I am using HP UX and think this may be done with awk but bot sure.
I have a file with a several header records and undeneath many detail records I need to put in the header record the number of detail records above this header record and number of detail records below this header record
Header... (5 Replies)
Hi
I have a file having 1000 rows. Now I would like to remove 10 rows from it. Plz give me the script.
Eg:
input file like
4 1 4500.0 1
5 1 1.0 30
6 1 1.0 4500
7 1 4.0 730
7 2 500000.0 730
8 1 785460.0 45
8 7 94255.0 30
9 1 31800.0 30
9 4 36000.0 30
10 1 15000.0 30... (5 Replies)
I need to delete rows based on the number of lines in a different file, I have a piece of code with me working but when I merge with my C application, it doesnt work.
sed '1,'\"`wc -l < /tmp/fileyyyy`\"'d' /tmp/fileA > /tmp/filexxxx
Can anyone give me an alternate solution for the above (2 Replies)
Hi,
Someone hacked my site(s) and appended a header to every .php file in every domain. With several Word Press sites, you can imagine how many files that is! I hand edited some, but it is just a huge task to edit the thousands of files.
I was a long time Linux scripter, but have not done... (5 Replies)
Hi all,
I have the following input - the unique row key is 1st column
cat file.txt
A response
C request
C response
D request
C request
C response
E request
The desired output should be
C request (7 Replies)
Greetings!
I have been trying to find out a way to take a CSV file with a large number of rows, and a very large number of columns (in the thousands) and convert the rows to a single column of data, where the first row is a header representing the attribute name and the subsequent series of... (3 Replies)
Hello There...
I have a sample input file ..
number:department:amount
125:Market:125.23
126:Hardware store:434.95
127:Video store:7.45
128:Book store:14.32
129:Gasolline:16.10
I will be doing some manipulations on all the records except the header, but the header should always be... (2 Replies)
Hi All,
I am new to UNIX . Please help me in writing code to delete all records from the file where all columns after cloumn 5 in file is either 0, #MI or NULL.
Initial 5 columns are string
e.g.
"alsod" "1FEV2" "wjwroe" " wsse" "hd3" 1 2 34 #Mi
"malasl" "wses" "trwwwe" " wsse" "hd3" 1 2 0... (4 Replies)
Hello.
A find command return a list of file.
For each fileReplace the content starting with the first "§" (of two) ending with last "ɸ" (of two), regardless of the content ( five lines )
by the following content (exactly) :
§2019_08_23§ #
# ... (8 Replies)
Discussion started by: jcdole
8 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)