A slight simplification of pravin27's script:
As always, if you want to try this on a Solaris/SunOS system, use /usr/xpg4/bin/awk, /usr/xpg6/bin/awk, or nawk instead of just awk.
These 2 Users Gave Thanks to Don Cragun For This Post:
Hi guys,
I need some help to come out with a solution . I have seven such files but I am showing only three for convenience.
filea
a5 20
a8 16
fileb
a3 42
a7 14
filec
a5 23
a3 07
The output file shoud contain the data in table form showing first field of... (7 Replies)
Hello,
I have two files that I need to compare and print out the line from file2 that has the first 6 fields matching the first 6 fields in file1. Complicating this are the following restrictions
1. file1 is only a few thousand lines at most and file2 is greater than 2 million
2. I need to... (7 Replies)
I have to files
File1
1 23
2 34
3 7
4 56
5 61
6 22
7 65
File2
2 21
4 32
7 22
Now i need to compare column1 of both the files and generate a third file which should contain all the values of 1st column of 1st file and in the second column i need to get the coressponding row... (2 Replies)
Hello. I have two files. FILE1 was extracted from FILE2 and modified thanks to help from this post. Now I need to replace the extracted, modified lines into the original file (FILE2) to produce the FILE3.
FILE1
1466 55.27433 14.72050 -2.52E+03 3.00E-01 1.05E+04 2.57E+04
1467 55.27433... (1 Reply)
Hi friends,
I have multiple files. For now, let's say I have two of the following style
cat 1.txt
cat 2.txt
output.txt
Please note that my files are not sorted and in the output file I need another extra column that says the file from which it is coming. I have more than 100... (19 Replies)
Good morning all,
I have a problem that is one step beyond a standard awk compare.
I would like to compare three files which have several thousand records against a fourth file. All of them have a value in each row that is identical, and one value in each of those rows which may be duplicated... (1 Reply)
Hi,
I want to compare two columns from file1 with another two column of file2 and print matched and unmatched column like this
File1
1 rs1 abc
3 rs4 xyz
1 rs3 stu
File2
1 kkk rs1 AA 10
1 aaa rs2 DD 20
1 ccc ... (2 Replies)
I want to print only the lines in file2 that match file1, in the same order as they appear in file 1
file1
file2
desired output:
I'm getting the lines to match
awk 'FNR==NR {a++}; FNR!=NR && a' file1 file2
but they are in sorted order, which is not what I want:
Can anyone... (4 Replies)
I have requirement to split below file (sample.csv) into multiple files by using the unique columns (first 3 are unique columns)
sample.csv
123|22|56789|ABCDEF|12AB34|2019-07-10|2019-07-10|443.3400|1|1
123|12|5679|BCDEFG|34CD56|2019-07-10|2019-07-10|896.7200|1|2... (3 Replies)
Discussion started by: RVSP
3 Replies
LEARN ABOUT DEBIAN
bup-margin
bup-margin(1) General Commands Manual bup-margin(1)NAME
bup-margin - figure out your deduplication safety margin
SYNOPSIS
bup margin [options...]
DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two
entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.
For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit
hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by
its first 46 bits.
The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits,
that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits
with far fewer objects.
If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if
you're getting dangerously close to 160 bits.
OPTIONS --predict
Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer
from the guess. This is potentially useful for tuning an interpolation search algorithm.
--ignore-midx
don't use .midx files, use only .idx files. This is only really useful when used with --predict.
EXAMPLE
$ bup margin
Reading indexes: 100.00% (1612581/1612581), done.
40
40 matching prefix bits
1.94 bits per doubling
120 bits (61.86 doublings) remaining
4.19338e+18 times larger is possible
Everyone on earth could have 625878182 data sets
like yours, all in one repository, and we would
expect 1 object collision.
$ bup margin --predict
PackIdxList: using 1 index.
Reading indexes: 100.00% (1612581/1612581), done.
915 of 1612581 (0.057%)
SEE ALSO bup-midx(1), bup-save(1)BUP
Part of the bup(1) suite.
AUTHORS
Avery Pennarun <apenwarr@gmail.com>.
Bup unknown-bup-margin(1)