Hello,
I have what is probably a simple task in text manipulation, but I just can't wrap my brain around it.
I have a text file that looks something like the following. Note that some have middle initials in the first field and some don't.
john.r.smith:john.smith@yahoo.com... (4 Replies)
Hello,
say suppose i am processing an file emp.dat the field of which are
deptno empno empname etc
now say suppose i want to change the file to emp.lst then how can i do it? Here i what i attempted but in vain
BEGIN{
system("sort emp.dat > emp.lst")
FILENAME="emp.lst"
}
{
print... (2 Replies)
Hello,
I'm running a script on AIX to process lines in a file. I need to enclose the second column in quotation marks and write each line to a new file. I've come up with the following:
#!/bin/ksh
filename=$1
exec >> $filename.new
cat $filename | while read LINE
do
echo $LINE | awk... (2 Replies)
I am trying to process file which has following data
#23456789012345
ACNASPSA13N0N0
ACNAPCPA05N0N0
ACNAFATS11N0N0
I want to take out each line from the file and what to put in the file by name which if part of the line starting from offset 10 to 15. It means I want to create three file... (3 Replies)
I have a 3-column data file, for which I wish to print certain parts of $3
PHI PSI A(x)
-177.5 -177.5 1.0625
-177.5 -172.5 0.55
-177.5 -167.5 0.0478125
-177.5 -162.5 0
-177.5 -157.5 0.284375
-177.5 -152.5 0.187188
-177.5 -147.5 0.236875
-177.5 -142.5 0.383438
-177.5 ... (3 Replies)
Input File:
1234, 2345,abc
1,24141,gw
222,rff,sds
2232145,sdsd,121
Output file to be generated:
000001234,2345,abc
000000001,24141,gw
000000222,rff,sds
002232145,sdsd,121
i.e; the first column is padded to get 9 digits.
I tried with following: (1 Reply)
Hello,
I extracted a list of files in a directory with the command ls . However this is not my computer, so the ls functionality has been revamped so that it gives the filesizes in front like this :
This is the output of ls command : I stored the output in a file filelist
1.1M... (5 Replies)
I have one input file ABC.txt and one output DEF.txt. After the ABC is processed and created output, I want to rename ABC.txt to ABC.orig and DEF to ABC.txt. Currently when I am doing this, it does not process the input file as it cannot read and write to the same file. How can I achieve this?
... (12 Replies)
hello All, I'm new to AWK programming and learned myself few things to process a file and deal with duplicate lines, but I got into a scenario which makes me clueless to handle. Here is the scenario..
Input file:
user role
----- ----
AAA add
AAA delete
BBB delete
CCC delete
DDD ... (10 Replies)
Hi - I want to interrogate information about my poker hands, sessions are all recorded in a text file in a particular format. Each hand starts with the string <PokerStars> followed by a unique hand reference and other data like date/time. There is then all the information about each hand. My first... (5 Replies)
Discussion started by: rbeech23
5 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)