Dears,
I would like to count the number of "(" and ")" that occur in a file.
(syntax checking script). I tried to use "grep -c" and this works fine as long as there is only one character (for which I do a search) on a line.
Has anyone an idea how I can count the number of specific characters... (6 Replies)
I have a comma delimited file that roughly has 300 fields. Not all fields are populated.
This file is fed into another system, what I need to do is count the amount of characters in each field and give me an output similiar to this:
1 - 6,2 - 25
The first number is the field and the second... (2 Replies)
I want to list the occurence of particular characters in a line. my file looks like this
a,b,c,d
e,f,g
h,y:e,g,y s
f;g,s,w
and I want to count how many commas are in each line so the file in the end looks like this:
a,b,c,d 3
e,f,g 2
h,y:e,g,y s 3
f;g,s,w ... (2 Replies)
Ok say I wanted to count every Y in a data file.
Then set Y as my delimiter so that I can separate my file by taking all the contents that occur BEFORE the first Y and store them in a variable so that I may use this content later on in my program. Then I could do the same thing with the next Y's... (5 Replies)
I do have a big file in the following format
>A1
ATGCGG
>A2
TCATGC
>A3
-TGCTG
The number of characters will be same under each subheader and only possible characters are A,T,G,C and -
I want to count the number of A's, T's,G's, C's & -'s vertically for all the positions so that I... (5 Replies)
Hi All, here's a question from newbie
I have a data like this, which set of small DNA sequences separated by new line
GAATCCGGAAACAGCAACTTCAAANCA
GTNATTCGGGCCAAACTGTCGAA
TTNGGCAACTGTTAGAGCTCATGCGACA
CCTGCTAAACGAGTTCGAGTTGAANGA
TTNCGGAAGTGGTCGCTGGCACGG
ACNTGCATGTACGGAGTGACGAAACCI... (6 Replies)
Discussion started by: amits22
6 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)
07-02-2010
vgersh99,