I have a large file with fields delimited by '|', and I want to run some analysis on it. What I want to do is count how many times each field is populated, or list the frequency of population for each field.
I am in a Sun OS environment.
Thanks,
- CB (3 Replies)
Hi. I'm working with two BASH shells in order to perform two tasks. For simplicity, suppose that at Shell #1 I'm executing this program:
sleep 100
whose PID is 263. Meanwhile Shell #2 is waiting for its termination to follow with a second one.
I tried with:
wait 263
# Script for second... (4 Replies)
I have a data file that has 6 columns and I have sorted the 3rd column so that all rows are sorted according to the 3rd column (from lowest to highest number). An example is shown below:
7563 273 1 -15.81100000 25.37250000 -19.27320000
8149 294 1 -17.90540000 ... (3 Replies)
Hi guys,
Those who work with Background Oriented Schlieren (BOS) might wonder how to create image pairs suitable for a PIV image processing software.
Here is the code :
#!/bin/bash
# This is a program to read *.jpg files and save them in pairs for postprocessing
nfiles=`ls -1 bild*... (0 Replies)
I need to write a shell script "cmn" that, given an integer k, print the k most common words in descending order of frequency.
Example Usage:
user@ubuntu:/$ cmn 4 < example.txt :b: (3 Replies)
Hi, I have tab-deliminated data similar to the following:
dot is-big 2
dot is-round 3
dot is-gray 4
cat is-big 3
hot in-summer 5
I want to count the frequency of each individual "unique" value in the 1st column. Thus, the desired output would be as follows:
dot 3
cat 1
hot 1
is... (5 Replies)
Dear all,
I have an AWK script which provides frequency of words. However I am interested in getting the frequency of chunked data. This means that I have already produced valid chunks of running text, with each chunk on a line. What I need is a script to count the frequencies of each string. A... (4 Replies)
Discussion started by: gimley
4 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)