Pseudo-random numbers/Splitmix64: Difference between revisions

Content added Content deleted
(Added Perl)
m (→‎{{header|Perl}}: made splitmix64 a real class and added the "next_float" method)
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use Math::AnyNum qw(:overload);
use Math::AnyNum qw(:overload);


{ package splitmix64;
package splitmix64 {


our($state);
sub new {
my ($class, %opt) = @_;

sub new { $state = $_[2] }
bless {state => $opt{seed}}, $class;
}


sub next_int {
sub next_int {
my $next = $state = ($state + 0x9e3779b97f4a7c15) & (2**64 - 1);
my ($self) = @_;
my $next = $self->{state} = ($self->{state} + 0x9e3779b97f4a7c15) & (2**64 - 1);
$next = ($next ^ ($next >> 30)) * 0xbf58476d1ce4e5b9 & (2**64 - 1);
$next = ($next ^ ($next >> 30)) * 0xbf58476d1ce4e5b9 & (2**64 - 1);
$next = ($next ^ ($next >> 27)) * 0x94d049bb133111eb & (2**64 - 1);
$next = ($next ^ ($next >> 27)) * 0x94d049bb133111eb & (2**64 - 1);
($next ^ ($next >> 31)) & (2**64 - 1);
($next ^ ($next >> 31)) & (2**64 - 1);
}

sub next_float {
my ($self) = @_;
$self->next_int / 2**64;
}
}
}
}


say 'Seed: 1234567, first 5 values:';
say 'Seed: 1234567, first 5 values:';
my $rng = splitmix64->new( seed => 1234567 );
my $rng = splitmix64->new(seed => 1234567);
say splitmix64->next_int($rng) for 1..5;
say $rng->next_int for 1 .. 5;


my %h;
my %h;
say "\nSeed: 987654321, values histogram:";
say "\nSeed: 987654321, values histogram:";
$rng = splitmix64->new( seed => 987654321 );
$rng = splitmix64->new(seed => 987654321);
$h{int 5 * splitmix64->next_int($rng)/2**64}++ for 1..100_000;
$h{int 5 * $rng->next_float}++ for 1 .. 100_000;
say "$_ $h{$_}" for sort keys %h;</lang>
say "$_ $h{$_}" for sort keys %h;</lang>
{{out}}
{{out}}
Retrieved from "https://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64"