Name
Data::CloudWeights - Calculate values for an HTML tag cloud
Version
0.1.$Rev: 44 $
Synopsis
use Data::CloudWeights;
# Create a new cloud
my $cloud = Data::CloudWeights->new( \%cfg );
# Add one or more tags to the cloud
$cloud->add( $name, $count, $value );
# Calculate the tag cloud values
my $nimbus = $cloud->formation();Description
Each tag added to the cloud has a unique name to identify it, a count which represents the size of the tag and a value that is associated with the tag. The reference returned by $cloud->formation() is a list of hash refs, one hash ref per tag. In addition to the input parameters each hash ref contains the scaled size, the percentage of total and a colour value in the range hot to cold.
The cloud typically displays the tag name and count in the calculated colour with a font size set equal to the scaled value in the result
Configuration and Environment
new
$cloud = Data::CloudWeights->new( [{] attr => value, ... [}] )This is a class method, the constructor for Data::CloudWeights. Options are passed as either a list of keyword value pairs or a hash ref. Options are:
cold_colour
The six character hex colour for the smallest count in the cloud. Defaults to 0000FF (blue)
colour_pallet
An array ref of hex colour values. If the cold_colour attribute is set to null then the colour values from the pallet are used instead of calculating the colour value from the scaled count. Defaults to twelve values that give an even transition from blue to red
decimal_places
The number of decimal places returned in the size attribute. Defaults to 2. With the default values for high and low this lets you set the tags font size in ems. If set to 0 and the high/low values suitably changed tag font size can be set in pixies
hot_colour
The six character hex colour for the highest count in the cloud. Defaults to FF0000 (red)
max_size
The upper boundary value to which the highest count in the cloud is scaled. Defaults to 2.0 (ems)
min_size
The lower boundary value to which the smallest count in the cloud is scaled. Defaults to 0.66 (ems)
Subroutines/Methods
add
$cloud->add( $name, $count, $value );Adds the tag name, count, and value triple to the cloud. The formation method returns a ref to an array of hash refs. Each hash ref contains one of these triples and the calculated attributes. The value arg is optional. Passing a count of zero will do nothing but returns the current cumulative total count for this tag name
formation
$cloud->formation();Return a ref to an array of hash refs. The attributes of each hash ref are:
colour
Calculated or dereferenced via the pallet, this is the hex colour string for this tag
count
The supplied size for this tag. Multiple calls to the add method for the same tag cause these counts to accumulate
percent
The percentage of the total count that this tag represents
size
The count scaled to a value between max_size and min_size
tag
The supplied name for this tag
value
The supplied value for this tag. This is usually an href but can be any scalar. If multiple calls to add the same tag were made this will be an array ref containing each of the passed values
_hex2dec
$class->_hex2dec( $index, $hex_value );Private method converts a two character string representation of a number to a decimal integer in the range 0 - 255
_calculate_temperature
$obj->_calculate_temperature( $count );Private method used internally to calculate a colour value for a tag. If the 'hot' or 'cold' value is undefined a discreet colour value will be selected from the 'pallet' instead of calculating it using a continuous function
Diagnostics
None
Acknowledgements
- Originally WWW::CloudCreator
-
This did not let me calculate font sizes in ems
Dependencies
Incompatibilities
There are no known incompatibilities in this module.
Bugs and Limitations
There are no known bugs in this module. Please report problems to the address below. Patches are welcome.
Author
Peter Flanigan, <Support at RoxSoft.co.uk>
License and Copyright
Copyright (c) 2007 Peter Flanigan. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.
This program is distributed in the hope that it will be useful, but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.