I have a tab delimited text file where the first column can take on three different values : 100, 150, 250. I want to extract all the rows where the first column is 100 and put them into a separate text file and so on. This is what my text file looks like now:
100 rs3794811 0.01 0.3434... (1 Reply)
I have a tab delimited text file where the first column can take on three different values : 100, 150, 250. I want to extract all the rows where the first column is 100 and put them into a separate text file and so on. This is what my text file looks like now:
100 rs3794811 0.01 0.3434
100... (1 Reply)
I have a text file where the second column is a list of numbers going from small to large. I want to extract the rows where the second column is smaller than or equal to 0.0001.
My input:
rs10082730 9e-08 12 46002702
rs2544081 1e-07 12 46015487
rs1425136 1e-06 7 35396742
rs2712590... (1 Reply)
I have a space delimited text file. I want to extract rows where the third column has 0 as a value and write those rows into a new space delimited text file. How do I go about doing that? Thanks! (2 Replies)
I would like to extract the last column of a text file but different rows of the text file have different numbers of columns. How do I go about doing that? Thanks! (1 Reply)
Hi,
I have a tab delimited text file with multiple columns. The second and third columns include numbers that have not been sorted. I want to extract rows where the second column includes a value between -0.01 and 0.01 (including both numbers) and the first third column includes a value between... (1 Reply)
Hello, I have a file with nearly 57K lines. I want to filter the lines based on the range of values in a column. For e.g. print lines whose 3rd filed is >=0.02.
Input file:
LOC_Os09g32030 LOC_Os02g18880 0.0200037219149773 undirected NA NA
LOC_Os03g58630 LOC_Os09g35690 ... (1 Reply)
I have the file like this:
Timestamp URL Text 1331635241000 http://example.com Peoples footage at www.test.com,http://example4.com 1331635231000 http://example1.net crack the nuts http://example6.com 1331635280000 http://example2.net ... (0 Replies)
I have the file like this:
Timestamp URL Text 1331635241000 http://example.com Peoples footage at www.test.com,http://example4.com 1331635231000 http://example1.net crack the nuts http://example6.com 1331635280000 http://example2.net ... (0 Replies)
I have the file like this:
Timestamp URL Text 1331635241000 http://example.com Peoples footage at www.test.com,http://example4.com 1331635231000 http://example1.net crack the nuts http://example6.com 1331635280000 http://example2.net ... (3 Replies)
Discussion started by: csim_mohan
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)