Hello,
With the following small script I list the size of documents belonging to a certain user by each time selecting the bytes-field of that file ($7). Now it fills the array with every file it finds so in the end the output of some users contains up to 200.000 numbers. So how can I calculate... (7 Replies)
Hi Eveyone,
I am working on one shell script to find the specific records from data file and add the totals into variables and print them. you can find the sample data file below for more clarification.
Sample Data File:
PXSTYL00__20090803USA
CHCART00__20090803IND... (7 Replies)
I need to go through files in a folder and names that match write to a new file and have counts of the seperate names. fairly new to scripting and know what I want but do not know how to script it. example of what I need follows
PACKAGE='ls -A1 | tr -s '-' '^' | cut -f2 -d"^" | sort -n'
loop... (2 Replies)
Hello,
I have written a script in a previous server and its being migrated to a new server. I'm trying to debug my script since i've had to make minor changes to it to get it to work.
I'm having a hard time getting my totals to populate
here is the syntax
DUMP_COUNT=`sqlplus -S... (4 Replies)
I have two files, uploads.txt and downloads.txt. I would like to combine the columns of these files based on the ip address. How can I best do this?
Uploads.txt
192.168.0.147 1565369
192.168.0.13 1664855
192.168.0.6 1332868
Downloads.txt
192.168.0.147 9838820
192.168.0.18 12051718... (7 Replies)
Afternoon,
I have a script which creates/modifies data into a formatted csv.
The trailer record should display 2 columns, the first is a static entry of "T" to identify it as a trailer record. The 2nd is a total of amounts in a column throughout the entire file.
My total isn't displaying... (8 Replies)
Hi,
I have a similar input format-
A_1 2
B_0 4
A_1 1
B_2 5
A_4 1
and looking to print in this output format with headers. can you suggest in awk?awk because i am doing some pattern matching from parent file to print column 1 of my input using awk already.Thanks!
letter number_of_letters... (5 Replies)
I have a one-liner script like this that gives a total of everything in various directories:
for i in *;
do (cd $i && cd statelist && echo $i && ls -la |awk 'NR>3 {SUM += $5}\
END { print "Total number of elements " SUM }');done
It works just great but at the end I want to print a grand... (3 Replies)
I would like to create bins to get histogram with totals and percentage, e.g. starting from 0.
If possible to set the minimum and maximum value in the bins ( in my case value min=0 and max=20 )
Input file
8 5
10 1
11 4
12 4
12 4
13 5
16 7
18 9
16 9
17 7
18 5
19 5
20 1
21 7 (10 Replies)
Discussion started by: jiam912
10 Replies
LEARN ABOUT SUSE
sort
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;
BEGIN {
$current = sort::current(); # identify prevailing algorithm
}
DESCRIPTION
With the "sort" pragma you can control the behaviour of the builtin "sort()" function.
In Perl versions 5.6 and earlier the quicksort algorithm was used to implement "sort()", but in Perl 5.8 a mergesort algorithm was also
made available, mainly to guarantee worst case O(N log N) behaviour: the worst case of quicksort is O(N**2). In Perl 5.8 and later,
quicksort defends against quadratic behaviour by shuffling large arrays before sorting.
A stable sort means that for records that compare equal, the original input ordering is preserved. Mergesort is stable, quicksort is not.
Stability will matter only if elements that compare equal can be distinguished in some other way. That means that simple numerical and
lexical sorts do not profit from stability, since equal elements are indistinguishable. However, with a comparison such as
{ substr($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
complicated 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
As of Perl 5.10, this pragma is lexically scoped and takes effect at compile time. In earlier versions its effect was global and took
effect at run-time; the documentation suggested using "eval()" to change the behaviour:
{ 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
}
Such code no longer has the desired effect, for two reasons. Firstly, the use of "eval()" means that the sorting algorithm is not changed
until runtime, by which time it's too late to have any effect. Secondly, "sort::current" is also called at run-time, when in fact the
compile-time value of "sort::current" is the one that matters.
So now this code would be written:
{ use sort qw(defaults _quicksort); # force quicksort
no sort "stable"; # stability not wanted
my $current;
BEGIN { $current = print sort::current; }
print "$current
";
@a = sort @b;
# Pragmas go out of scope at the end of the block
}
{ use sort qw(defaults stable); # force stability
my $current;
BEGIN { $current = print sort::current; }
print "$current
";
@c = sort @d;
}
perl v5.12.1 2010-04-26 sort(3pm)