If I want to find the sum of the square value of all elements in an array,
would that be
The problem I am trying to find a variance, using var(X)=<X^2>-<X>^2
and I am getting a negative value (wrong, var>0 ALWAYS). So I suspect
my procedure is wrong.
#!/usr/bin/perl -w
use strict;
open(FH,"$ARGV") or die;
my @temp=<FH>;
close FH;
my $mean = Mean(\@temp);
my $var = variance(\@temp);
print "$var\n";
sub estimate_variance {
my ($arrayref) = @_;
my ($mean,$result) = (mean($arrayref),0);
foreach (@$arrayref) {... (4 Replies)
Here I want to calculate mean,variance and sum from a file
1.1*2*4*22*211*22*12*22*22*11
2.2*2*22*12*22*11*11*122*33*22
3.9*7*22*88*87*98*67*66*56*66*11
As this is a large file and i am trying to write in c
where formulae of
MEAN = 1/N (X1...+..Xn)
Variance = square root of 1/N-1... (9 Replies)
Hi All'
I'm a newbe, and just is started to learn unix.
Where can I find a complete sample scripts? I looking for a sample scripts which log in at another unix host and and execute another script server side.
Any input welcome (5 Replies)
Hi all,
I am attempting to calculate a running variance for a file containing a column of numbers. I am using the formula variance=sum((x-mean(x))^2)/(n-1), where x is the value on the current row, and mean(x) is the average of all of the values up until that row. n represents the total number... (1 Reply)
Hi,
I am running a script sample.sh in bash environment .In the script i am using sed and awk commands which when executed individually from terminal they are getting executed normally but when i give these sed and awk commands in the script it is giving the below errors :-
./sample.sh: line... (12 Replies)
Below is the code. Its the 1st line of a file.
How can I remove the bracket and display like below.
123 web int 1 09:30:45 2013
I dont want to use AWK or SED or PERL. I need to use only the bash shell scripting commands to do it. (3 Replies)
hi gurus ,
i want the command to get the output in the desired format .
basically to convert columns to rows.
please refer to the attachment. (3 Replies)
In the awk below the first sample MEV45 gets extracted from the html, but the subsequent MEV46 and MEV47 do not as they are not part of parse. I can not seem to add them to the code. Thank you very much @RudiC your awk is very nice :).
input
{"barcodeId": "IonXpress", "barcodedSamples":... (3 Replies)
11☺Hi,
I have to data sets:
One is in .txt format and other is in .csv format, please refer below two outputs from two files.
File1.txt
SOURCE PAYDATE TOTAL_DOLLARS RECORD_COUNT
ASSET 05/25/2018 247643.94
ASSET 06/20/2018 ... (27 Replies)
Discussion started by: Tahir_M
27 Replies
LEARN ABOUT DEBIAN
devel::refcount
Devel::Refcount(3pm) User Contributed Perl Documentation Devel::Refcount(3pm)NAME
"Devel::Refcount" - obtain the REFCNT value of a referent
SYNOPSIS
use Devel::Refcount qw( refcount );
my $anon = [];
print "Anon ARRAY $anon has " . refcount($anon) . " reference
";
my $otherref = $anon;
print "Anon ARRAY $anon now has " . refcount($anon) . " references
";
DESCRIPTION
This module provides a single function which obtains the reference count of the object being pointed to by the passed reference value.
FUNCTIONS
$count = refcount($ref)
Returns the reference count of the object being pointed to by $ref.
COMPARISON WITH SvREFCNT
This function differs from "Devel::Peek::SvREFCNT" in that SvREFCNT() gives the reference count of the SV object itself that it is passed,
whereas refcount() gives the count of the object being pointed to. This allows it to give the count of any referent (i.e. ARRAY, HASH,
CODE, GLOB and Regexp types) as well.
Consider the following example program:
use Devel::Peek qw( SvREFCNT );
use Devel::Refcount qw( refcount );
sub printcount
{
my $name = shift;
printf "%30s has SvREFCNT=%d, refcount=%d
",
$name, SvREFCNT($_[0]), refcount($_[0]);
}
my $var = [];
printcount 'Initially, $var', $var;
my $othervar = $var;
printcount 'Before CODE ref, $var', $var;
printcount '$othervar', $othervar;
my $code = sub { undef $var };
printcount 'After CODE ref, $var', $var;
printcount '$othervar', $othervar;
This produces the output
Initially, $var has SvREFCNT=1, refcount=1
Before CODE ref, $var has SvREFCNT=1, refcount=2
$othervar has SvREFCNT=1, refcount=2
After CODE ref, $var has SvREFCNT=2, refcount=2
$othervar has SvREFCNT=1, refcount=2
Here, we see that SvREFCNT() counts the number of references to the SV object passed in as the scalar value - the $var or $othervar
respectively, whereas refcount() counts the number of reference values that point to the referent object - the anonymous ARRAY in this
case.
Before the CODE reference is constructed, both $var and $othervar have SvREFCNT() of 1, as they exist only in the current lexical pad. The
anonymous ARRAY has a refcount() of 2, because both $var and $othervar store a reference to it.
After the CODE reference is constructed, the $var variable now has an SvREFCNT() of 2, because it also appears in the lexical pad for the
new anonymous CODE block.
PURE-PERL FALLBACK
An XS implementation of this function is provided, and is used by default. If the XS library cannot be loaded, a fallback implementation in
pure perl using the "B" module is used instead. This will behave identically, but is much slower.
Rate pp xs
pp 225985/s -- -66%
xs 669570/s 196% --
SEE ALSO
o Test::Refcount - assert reference counts on objects
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2011-11-15 Devel::Refcount(3pm)