# Copyright 2006, 2007, 2009, 2010 Kevin Ryde
# This file is part of Chart.
#
# Chart is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 3, or (at your option) any later version.
#
# Chart is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along
# with Chart. If not, see <http://www.gnu.org/licenses/>.
package App::Chart::Series::Derived::RAVI;
use 5.010;
use strict;
use warnings;
use Carp;
use List::Util qw(min max);
use Locale::TextDomain 1.17; # for __p()
use Locale::TextDomain ('App-Chart');
use base 'App::Chart::Series::Indicator';
use App::Chart::Series::Derived::SMA;
sub longname { __('RAVI') }
*shortname = \&longname;
sub manual { __p('manual-node','RAVI') }
use constant
{ type => 'indicator',
units => 'units',
minimum => 0,
hlines => [ 3 ],
parameter_info => [ { name => __('Short Days'),
key => 'ravi_short_days',
type => 'integer',
minimum => 1,
default => 7 },
{ name => __('Long Days'),
key => 'ravi_long_days',
type => 'integer',
minimum => 1,
default => 65 }],
};
sub new {
my ($class, $parent, $short_N, $long_N) = @_;
$short_N //= parameter_info()->[0]->{'default'};
($short_N > 0) || croak "RAVI bad short N: $short_N";
$long_N //= parameter_info()->[1]->{'default'};
($long_N > 0) || croak "RAVI bad long N: $long_N";
return $class->SUPER::new
(parent => $parent,
parameters => [ $short_N, $long_N ],
arrays => { values => [] },
array_aliases => { });
}
sub warmup_count {
my ($class_or_self, $short_N, $long_N) = @_;
return App::Chart::Series::Derived::SMA->warmup_count
(max ($short_N, $long_N));
}
sub proc {
my ($self_or_class, $short_N, $long_N) = @_;
my $short_proc = App::Chart::Series::Derived::SMA->proc ($short_N);
my $long_proc = App::Chart::Series::Derived::SMA->proc ($long_N);
return sub {
my ($value) = @_;
my $short = $short_proc->($value);
my $long = $long_proc->($value);
return ($long == 0 ? undef : 100 * abs($short-$long) / $long);
};
}
1;
__END__
# =head1 NAME
#
# App::Chart::Series::Derived::RAVI -- RAVI indicator
#
# =head1 SYNOPSIS
#
# my $series = $parent->RAVI;
#
# =head1 DESCRIPTION
#
# ...
#
# =head1 SEE ALSO
#
# L<App::Chart::Series>, L<App::Chart::Series::Derived::REMA>
#
# =cut