File Coverage

blib/lib/Math/NumSeq/DigitCountHigh.pm

Criterion	Covered	Total	%
statement	57	60	95.0
branch	7	10	70.0
condition	3	6	50.0
subroutine	15	15	100.0
pod	3	3	100.0
total	85	94	90.4

# Copyright 2010, 2011, 2012, 2013, 2014 Kevin Ryde

# This file is part of Math-NumSeq.
#
# Math-NumSeq 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.
#
# Math-NumSeq 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 Math-NumSeq.  If not, see .

package Math::NumSeq::DigitCountHigh;
use 5.004;
use strict;

use vars '$VERSION', '@ISA';
$VERSION = 71;

use Math::NumSeq;
use Math::NumSeq::Base::IterateIth;
@ISA = ('Math::NumSeq::Base::IterateIth',
        'Math::NumSeq');
*_is_infinite = \&Math::NumSeq::_is_infinite;

# uncomment this to run the ### lines
#use Devel::Comments;


# use constant name => Math::NumSeq::__('Digit Count High');
use constant description => Math::NumSeq::__('Count of how many of a given digit at the high end of a number, in a given radix.');
use constant values_min => 0;
use constant i_start => 0;
use constant characteristic_count => 1;
use constant characteristic_smaller => 1;
use constant characteristic_increasing => 0;

use Math::NumSeq::DigitCount 4;
*parameter_info_array = \&Math::NumSeq::DigitCount::parameter_info_array;

my @oeis_anum;

$oeis_anum[2]->[1] = 'A090996'; # leading 1 bits
# OEIS-Catalogue: A090996 radix=2

# OEIS-Other: A000004 radix=2 digit=0
# OEIS-Other: A000004 radix=3 digit=0
# OEIS-Other: A000004 radix=10 digit=0

sub oeis_anum {
  my ($self) = @_;
  my $radix = $self->{'radix'};
  my $digit = $self->{'digit'};
  if ($digit == -1) {
    $digit = $radix-1;
  } elsif ($digit >= $radix || $digit == 0) {
    return 'A000004'; # all zeros,
  }
  return $oeis_anum[$radix]->[$digit];
}

sub ith {
  my ($self, $i) = @_;
  $i = abs($i);
  if (_is_infinite($i)) {
    return $i;  # don't loop forever if $i is +infinity
  }

  my $radix = $self->{'radix'};
  my $digit = $self->{'digit'};
  if ($digit == -1) { $digit = $radix - 1; }

  my $count = 0;
    while ($i) {
      if (($i % $radix) == $digit) {
        $count++;
      } else {
        $count = 0;
      }
      $i = int($i/$radix);
    }
  return $count;
}

sub pred {
  my ($self, $value) = @_;
  return ($value >= 0 && $value == int($value));
}

1;
__END__