9 More Discussions You Might Find Interesting
1. UNIX for Beginners Questions & Answers
Hello, this is my first thread here :)
So i have a text file that contains words in each line like
abcd
efgh
ijkl
mnop
and i have 4 txt files, i want to add each line to each file, like file 1 gets abcd at the end; file 2 gets efgh at the end ....
I tried with:
cat test | while read -r... (6 Replies)
Discussion started by: azaiiez
6 Replies
2. Windows & DOS: Issues & Discussions
so...
Lets assume I have a text file.
The text file contains multiple "#" symbols.
I want to replace all thos "#"s with a STRING using DOS/Batch
I want to add a certain TEXT to the end of each line.
How can I do this WITHOUT aid of sed, grep or anything linux related ? (1 Reply)
Discussion started by: pasc
1 Replies
3. UNIX for Dummies Questions & Answers
Hi,
I have a tab delimited document with 18 columns. My file looks like:
comp1000201_c0_seq1 comp1000201_c0 337 183.51 0.00 0.00 0.00 0.00 ---NA--- 337 0 0
-
comp1000297_c0_seq1 comp1000297_c0 612 458.50 ... (1 Reply)
Discussion started by: alisrpp
1 Replies
4. Shell Programming and Scripting
Hi Guys,
I have file A.txt
File A Data
AK1521
AK2536
AK3164
I want create text file of all data above and write some data on each file.
want Output on below folder
/home/kka/out
AK1521.txt
Hi
Welocme (3 Replies)
Discussion started by: asavaliya
3 Replies
5. UNIX for Dummies Questions & Answers
I would like help adding a new column to a large txt file (~10MB) that contains the filename. I have searched other posts but have not found an adequate solution.
I need this extra column so I can concatenate >100 files and perform awk searches on this large file.
My current txt file look... (4 Replies)
Discussion started by: kellywilliams
4 Replies
6. Shell Programming and Scripting
Hi all,
I did not use UNIX for a long time, now i need to make a flat file with extra field, can you help me with the code ?
1. I create a last line of each log from each system and make it in a flat text file (seperate by a pipe |)
mv current.log old
tail -1 sanfrancisco.log > current.log... (5 Replies)
Discussion started by: britney
5 Replies
7. Shell Programming and Scripting
May i know how do i go along finding similar entry in a .txt file, which is used a as a "database" and post and error saying the entry existed when we key in the entry.
---------- Post updated at 05:18 PM ---------- Previous update was at 05:16 PM ----------
i mean post an error saying the... (5 Replies)
Discussion started by: santonio
5 Replies
8. Shell Programming and Scripting
Hi,
I have an application's log file:
/var/log/logfile which is feeded from time to time due to an application. This file contains data, what I want is:
-Whenever some new data is copied to /var/log/logfileI want to generate an email to root BUT only with the new added data in the body.... (6 Replies)
Discussion started by: iga3725
6 Replies
9. Shell Programming and Scripting
Hey guy,
how to make bash script to create foo.txt file and add current date into file content and that file always append.
example: today the script run and add today date into content foo.txt
and tomorrow the script will run and add tomorrow date in content foo.txt without remove today... (3 Replies)
Discussion started by: chenboly
3 Replies
sort(3pm) Perl Programmers Reference Guide sort(3pm)
NAME
sort - perl pragma to control sort() behaviour
SYNOPSIS
use sort 'stable'; # guarantee stability
use sort '_quicksort'; # use a quicksort algorithm
use sort '_mergesort'; # use a mergesort algorithm
use sort 'defaults'; # revert to default behavior
no sort 'stable'; # stability not important
use sort '_qsort'; # alias for quicksort
my $current = sort::current(); # identify prevailing algorithm
DESCRIPTION
With the "sort" pragma you can control the behaviour of the builtin "sort()" function.
In Perl versions 5.6 and earlier the quicksort algorithm was used to implement "sort()", but in Perl 5.8 a mergesort algorithm was also
made available, mainly to guarantee worst case O(N log N) behaviour: the worst case of quicksort is O(N**2). In Perl 5.8 and later, quick-
sort defends against quadratic behaviour by shuffling large arrays before sorting.
A stable sort means that for records that compare equal, the original input ordering is preserved. Mergesort is stable, quicksort is not.
Stability will matter only if elements that compare equal can be distinguished in some other way. That means that simple numerical and
lexical sorts do not profit from stability, since equal elements are indistinguishable. However, with a comparison such as
{ substr($a, 0, 3) cmp substr($b, 0, 3) }
stability might matter because elements that compare equal on the first 3 characters may be distinguished based on subsequent characters.
In Perl 5.8 and later, quicksort can be stabilized, but doing so will add overhead, so it should only be done if it matters.
The best algorithm depends on many things. On average, mergesort does fewer comparisons than quicksort, so it may be better when compli-
cated comparison routines are used. Mergesort also takes advantage of pre-existing order, so it would be favored for using "sort()" to
merge several sorted arrays. On the other hand, quicksort is often faster for small arrays, and on arrays of a few distinct values,
repeated many times. You can force the choice of algorithm with this pragma, but this feels heavy-handed, so the subpragmas beginning with
a "_" may not persist beyond Perl 5.8. The default algorithm is mergesort, which will be stable even if you do not explicitly demand it.
But the stability of the default sort is a side-effect that could change in later versions. If stability is important, be sure to say so
with a
use sort 'stable';
The "no sort" pragma doesn't forbid what follows, it just leaves the choice open. Thus, after
no sort qw(_mergesort stable);
a mergesort, which happens to be stable, will be employed anyway. Note that
no sort "_quicksort";
no sort "_mergesort";
have exactly the same effect, leaving the choice of sort algorithm open.
CAVEATS
This pragma is not lexically scoped: its effect is global to the program it appears in. That means the following will probably not do what
you expect, because both pragmas take effect at compile time, before either "sort()" happens.
{ use sort "_quicksort";
print sort::current . "
";
@a = sort @b;
}
{ use sort "stable";
print sort::current . "
";
@c = sort @d;
}
# prints:
# quicksort stable
# quicksort stable
You can achieve the effect you probably wanted by using "eval()" to defer the pragmas until run time. Use the quoted argument form of
"eval()", not the BLOCK form, as in
eval { use sort "_quicksort" }; # WRONG
or the effect will still be at compile time. Reset to default options before selecting other subpragmas (in case somebody carelessly left
them on) and after sorting, as a courtesy to others.
{ eval 'use sort qw(defaults _quicksort)'; # force quicksort
eval 'no sort "stable"'; # stability not wanted
print sort::current . "
";
@a = sort @b;
eval 'use sort "defaults"'; # clean up, for others
}
{ eval 'use sort qw(defaults stable)'; # force stability
print sort::current . "
";
@c = sort @d;
eval 'use sort "defaults"'; # clean up, for others
}
# prints:
# quicksort
# stable
Scoping for this pragma may change in future versions.
perl v5.8.0 2002-06-01 sort(3pm)