Free data software for linux

Data::Page is a Perl module that helps when paging through sets of results.

SYNOPSIS

use Data::Page;

my $page = Data::Page->new();
$page->total_entries($total_entries);
$page->entries_per_page($entries_per_page);
$page->current_page($current_page);

print " First page: ", $page->first_page, "n";
print " Last page: ", $page->last_page, "n";
print "First entry on page: ", $page->first, "n";
print " Last entry on page: ", $page->last, "n";

When searching through large amounts of data, it is often the case that a result set is returned that is larger than we want to display on one page. This results in wanting to page through various pages of data. The maths behind this is unfortunately fiddly, hence this module.

The main concept is that you pass in the number of total entries, the number of entries per page, and the current page number. You can then call methods to find out how many pages of information there are, and what number the first and last entries on the current page really are.

For example, say we wished to page through the integers from 1 to 100 with 20 entries per page. The first page would consist of 1-20, the second page from 21-40, the third page from 41-60, the fourth page from 61-80 and the fifth page from 81-100. This module would help you work this out.

Data::ENAML is a Perl extension for ENAML data representation.

SYNOPSIS

use Data::ENAML qw (serialize deserialize);

print serialize(login => {nick => Schop,
email => ariel@atheist.org.il,
tagline => If I had no modem I would not lose Regina});

$struct = deserialize(bad-nick: {nick: "c00l dewd" text: "spaces not allowed"});

ENAML stands for ENAML is Not A Markup Language. (And as we all know, Gnu is Not UNIX, Pine Is Not Email, Wine Is Not Emulator, Lame Aint Mp3 Encoder and so on).

ENAML was defined by Robey Pointer for use in Say2, check http://www.lag.net/say2.

Gimp::Data is a Perl module to set and get state data.

SYNOPSIS

use Gimp::Data;

$Gimp::Data{value1} = "Hello";
print $Gimp::Data{value1},", World!!n";

With this module, you can access plugin-specific (or global) data in Gimp, i.e. you can store and retrieve values that are stored in the main Gimp application.

An example would be to save parameter values in Gimp, so that on subsequent invocations of your plug-in, the user does not have to set all parameter values again (Gimp::Fu does this already).

Data::CTable is a Perl module that helps you read, write, manipulate tabular data.

SYNOPSIS

## Read some data files in various tabular formats
use Data::CTable;
my $People = Data::CTable->new("people.merge.mac.txt");
my $Stats = Data::CTable->new("stats.tabs.unix.txt");

## Clean stray whitespace in fields
$People->clean_ws();
$Stats ->clean_ws();

## Retrieve columns
my $First = $People->col(FirstName);
my $Last = $People->col(LastName );

## Calculate a new column based on two others
my $Full = [map {"$First->[$_] $Last->[$_]"} @{$People->all()}];

## Add new column to the table
$People->col(FullName => $Full);

## Another way to calculate a new column
$People->col(Key);
$People->calc(sub {no strict vars; $Key = "$Last,$First";});

## "Left join" records matching Stats:PersonID to People:Key
$Stats->join($People, PersonID => Key);

## Find certain records
$Stats->select_all();
$Stats->select(Department => sub {/Sale/i }); ## Sales depts
$Stats->omit (Department => sub {/Resale/i}); ## not Resales
$Stats->select(UsageIndex => sub {$_ > 20.0}); ## high usage

## Sort the found records
$Stats->sortspec(DeptNum , {SortType => Integer});
$Stats->sortspec(UsageIndex, {SortType => Number });
$Stats->sort([qw(DeptNum UsageIndex Last First)]);

## Make copy of table with only found/sorted data, in order
my $Report = $Stats->snapshot();

## Write an output file
$Report->write(_FileName => "Rept.txt", _LineEnding => "mac");

## Print a final progress message.
$Stats->progress("Done!");

## Dozens more methods and parameters available...

OVERVIEW

Data::CTable is a comprehensive utility for reading, writing, manipulating, cleaning and otherwise transforming tabular data. The distribution includes several illustrative subclasses and utility scripts.

A Columnar Table represents a table as a hash of data columns, making it easy to do data cleanup, formatting, searching, calculations, joins, or other complex operations.

The objects hash keys are the field names and the hash values hold the data columns (as array references).

Tables also store a "selection" -- a list of selected / sorted record numbers, and a "field list" -- an ordered list of all or some fields to be operated on. Select() and sort() methods manipulate the selection list. Later, you can optionally rewrite the table in memory or on disk to reflect changes in the selection list or field list.
Data::CTable reads and writes any tabular text file format including Merge, CSV, Tab-delimited, and variants. It transparently detects, reads, and preserves Unix, Mac, and/or DOS line endings and tab or comma field delimiters -- regardless of the runtime platform.

In addition to reading data files, CTable is a good way to gather, store, and operate on tabular data in memory, and to export data to delimited text files to be read by other programs or interactive productivity applications.

To achieve extremely fast data loading, CTable caches data file contents using the Storable module. This can be helpful in CGI environments or when operating on very large data files. CTable can read an entire cached table of about 120 megabytes into memory in about 10 seconds on an average mid-range computer.

For simple data-driven applications needing to store and quickly retrieve simple tabular data sets, CTable provides a credible alternative to DBM files or SQL.
For data hygiene applications, CTable forms the foundation for writing utility scripts or compilers to transfer data from external sources, such as FileMaker, Excel, Access, personal organizers, etc. into compiled or validated formats -- or even as a gateway to loading data into SQL databases or other destinations. You can easily write short, repeatable scripts in Perl to do reporting, error checking, analysis, or validation that would be hard to duplicate in less-flexible application environments.

The data representation is simple and open so you can directly access the data in the object if you feel like it -- or you can use accessors to request "clean" structures containing only the data or copies of it. Or you can build your own columns in memory and then when youre ready, turn them into a table object using the very flexible new() method.

The highly factored interface and implementation allow fine-grained subclassing so you can easily create useful lightweight subclasses. Several subclasses are included with the distribution.

Most defaults and parameters can be customized by subclassing, overridden at the instance level (avoiding the need to subclass too often), and further overridden via optional named-parameter arguments to most major method calls.