Hello!
Is it anyone who might know how to extract the n last lines from a file, typically the 1000 last? Until know I have used sed -n np filename, but it takes each line separately, and is hence very time consuming.
Thank you in advance! (3 Replies)
Match column 3 in file1 to column 1 in file 2 and replace with column 2 from file2
file 1 sample
SNDK 80004C101 AT
XLNX 983919101 BB
NETL 64118B100 BS
AMD 007903107 CC
KLAC 482480100 DC
TER 880770102 KATS
ATHR 04743P108 KATS... (7 Replies)
Can anyone please help with this? I have 2 files as given below.
If 2nd column of file1 has pattern foo1@a, find the matching 1st column in file2 & replace 2nd column of file1 with file2's value.
file1
abc_1 foo1@a ....
abc_1 soo2@a ...
def_2 soo2@a ....
def_2 foo1@a ........ (7 Replies)
Hi Bigshots,
I have a pattern file with two columns. I have another data file. If column 1 in the pattern file appears as the 4th column in the data file, I need to replace it (4th column of data file) with column 2 of the pattern file. If the pattern is found in any other column, it should not... (6 Replies)
Hi,
I want to replace the value in more than one column.
For one column ,following command is working -
sed 's/./$value_to_replace/$column number' file_name
e.g. suppose this is input 1111000000
command - sed 's/./M/5'
output= 1111M000000
For two column also command is like -
cat... (22 Replies)
hi i have sample data
a,b,c,d,e,g h http://mysite.xyx
z,b,d,f,e,s t http://123124#
a,b,c,i,m,nothing
d,i,j,e,w,nothing
output expected is
a,b,c,d,e,http://mysite.xyx
z,b,d,f,e,http://123124#
a,b,c,i,m,nothing
d,i,j,e,w,nothing
i can get only links using grep -o 'http.*'
i... (8 Replies)
Hi Experts,
Please bear with me, i need help
I am learning AWk and stuck up in one issue.
First point : I want to sum up column value for column 7, 9, 11,13 and column15 if rows in column 5 are duplicates.No action to be taken for rows where value in column 5 is unique.
Second point : For... (12 Replies)
I have a csv which has lot of columns . I was looking for an awk script which would extract a column twice. for the first occurance the header and data needs to be intact but for the second occurance i want to replace the header name since it a duplicate and extract year value which is in ddmmyy... (10 Replies)
file1:
Name,Threshold,Curr Samples,Curr Error%,Curr ART
GETHome,100,21601,0.00%,47
GETregistry,100,21592,0.00%,13
GEThomeLayout,100,30466,0.00%,17
file2:
Name,Threshold,Curr Samples,Curr Error%,Curr ART
GETHome,100,21601,0.00%,33
GETregistry,100,21592,0.00%,22... (6 Replies)
Discussion started by: Raghuram717
6 Replies
LEARN ABOUT MOJAVE
bytes5.18
bytes(3pm) Perl Programmers Reference Guide bytes(3pm)NAME
bytes - Perl pragma to force byte semantics rather than character semantics
NOTICE
This pragma reflects early attempts to incorporate Unicode into perl and has since been superseded. It breaks encapsulation (i.e. it
exposes the innards of how the perl executable currently happens to store a string), and use of this module for anything other than
debugging purposes is strongly discouraged. If you feel that the functions here within might be useful for your application, this possibly
indicates a mismatch between your mental model of Perl Unicode and the current reality. In that case, you may wish to read some of the perl
Unicode documentation: perluniintro, perlunitut, perlunifaq and perlunicode.
SYNOPSIS
use bytes;
... chr(...); # or bytes::chr
... index(...); # or bytes::index
... length(...); # or bytes::length
... ord(...); # or bytes::ord
... rindex(...); # or bytes::rindex
... substr(...); # or bytes::substr
no bytes;
DESCRIPTION
The "use bytes" pragma disables character semantics for the rest of the lexical scope in which it appears. "no bytes" can be used to
reverse the effect of "use bytes" within the current lexical scope.
Perl normally assumes character semantics in the presence of character data (i.e. data that has come from a source that has been marked as
being of a particular character encoding). When "use bytes" is in effect, the encoding is temporarily ignored, and each string is treated
as a series of bytes.
As an example, when Perl sees "$x = chr(400)", it encodes the character in UTF-8 and stores it in $x. Then it is marked as character data,
so, for instance, "length $x" returns 1. However, in the scope of the "bytes" pragma, $x is treated as a series of bytes - the bytes that
make up the UTF8 encoding - and "length $x" returns 2:
$x = chr(400);
print "Length is ", length $x, "
"; # "Length is 1"
printf "Contents are %vd
", $x; # "Contents are 400"
{
use bytes; # or "require bytes; bytes::length()"
print "Length is ", length $x, "
"; # "Length is 2"
printf "Contents are %vd
", $x; # "Contents are 198.144"
}
chr(), ord(), substr(), index() and rindex() behave similarly.
For more on the implications and differences between character semantics and byte semantics, see perluniintro and perlunicode.
LIMITATIONS
bytes::substr() does not work as an lvalue().
SEE ALSO
perluniintro, perlunicode, utf8
perl v5.18.2 2013-11-04 bytes(3pm)