10-09-2009
How to read n number of lines from a file
Hiii
I am very new to shell scripting.This is my data file
a.txt:
56
45.78
1000
11.23
76.89
45
34.56
23
3400
100
..........
Now i am must use shell scripting to read n number of lines from the file & from ts n number of lines i need to find greatest number among them & so on for rest of the file still end of the file...
For example from the above data file
I want to check for first 3(this must be user defined) lines & so on for largest number
The ouput for such a condition must be
for first set(i.e first 3 lines)
output is 1000
then 2nd set
output is 76.89
the 3rd set
output is 3400
& so on till end of my file..
.......
Help is greatly appreciated
Thanks
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HEAD(1) User Commands HEAD(1)
NAME
head - output the first part of files
SYNOPSIS
head [OPTION]... [FILE]...
DESCRIPTION
Print the first 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With
no FILE, or when FILE is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
-c, --bytes=[-]K
print the first K bytes of each file; with the leading `-', print all but the last K bytes of each file
-n, --lines=[-]K
print the first K lines instead of the first 10; with the leading `-', print all but the last K lines of each file
-q, --quiet, --silent
never print headers giving file names
-v, --verbose
always print headers giving file names
--help display this help and exit
--version
output version information and exit
K may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P,
E, Z, Y.
AUTHOR
Written by David MacKenzie and Jim Meyering.
REPORTING BUGS
Report head bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
Report head translation bugs to <http://translationproject.org/team/>
COPYRIGHT
Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
The full documentation for head is maintained as a Texinfo manual. If the info and head programs are properly installed at your site, the
command
info coreutils 'head invocation'
should give you access to the complete manual.
GNU coreutils 8.12.197-032bb September 2011 HEAD(1)