I have a file in which I need to add more columns to based on a key in the first file:
File1
File2
I would like to create the following output:
Output
I'm trying to program this in Perl. My first thought is the following:
1. Fill an array with the keys in file1
2. open file2 and loop through the array on each row until i get a match then put the columns I want into a Hash of Arrays
3. Go back to the first file and apply the columns that i need to the end of the file.
However, the data sets that I'm working with are extremely big, and time is definitely an issue. Also, I think that my logic above is not the best way of doing it.
How do I add 4 columns to an excel file using Perl? The 4 headers for those columns will all have different names? Please help and I greatly appreciate... (1 Reply)
Hi Wise UNIX Crew,
I want to add 3 different columns to the file in which:
1. The first new column pulls in today's date and time
2. Second column one has a '0'
3. Third column has the word 'ANY' going down the column
If my file content is as follows:
"7","a","abc",123"... (1 Reply)
I want to select the first column from a daily file called foo.csv. The result is written to file foo.txt. Currently the following script is used for that:
cut -d, -f 1 foo.csv > foo.txt
A typical result would yield :
A12
A45
B11
B67
What needs to happen in addition is that two columns... (5 Replies)
Hi everybody,
I've got two simples file1 like:
aaa aaa aaa
bbb bbb bbb
ccc ccc ccc
and file2 like:
111 111 111
222 222 222
333 333 333
I need to:
1) add a line say "new line" as the first line of the file
2)add a column from file2 (say column3) to file1; the new column should... (14 Replies)
Good afternoon to everyone,
I have some input and output from various widgets that I am trying to get to play nicely together. Basically I would like to stay out of excel and be able to automate the entire process. I have read some posts here about how to use awk, nawk, etc, to do similar... (9 Replies)
Hi All ,
Kindly help me with this soln
awk '{printf "%s %7s \n", $1,$c}' infile
where
value of variable c I am externally giving input
But executing the above command shows all the columns of infile where as I want only 1st column of infile and 2nd column should print value c (8 Replies)
Hello,
I have a comma separated flat file. It contains some 20 columns. I want to add two new columns at position 2,3. So that file will have 22 columns. I am providing here sample data with file having 4 columns. Appreciate your help in finding solution for this.
data in input file:... (11 Replies)
Hi Everyone:
My shell script creates multiple csv files (~30) in for loop. I want to compile (or merge) 3rd column from each (all) of these files to another file (in loop). Please help. Thanks. (3 Replies)
Hello,
I am very now to this, hope you can help,
I am looking into editing a file in Solaris, with dinamic collums (lenght varies) and I need 2 things to be made, the fist is to filter the first column and third column from the file bellow file.txt, and create a new file with the 2 filtered... (8 Replies)
Discussion started by: jpbastos
8 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)