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Top Forums Shell Programming and Scripting choose random text between constant string.. using awk? Post 302394991 by drl on Sunday 14th of February 2010 07:15:27 AM
Old 02-14-2010
Hi.
Quote:
Originally Posted by ironmask2004
but you need to know how muche recoreds you have insaide the fill to generate a random number betwwen 1 and NUM Of Rec !!!
If one is willing to devote the time and effort, the reservoir sampling method allows one to extract a random sample in a single pass through a file. A brief explanation along with a python and perl code can be found at Program-o-Babble: Reservoir Sampling Algorithm in Python and Perl among many other places.

Best wishes ... cheers, drl
 

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URI::URL(3)						User Contributed Perl Documentation					       URI::URL(3)

NAME
URI::URL - Uniform Resource Locators SYNOPSIS
$u1 = URI::URL->new($str, $base); $u2 = $u1->abs; DESCRIPTION
This module is provided for backwards compatibility with modules that depend on the interface provided by the "URI::URL" class that used to be distributed with the libwww-perl library. The following differences exist compared to the "URI" class interface: o The URI::URL module exports the url() function as an alternate constructor interface. o The constructor takes an optional $base argument. The "URI::URL" class is a subclass of "URI::WithBase". o The URI::URL->newlocal class method is the same as URI::file->new_abs. o URI::URL::strict(1) o $url->print_on method o $url->crack method o $url->full_path: same as ($uri->abs_path || "/") o $url->netloc: same as $uri->authority o $url->epath, $url->equery: same as $uri->path, $uri->query o $url->path and $url->query pass unescaped strings. o $url->path_components: same as $uri->path_segments (if you don't consider path segment parameters) o $url->params and $url->eparams methods o $url->base method. See URI::WithBase. o $url->abs and $url->rel have an optional $base argument. See URI::WithBase. o $url->frag: same as $uri->fragment o $url->keywords: same as $uri->query_keywords o $url->localpath and friends map to $uri->file. o $url->address and $url->encoded822addr: same as $uri->to for mailto URI o $url->groupart method for news URI o $url->article: same as $uri->message SEE ALSO
URI, URI::WithBase COPYRIGHT
Copyright 1998-2000 Gisle Aas. perl v5.18.2 2012-02-11 URI::URL(3)
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