Sponsored Content
Full Discussion: how to choose random columns
Top Forums Shell Programming and Scripting how to choose random columns Post 302516103 by mira on Thursday 21st of April 2011 04:19:55 PM
Old 04-21-2011
Question how to choose random columns

Hello!

Can anybody suggest about the fastest way of extracting "n" random columns from a very large file (tab separated) having thousands of columns, where n can be any specified number.

Thanks!
 

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

choose random text between constant string.. using awk?

Hallo I have maybe a little bit advanced request.... I need to choose one random part betwen %.... so i have this.. % text1 text1 text1 text1 text1 text1 text1 text1 text1 % text2 text2 text2 text2 text2 % text3 text3 text3 tetx3 % this choose text between % awk ' /%/... (8 Replies)
Discussion started by: sandwich
8 Replies

2. Shell Programming and Scripting

choose y or n

Hi, I have written a choice based shell script some thing like this: if (y) execute code .... fi else if(n) terminating the problem with the above scripting is it will work as far as the options are y or n. but i want to reiterate the same code when the user inputs something else... (1 Reply)
Discussion started by: sunrexstar
1 Replies

3. Ubuntu

expect script for random password and random commands

Hi I am new to expect. Please if any one can help on my issue its really appreciable. here is my issue: I want expect script for random passwords and random commands generation. please can anyone help me? Many Thanks in advance (0 Replies)
Discussion started by: vanid
0 Replies

4. What is on Your Mind?

Which Tablet to Choose?

Currently in the process of looking for a tablet. Which one is best? Thanks Benjamin Mauerberger (9 Replies)
Discussion started by: hlinks12
9 Replies

5. Shell Programming and Scripting

choosing random columns from a file

Hello, I want to choose random columns from big file. for example: My file contain around 21000 columns and I want to randomly extract 4000 columns from this file. Anybody has a solution (may be one liner or a function in perl or awk) for this? Thanks, R (2 Replies)
Discussion started by: ryan9011
2 Replies

6. Shell Programming and Scripting

Need to generate a file with random data. /dev/[u]random doesn't exist.

Need to use dd to generate a large file from a sample file of random data. This is because I don't have /dev/urandom. I create a named pipe then: dd if=mynamed.fifo do=myfile.fifo bs=1024 count=1024 but when I cat a file to the fifo that's 1024 random bytes: cat randomfile.txt >... (7 Replies)
Discussion started by: Devyn
7 Replies

7. Shell Programming and Scripting

Selecting random columns from large dataset in UNIX

Dear folks I have a large data set which contains 400K columns. I decide to select 50K determined columns from the whole 400K columns. Is there any command in unix which could do this process for me? I need to also mention that I store all of the columns id in one file which may help to select... (5 Replies)
Discussion started by: sajmar
5 Replies

8. Shell Programming and Scripting

Script that will random choose an IP address

Hi, I need to write a bash script that will random choose and login into these below ip addresses. 192.168.116.130 192.168.116.131 192.168.116.132 192.168.116.133 I'm new into scripting and I need to enhance my logic. Below is what i did ... (4 Replies)
Discussion started by: Milon
4 Replies

9. UNIX for Beginners Questions & Answers

Which Product to Choose?

Okay, I have an Asus A8NSLI board with an Athlon 64 and I dunno, maybe 8gig Ram and Windows has crashed for the last time so I've finally had enough and I'll make it a Unix machine. I have a new 1Tera drive and I'm all set to go. Which brand of Unix/Linux can you advise me to go for? The... (3 Replies)
Discussion started by: abrogard
3 Replies
TABS(1) 						    BSD General Commands Manual 						   TABS(1)

NAME
tabs -- set terminal tabs SYNOPSIS
tabs [-n | -a | -a2 | -c | -c2 | -c3 | -f | -p | -s | -u] [+m[n]] [-T type] tabs [-T type] [+[n]] n1[,n2,...] DESCRIPTION
The tabs utility displays a series of characters that clear the hardware terminal tab settings then initialises tab stops at specified posi- tions, and optionally adjusts the margin. In the first synopsis form, the tab stops set depend on the command line options used, and may be one of the predefined formats or at regular intervals. In the second synopsis form, tab stops are set at positions n1, n2, etc. If a position is preceded by a '+', it is relative to the previous position set. No more than 20 positions may be specified. If no tab stops are specified, the ``standard'' UNIX tab width of 8 is used. The options are as follows: -n Set a tab stop every n columns. If n is 0, the tab stops are cleared but no new ones are set. -a Assembler format (columns 1, 10, 16, 36, 72). -a2 Assembler format (columns 1, 10, 16, 40, 72). -c COBOL normal format (columns 1, 8, 12, 16, 20, 55) -c2 COBOL compact format (columns 1, 6, 10, 14, 49) -c3 COBOL compact format (columns 1, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62, 67). -f FORTRAN format (columns 1, 7, 11, 15, 19, 23). -p PL/1 format (columns 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61). -s SNOBOL format (columns 1, 10, 55). -u Assembler format (columns 1, 12, 20, 44). +m[n], +[n] Set an n character left margin, or 10 if n is omitted. -T type Output escape sequence for the terminal type type. ENVIRONMENT
The LANG, LC_ALL, LC_CTYPE and TERM environment variables affect the execution of tabs as described in environ(7). The -T option overrides the setting of the TERM environment variable. If neither TERM nor the -T option are present, tabs will fail. EXIT STATUS
The tabs utility exits 0 on success, and >0 if an error occurs. SEE ALSO
expand(1), stty(1), tput(1), unexpand(1), termcap(5) STANDARDS
The tabs utility conforms to IEEE Std 1003.1-2001 (``POSIX.1''). HISTORY
A tabs utility appeared in PWB UNIX. This implementation was introduced in FreeBSD 5.0. BUGS
The current termcap(5) database does not define the 'ML' (set left soft margin) capability for any terminals. BSD
May 20, 2002 BSD
All times are GMT -4. The time now is 08:10 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy