# Copyright 2009 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::Aroon;
use 5.010;
use strict;
use warnings;
use Carp;
use List::Util qw(min max);
use Locale::TextDomain ('App-Chart');
use base 'App::Chart::Series::Indicator';
use constant DEBUG => 0;
sub longname { __('Aroon') }
sub shortname { __('Aroon') }
sub manual { __p('manual-node','Aroon') }
use constant
{ type => 'indicator',
minimum => -100,
maximum => 100,
hlines => [ 0 ],
parameter_info => [ { name => __('Days'),
key => 'aroon_days',
type => 'integer',
minimum => 1,
default => 25 } ],
decimals => 0, # none needed normally
line_colours => { up => App::Chart::UP_COLOUR(),
down => App::Chart::DOWN_COLOUR() },
};
sub new {
my ($class, $parent, $N) = @_;
$N //= parameter_info()->[0]->{'default'};
return $class->SUPER::new
(parent => $parent,
N => $N,
parameters => [ $N ],
arrays => { up => [],
down => [],
oscillator => [] },
array_aliases => { values => 'oscillator' });
}
sub fill_part {
my ($self, $lo, $hi) = @_;
my $parent = $self->{'parent'};
my $N = $self->{'N'};
my $start = $parent->find_before ($lo, $N-1);
$parent->fill ($start, $hi);
my $p = $parent->array('values');
$hi = min ($hi, $#$p);
my $up = $self->array('up');
my $down = $self->array('down');
my $osc = $self->array('oscillator');
if ($#$up < $hi) { $#$up = $hi; } # pre-extend
if ($#$down < $hi) { $#$down = $hi; }
if ($#$osc < $hi) { $#$osc = $hi; }
my @a;
foreach my $i ($start .. $lo-1) {
my $value = $p->[$i] // next;
unshift @a, $value;
}
foreach my $i ($lo .. $hi) {
my $value = $p->[$i] // next;
# keep last $N + 1 many points
if (@a > $N) {
pop @a; # drop old
}
unshift @a, $value; # add new
# for equal highs or equal lows, the oldest is taken, on the
# theory that a new high/low has not been established but rather
# the old one is still in force
#
if (DEBUG) { require Data::Dumper;
print "Aroon on ",Data::Dumper->Dump([\@a],['a']); }
my $high_val = my $low_val = $a[0];
my $high_pos = my $low_pos = 0;
foreach my $pos (1 .. $#a) {
$value = $a[$pos];
if ($value >= $high_val) { $high_val = $value; $high_pos = $pos; }
if ($value <= $low_val) { $low_val = $value; $low_pos = $pos; }
}
if (DEBUG) { print " high_val=$high_val high_pos=$high_pos",
" low_val=$low_val low_pos=$low_pos in N=$N\n"; }
$up->[$i] = $high_pos = 100 - 100 * $high_pos / $N;
$down->[$i] = $low_pos = 100 - 100 * $low_pos / $N;
$osc->[$i] = $high_pos - $low_pos;
}
}
1;
__END__
# =head1 NAME
#
# App::Chart::Series::Derived::Aroon -- aroon oscillator
#
# =head1 SYNOPSIS
#
# my $series = $parent->Aroon($N);
#
# =head1 DESCRIPTION
#
# ...
#
# =head1 SEE ALSO
#
# L<App::Chart::Series>
#
# =cut