that is a name followed be a descriptive number.
I want to make these numbers sequential starting from 0 but without changing the "neighbours" each name belongs to. So the above should be:
Hi Unix gurus,
I have a file. I need to insert sequential number at the starting of the file. Fields are delimited by "|". I know the starting number.
Example:
File is as follows
|123|4test|test
|121|2test|test
|x12|1test|test
|vd123|5test|test
starting number is : 120
... (7 Replies)
We have to convert a sequential file to a 80 char line sequential file (HP UX platform).The sequential file contains special characters. which after conversion of the file to line sequential are getting coverted into "new line" or "tab" and file is getting distorted. Is there any way to read these... (2 Replies)
hey,
I have a file with numbers in US notation (1,000,000.00) as well as european notation (1.000.000,00)
i want all the numbers to be in european notation.
the numbers are in a text file, so to prevent that the regex also changes the commas in a sentence/text i thought of:
sed 's/,/\./'... (2 Replies)
Hi there,
Firstly, I have no experience with shell scripts so would really appreciate some help.
I have the following shell script that is causing some problems:
moveit()
{
&& set -x
if
then
DOUBLE_DELIVERY=$(grep... (6 Replies)
Writing a Tool to simulate non-sequential disk I/O (simulate db file sequential read) in C POSIX
I have over the years come across the same issue a couple of times, and it normally is that the read speed on SAN is absolutely atrocious when doing non-sequential I/O to the disks. Problem being of... (7 Replies)
I can rename a file with sequential numbers from 1 to N with this script:
num=1
for file in *.dat;do
mv "$file" "$(printf "%u" $num).txt"
let num=num+1
done
The script begins with renaming a some.dat file to 1.dat.txt and goes on sequentially renaming other DAT files to... (1 Reply)
Hi All,
I am looking for a simple way to write numbers to a file sequentially starting from 1 and ending on a specified upper limit. Example of the output file is below
Example
1
2
3
4
5
.
.
.
.
1000
please let me know the best way to do it. (10 Replies)
Hello,
Although I have found similar questions, I could not find
advice that could help with my problem. The issue:
I am trying to replace all occurrences of a regex, but
I cannot make the regex groups work together.
This is a simple input test file:
The Vedanta Philosophy... (3 Replies)
Hi experts, I've been struggling to format a large genetic dataset. It's complicated to explain so I'll simply post example input/output
$cat input.txt
ID GENE pos start end
blah1 coolgene 1 3 5
blah2 coolgene 1 4 6
blah3 coolgene 1 4 ... (4 Replies)
I am trying to output a tab-delimited result that uses the data from a tab-delimited file to combine and subtract specific lines.
If $4 matches in each line then the first matching sequential $6 value is added to $2, unless the value is 1, then the original $2 is used (like in the case of line... (3 Replies)
Discussion started by: cmccabe
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)