With your sample data contained in a file named database.txt, any of the following commands:
produce the output:
As always, without knowing what utility will be using a regular expression, we don't know the type of regular expression nor how that RE will need to be delimited to get the results you want.
Hi,
I remember once seeing a way to get the left most string in a word.
Let's say: a="First.Second.Third" (separated by dot)
echo ${a#*.} shows --> Second.Third
echo ${a##*.} shows --> Third
How do I get the the left most string "First" Or "First.Second" ???
Tried to replace #... (2 Replies)
Hi all, this is driving me nuts.
I need to evaluate if a variable in a shell script has a heading s or m character e.g. s92342394 or m9233489 if so then I need to get rid of them. I'm quite familiar with PERL and could do it there in 3 mins but I have not found a decent way to do this in a shell.... (1 Reply)
I am attempting to convert rewrite rules to Nginx, and since due to the mass amount of rewrites we must convert, I've been trying to write a script to help me on a specific part, easily.
So far I have this:
rewrite ^action/static/(+)/$ staticPage.php?pg=$1&%$query_string;
What I want done... (5 Replies)
My input contains a single word lines.
From each line
data.txt
prjtestBlaBlatestBlaBla
prjthisBlaBlathisBlaBla
prjthatBlaBladpthatBlaBla
prjgoodBlaBladpgoodBlaBla
prjgood1BlaBla123dpgood1BlaBla123
Desired output -->
data_out.txt
prjtestBlaBla
prjthisBlaBla... (8 Replies)
Hello,
I am working on an Urdu to Hindi dictionary which has the following structure:
a=b
a=c
n=d
n=q
and so on.
i.e. Headword separated from gloss by a =
I am giving below a live sample
بتا=बता
بتا=बित्ता
بتا=बुत्ता
بتان=बतान
بتان=बितान
بتانا=बिताना
I need the following... (3 Replies)
Hi,
I have pipe separated file which contains some data having comma(,) in it. I want to remove the comma(,) only from particular column without changing data in other columns.
Below is the sample data file, I want to remove the comma(,) only from 5th column.
$ cat file1
ABC | DEF, HIJ|... (6 Replies)
Hi to you all,
I'm just struggling with a regex problem and I'm pretty sure that I'm missing sth obvious... :confused:
I need a regex to feed my grep in order to find lines that contain one string but not the other.
Here's the data example:
2015-04-08 19:04:55,926|xxxxxxxxxx| ... (11 Replies)
Have Pipe Delimited File:
> BRYAN BAKER|4/4/2015|518 VIRGINIA AVE|TEST
> JOE BAXTER|3/30/2015|2233 MockingBird RD|ROW2On 3rd column where the address is located, I want to add a space after every numeric value - basically doing a "s//&\ / ":
> BRYAN BAKER|4/4/2015|5 1 8 VIRGINIA AVE|TEST
> JOE... (5 Replies)
Hi all,
I want to extract rows with the pattern ALPHANUMERIC/ALPHANUMNERIC in the 2nd column.
I dont wan rows with more than 1 slash or without any slash in 2nd column.
a a/b
b a/b/c
c a/b//c
d t/y
e r
f /f
I came up with the regex
grep '\/$' file
a a/b
b a/b/c
d t/y (3 Replies)
Discussion started by: jianp83
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)