am again talking about my example) and each column having the maximum number of data points (this is computed from the subject set- if the max number of data points for column 1 is 100 then this how large column 1 in my consensus hist will be.)

And got completely lost in the number of columns and ranges of values for each column...

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Similarity searching by BrowserUk
in thread Similarity searching by baxy77bax

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