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Math::Prime::Util::PriUsereContributed PerlMath::Prime::Util::PrimeIterator(3)

NAME
       Math::Prime::Util::PrimeIterator	- An object iterator for primes

VERSION
       Version 0.73

SYNOPSIS
	 use Math::Prime::Util::PrimeIterator;
	 my $it	= Math::Prime::Util::PrimeIterator->new();

	 # Simple use: return current value and	move forward.
	 my $sum = 0;  $sum += $it->iterate() for 1..10000;

	 # Methods
	 my $v = $it->value();	   # Return current value
	 $it->next();		   # Move to next prime	(returns self)
	 $it->prev();		   # Move to prev prime	(returns self)
	 $v = $it->iterate();	   # Returns current value; moves to next prime
	 $it->rewind();		   # Resets position to	2
	 $it->rewind($n);	   # Resets position to	next_prime($n-1)

	 # Methods similar to Math::NumSeq, do not change iterator
	 $it->tell_i();		   # Returns the index of the current position
	 $it->pred($n);		   # Returns true if $n	is prime
	 $it->ith($i);		   # Returns the $ith prime
	 $it->value_to_i($n);	   # Returns the index of the first prime >= $n
	 $it->value_to_i_estimate($n);	# Approx index of value	$n

	 # Methods similar to Math::NumSeq, changes iterator
	 $it->seek_to_i($i);	   # Resets position to	the $ith prime
	 $it->seek_to_value($i);   # Resets position to	next_prime($i-1)

DESCRIPTION
       An iterator over	the primes.  "new" returns an iterator object and
       takes an	optional starting position (the	initial	value will be the
       least prime greater than	or equal to the	argument).  BigInt objects
       will be returned	if the value overflows a Perl unsigned integer value.

METHODS
   new
       Creates an iterator object with initial value of	2.  If an argument is
       given, the initial value	will be	the least prime	greater	than or	equal
       to the argument.

   value
       Returns the value at the	current	position.  Will	always be a prime.  If
       the value is greater than ~0, it	will be	a Math::BigInt object.

   next
       Moves the current position to the next prime.  Returns self so calls
       can be chained.

   prev
       Moves the current position to the previous prime, unless	the current
       value is	2, in which case the value remains 2.  Returns self so calls
       can be chained.

   iterate
       Returns the value at the	current	position and also moves	the position
       to the next prime.

   rewind
       Resets the current position to either 2 or, if given an integer
       argument, the least prime not less than the argument.

   peek
       Returns the value at the	next position without moving the iterator.

   tell_i
       Returns the index of the	current	position, starting at 1	(corresponding
       to the value 2).	 The iterator is unchanged after this call.

   pred
       Returns true if the argument is a prime,	false otherwise.  The iterator
       is unchanged after this call.

   ith
       Returns the i'th	prime, where the first prime is	2.  The	iterator is
       unchanged after this call.

   value_to_i_estimate
       Returns an estimate of the index	corresponding to the argument.	That
       is, given a value "n", we expect	a prime	approximately equal to "n" to
       occur at	this index.

       The estimate is performed using "prime_count_approx" in
       Math::Prime::Util, which	uses the estimates of Dusart 2010 (or better
       for small values).

   value_to_i
       If the argument is prime, returns the corresponding index, such that:

	 ith( value_to_i( $n ) ) == $n

       Returns "undef" if the argument is not prime.

   value_to_i_floor
   value_to_i_ceil
       Returns the index corresponding to the first prime less than or equal
       to the argument,	or greater than	or equal to the	argument,
       respectively.

   seek_to_i
       Resets the position to the prime	corresponding to the given index.

   seek_to_value
       An alias	for "rewind".

   i_start =head2 description =head2 values_min	=head2 values_max =head2
       oeis_anum
       Methods to match	Math::NumSeq::Primes.

SEE ALSO
       Math::Prime::Util

       "forprimes" in Math::Prime::Util

       "prime_iterator"	in Math::Prime::Util

       "prime_iterator_object" in Math::Prime::Util

       Math::Prime::Util::PrimeArray

       Math::NumSeq::Primes

       List::Gen

AUTHORS
       Dana Jacobsen <dana@acm.org>

COPYRIGHT
       Copyright 2013 by Dana Jacobsen <dana@acm.org>

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

perl v5.32.1			  2018-11-1Math::Prime::Util::PrimeIterator(3)

NAME | VERSION | SYNOPSIS | DESCRIPTION | METHODS | SEE ALSO | AUTHORS | COPYRIGHT

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