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#!/usr/bin/perl -w
# Copyright 2012, 2013 Kevin Ryde
# This file is part of Math-PlanePath.
#
# Math-PlanePath 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-PlanePath 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-PlanePath. If not, see <http://www.gnu.org/licenses/>.
use 5.004;
use strict;
use Test;
plan tests => 22;;
use lib 't';
use MyTestHelpers;
BEGIN { MyTestHelpers::nowarnings(); }
use Math::PlanePath::CoprimeColumns;
*_coprime = \&Math::PlanePath::CoprimeColumns::_coprime;
use Math::PlanePath::GcdRationals;
*_gcd = \&Math::PlanePath::GcdRationals::_gcd;
# uncomment this to run the ### lines
#use Smart::Comments;
require Math::PlanePath::ChanTree;
#------------------------------------------------------------------------------
# n_to_xy() reversal
{
require Math::PlanePath::GcdRationals;
foreach my $k (3 .. 7) {
foreach my $reduced (0, 1) {
my $path = Math::PlanePath::ChanTree->new (k => $k,
reduced => $reduced);
foreach my $n ($path->n_start .. 500) {
my ($x,$y) = $path->n_to_xy($n);
my $rev = $path->xy_to_n($x,$y);
if (! defined $rev || $rev != $n) {
$rev = (defined $rev ? $rev : 'undef');
die "k=$k reduced=$reduced n_to_xy($n)=$x,$y but reverse xy_to_n($x,$y) is rev=$rev";
}
if ($reduced) {
my $gcd = Math::PlanePath::GcdRationals::_gcd($x,$y);
if ($gcd > 1) {
die "k=$k reduced=$reduced n_to_xy($n)=$x,$y common factor $gcd";
}
}
}
ok ($k, $k);
}
}
}
#------------------------------------------------------------------------------
# block of points
eval 'use Math::BigInt try=>q{GMP}; 1'
|| eval 'use Math::BigInt; 1'
|| die;
{
my $size = 100;
foreach my $k (2 .. 7) {
foreach my $reduced (0, 1) {
my $path = Math::PlanePath::ChanTree->new (k => $k,
reduced => $reduced);
my %seen_n;
foreach my $x (1 .. $size) {
foreach my $y (1 .. $size) {
my $n = $path->xy_to_n(Math::BigInt->new($x),
Math::BigInt->new($y));
if ($reduced) {
if (is_reduced_xy($k,$x,$y)) {
if (! defined $n) {
die "k=$k reduced=$reduced xy_to_n($x,$y) is reduced point but n=undef";
}
} else {
if (defined $n) {
my $gcd = Math::PlanePath::GcdRationals::_gcd($x,$y);
die "k=$k reduced=$reduced xy_to_n($x,$y) is not reduced point (gcd=$gcd) but still have n=$n";
}
}
}
if (defined $n) {
if ($seen_n{$n}) {
die "k=$k xy_to_n($x,$y) is n=$n, but previously xy_to_n($seen_n{$n}) was n=$n";
}
$seen_n{$n} = "$x,$y";
}
}
}
ok ($k, $k);
}
}
}
sub is_reduced_xy {
my ($k, $x, $y) = @_;
if (! _coprime($x,$y)) {
return 0;
}
if (($k & 1) && is_both_odd($x,$y)) {
return 0;
}
return 1;
}
sub is_both_odd {
my ($x, $y) = @_;
return ($x % 2) && ($y % 2);
}
#------------------------------------------------------------------------------
exit 0;
|
