libs/range/doc/reference/algorithm/partial_sort.qbk
[/
Copyright 2010 Neil Groves
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:partial_sort partial_sort]
[heading Prototype]
``
template<class RandomAccessRange>
RandomAccessRange& partial_sort(
RandomAccessRange& rng,
typename range_iterator<RandomAccessRange>::type middle);
template<class RandomAccessRange>
const RandomAccessRange& partial_sort(
const RandomAccessRange& rng,
typename range_iterator<const RandomAccessRange>::type middle);
template<class RandomAccessRange>
RandomAccessRange& partial_sort(
RandomAccessRange& rng,
typename range_iterator<RandomAccessRange>::type middle,
BinaryPredicate sort_pred);
template<class RandomAccessRange>
const RandomAccessRange& partial_sort(
const RandomAccessRange& rng,
typename range_iterator<const RandomAccessRange>::type middle,
BinaryPredicate sort_pred);
``
[heading Description]
`partial_sort` rearranges the elements in `rng`. It places the smallest `distance(begin(rng), middle)` elements, sorted in ascending order, into the range `[begin(rng), middle)`. The remaining elements are placed in an unspecified order into `[middle, last)`.
The non-predicative versions of this function specify that one element is less than another by using `operator<()`. The predicate versions use the predicate instead.
[heading Definition]
Defined in the header file `boost/range/algorithm/partial_sort.hpp`
[heading Requirements]
[*For the non-predicate version:]
* `RandomAccessRange` is a model of the __random_access_range__ Concept.
* `RandomAccessRange` is mutable.
* `RandomAccessRange`'s value type is a model of the `LessThanComparableConcept`.
* The ordering relation on `RandomAccessRange`'s value type is a [*/strict weak ordering/], as defined in the `LessThanComparableConcept` requirements.
[*For the predicate version:]
* `RandomAccessRange` is a model of the __random_access_range__ Concept.
* `RandomAccessRange` is mutable.
* `BinaryPredicate` is a model of the `StrictWeakOrderingConcept`.
* `RandomAccessRange`'s value type is convertible to both of `BinaryPredicate`'s argument types.
[heading Complexity]
Approximately `distance(rng) * log(distance(begin(rng), middle))` comparisons.
[endsect]
