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/*
* Copyright 2008-2012 NVIDIA Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*! \file extrema.h
* \brief Functions for computing computing extremal values
*/
#pragma once
#include <thrust/detail/config.h>
#include <thrust/detail/dispatchable.h>
#include <thrust/pair.h>
namespace thrust
{
template<typename System, typename ForwardIterator>
ForwardIterator min_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last);
template<typename System, typename ForwardIterator, typename BinaryPredicate>
ForwardIterator min_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last, BinaryPredicate comp);
template<typename System, typename ForwardIterator>
ForwardIterator max_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last);
template<typename System, typename ForwardIterator, typename BinaryPredicate>
ForwardIterator max_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last, BinaryPredicate comp);
template<typename System, typename ForwardIterator>
thrust::pair<ForwardIterator,ForwardIterator> minmax_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last);
template<typename System, typename ForwardIterator, typename BinaryPredicate>
thrust::pair<ForwardIterator,ForwardIterator> minmax_element(thrust::detail::dispatchable_base<System> &system, ForwardIterator first, ForwardIterator last, BinaryPredicate comp);
/*! This version of \p min returns the smaller of two values, given a comparison operation.
* \param lhs The first value to compare.
* \param rhs The second value to compare.
* \param comp A comparison operation.
* \return The smaller element.
*
* \tparam T is convertible to \p BinaryPredicate's first argument type and to its second argument type.
* \tparam BinaryPredicate is a model of <a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">BinaryPredicate</a>.
*
* The following code snippet demonstrates how to use \p min to compute the smaller of two
* key-value objects.
*
* \code
* #include <thrust/extrema.h>
* ...
* struct key_value
* {
* int key;
* int value;
* };
*
* struct compare_key_value
* {
* __host__ __device__
* bool operator()(key_value lhs, key_value rhs)
* {
* return lhs.key < rhs.key;
* }
* };
*
* ...
* key_value a = {13, 0};
* key_value b = { 7, 1);
*
* key_value smaller = thrust::min(a, b, compare_key_value());
*
* // smaller is {7, 1}
* \endcode
*
* \note Returns the first argument when the arguments are equivalent.
* \see max
*/
template<typename T, typename BinaryPredicate>
__host__ __device__
T min THRUST_PREVENT_MACRO_SUBSTITUTION (const T &lhs, const T &rhs, BinaryPredicate comp);
/*! This version of \p min returns the smaller of two values.
* \param lhs The first value to compare.
* \param rhs The second value to compare.
* \return The smaller element.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* The following code snippet demonstrates how to use \p min to compute the smaller of two
* integers.
*
* \code
* #include <thrust/extrema.h>
* ...
* int a = 13;
* int b = 7;
*
* int smaller = thrust::min(a, b);
*
* // smaller is 7
* \endcode
*
* \note Returns the first argument when the arguments are equivalent.
* \see max
*/
template<typename T>
__host__ __device__
T min THRUST_PREVENT_MACRO_SUBSTITUTION (const T &lhs, const T &rhs);
/*! This version of \p max returns the larger of two values, given a comparison operation.
* \param lhs The first value to compare.
* \param rhs The second value to compare.
* \param comp A comparison operation.
* \return The larger element.
*
* \tparam T is convertible to \p BinaryPredicate's first argument type and to its second argument type.
* \tparam BinaryPredicate is a model of <a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">BinaryPredicate</a>.
*
* The following code snippet demonstrates how to use \p max to compute the larger of two
* key-value objects.
*
* \code
* #include <thrust/extrema.h>
* ...
* struct key_value
* {
* int key;
* int value;
* };
*
* struct compare_key_value
* {
* __host__ __device__
* bool operator()(key_value lhs, key_value rhs)
* {
* return lhs.key < rhs.key;
* }
* };
*
* ...
* key_value a = {13, 0};
* key_value b = { 7, 1);
*
* key_value larger = thrust::max(a, b, compare_key_value());
*
* // larger is {13, 0}
* \endcode
*
* \note Returns the first argument when the arguments are equivalent.
* \see min
*/
template<typename T, typename BinaryPredicate>
__host__ __device__
T max THRUST_PREVENT_MACRO_SUBSTITUTION (const T &lhs, const T &rhs, BinaryPredicate comp);
/*! This version of \p max returns the larger of two values.
* \param lhs The first value to compare.
* \param rhs The second value to compare.
* \return The larger element.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* The following code snippet demonstrates how to use \p max to compute the larger of two
* integers.
*
* \code
* #include <thrust/extrema.h>
* ...
* int a = 13;
* int b = 7;
*
* int larger = thrust::min(a, b);
*
* // larger is 13
* \endcode
*
* \note Returns the first argument when the arguments are equivalent.
* \see min
*/
template<typename T>
__host__ __device__
T max THRUST_PREVENT_MACRO_SUBSTITUTION (const T &lhs, const T &rhs);
/*! \addtogroup reductions
* \{
* \addtogroup extrema
* \ingroup reductions
* \{
*/
/*! \p min_element finds the smallest element in the range <tt>[first, last)</tt>.
* It returns the first iterator \c i in <tt>[first, last)</tt>
* such that no other iterator in <tt>[first, last)</tt> points to a value smaller
* than \c *i. The return value is \p last if and only if <tt>[first, last)</tt> is an
* empty range.
*
* The two versions of \p min_element differ in how they define whether one element is
* less than another. This version compares objects using \c operator<. Specifically,
* this version of \p min_element returns the first iterator \c i in <tt>[first, last)</tt>
* such that, for every iterator \c j in <tt>[first, last)</tt>, <tt>*j < *i</tt> is
* \c false.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \return An iterator pointing to the smallest element of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator">Forward Iterator</a>,
* and \c ForwardIterator's \c value_type is a model of
* <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \code
* #include <thrust/extrema.h>
* ...
* int data[6] = {1, 0, 2, 2, 1, 3};
* int *result = thrust::min_element(data, data + 6);
*
* // result is data + 1
* // *result is 0
* \endcode
*
* \see http://www.sgi.com/tech/stl/min_element.html
*/
template <typename ForwardIterator>
ForwardIterator min_element(ForwardIterator first, ForwardIterator last);
/*! \p min_element finds the smallest element in the range <tt>[first, last)</tt>.
* It returns the first iterator \c i in <tt>[first, last)</tt>
* such that no other iterator in <tt>[first, last)</tt> points to a value smaller
* than \c *i. The return value is \p last if and only if <tt>[first, last)</tt> is an
* empty range.
*
* The two versions of \p min_element differ in how they define whether one element is
* less than another. This version compares objects using a function object \p comp.
* Specifically, this version of \p min_element returns the first iterator \c i in <tt>[first, last)</tt>
* such that, for every iterator \c j in <tt>[first, last)</tt>, <tt>comp(*j, *i)</tt> is
* \c false.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \param comp A binary predicate used for comparison.
* \return An iterator pointing to the smallest element of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator">Forward Iterator</a>,
* and \p ForwardIterator's \c value_type is convertible to both \p comp's
* \c first_argument_type and \c second_argument_type.
* \tparam BinaryPredicate is a model of <a href="http://www.sgi.com/tech/stl/BinaryPredicate">Binary Predicate</a>.
*
* The following code snippet demonstrates how to use \p min_element to find the smallest element
* of a collection of key-value pairs.
*
* \code
* #include <thrust/extrema.h>
*
* struct key_value
* {
* int key;
* int value;
* };
*
* struct compare_key_value
* {
* __host__ __device__
* bool operator()(key_value lhs, key_value rhs)
* {
* return lhs.key < rhs.key;
* }
* };
*
* ...
* key_value data[4] = { {4,5}, {0,7}, {2,3}, {6,1} };
*
* key_value *smallest = thrust::min_element(data, data + 4, compare_key_value());
*
* // smallest == data + 1
* // *smallest == {0,7}
* \endcode
*
* \see http://www.sgi.com/tech/stl/min_element.html
*/
template <typename ForwardIterator, typename BinaryPredicate>
ForwardIterator min_element(ForwardIterator first, ForwardIterator last,
BinaryPredicate comp);
/*! \p max_element finds the largest element in the range <tt>[first, last)</tt>.
* It returns the first iterator \c i in <tt>[first, last)</tt>
* such that no other iterator in <tt>[first, last)</tt> points to a value larger
* than \c *i. The return value is \p last if and only if <tt>[first, last)</tt> is an
* empty range.
*
* The two versions of \p max_element differ in how they define whether one element is
* greater than another. This version compares objects using \c operator<. Specifically,
* this version of \p max_element returns the first iterator \c i in <tt>[first, last)</tt>
* such that, for every iterator \c j in <tt>[first, last)</tt>, <tt>*i < *j</tt> is
* \c false.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \return An iterator pointing to the largest element of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>,
* and \c ForwardIterator's \c value_type is a model of
* <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \code
* #include <thrust/extrema.h>
* ...
* int data[6] = {1, 0, 2, 2, 1, 3};
* int *result = thrust::max_element(data, data + 6);
*
* // *result == 3
* \endcode
*
* \see http://www.sgi.com/tech/stl/max_element.html
*/
template <typename ForwardIterator>
ForwardIterator max_element(ForwardIterator first, ForwardIterator last);
/*! \p max_element finds the largest element in the range <tt>[first, last)</tt>.
* It returns the first iterator \c i in <tt>[first, last)</tt>
* such that no other iterator in <tt>[first, last)</tt> points to a value larger
* than \c *i. The return value is \p last if and only if <tt>[first, last)</tt> is an
* empty range.
*
* The two versions of \p max_element differ in how they define whether one element is
* less than another. This version compares objects using a function object \p comp.
* Specifically, this version of \p max_element returns the first iterator \c i in <tt>[first, last)</tt>
* such that, for every iterator \c j in <tt>[first, last)</tt>, <tt>comp(*i, *j)</tt> is
* \c false.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \param comp A binary predicate used for comparison.
* \return An iterator pointing to the largest element of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>,
* and \p ForwardIterator's \c value_type is convertible to both \p comp's
* \c first_argument_type and \c second_argument_type.
* \tparam BinaryPredicate is a model of <a href="http://www.sgi.com/tech/stl/BinaryPredicate.html">Binary Predicate</a>.
*
* The following code snippet demonstrates how to use \p max_element to find the largest element
* of a collection of key-value pairs.
*
* \code
* #include <thrust/extrema.h>
*
* struct key_value
* {
* int key;
* int value;
* };
*
* struct compare_key_value
* {
* __host__ __device__
* bool operator()(key_value lhs, key_value rhs)
* {
* return lhs.key < rhs.key;
* }
* };
*
* ...
* key_value data[4] = { {4,5}, {0,7}, {2,3}, {6,1} };
*
* key_value *largest = thrust::max_element(data, data + 4, compare_key_value());
*
* // largest == data + 3
* // *largest == {6,1}
* \endcode
*
* \see http://www.sgi.com/tech/stl/max_element.html
*/
template <typename ForwardIterator, typename BinaryPredicate>
ForwardIterator max_element(ForwardIterator first, ForwardIterator last,
BinaryPredicate comp);
/*! \p minmax_element finds the smallest and largest elements in the range <tt>[first, last)</tt>.
* It returns a pair of iterators <tt>(imin, imax)</tt> where \c imin is the same iterator
* returned by \p min_element and \c imax is the same iterator returned by \p max_element.
* This function is potentially more efficient than separate calls to \p min_element and \p max_element.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \return A pair of iterator pointing to the smallest and largest elements of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator.html">Forward Iterator</a>,
* and \c ForwardIterator's \c value_type is a model of
* <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \code
* #include <thrust/extrema.h>
* ...
* int data[6] = {1, 0, 2, 2, 1, 3};
* thrust::pair<int *, int *> result = thrust::minmax_element(data, data + 6);
*
* // result.first is data + 1
* // result.second is data + 5
* // *result.first is 0
* // *result.second is 3
* \endcode
*
* \see min_element
* \see max_element
* \see http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1840.pdf
*/
template <typename ForwardIterator>
thrust::pair<ForwardIterator,ForwardIterator> minmax_element(ForwardIterator first,
ForwardIterator last);
/*! \p minmax_element finds the smallest and largest elements in the range <tt>[first, last)</tt>.
* It returns a pair of iterators <tt>(imin, imax)</tt> where \c imin is the same iterator
* returned by \p min_element and \c imax is the same iterator returned by \p max_element.
* This function is potentially more efficient than separate calls to \p min_element and \p max_element.
*
* \param first The beginning of the sequence.
* \param last The end of the sequence.
* \param comp A binary predicate used for comparison.
* \return A pair of iterator pointing to the smallest and largest elements of the range <tt>[first, last)</tt>,
* if it is not an empty range; \p last, otherwise.
*
* \tparam ForwardIterator is a model of <a href="http://www.sgi.com/tech/stl/ForwardIterator">Forward Iterator</a>,
* and \p ForwardIterator's \c value_type is convertible to both \p comp's
* \c first_argument_type and \c second_argument_type.
* \tparam BinaryPredicate is a model of <a href="http://www.sgi.com/tech/stl/BinaryPredicate">Binary Predicate</a>.
*
* The following code snippet demonstrates how to use \p minmax_element to find the smallest and largest elements
* of a collection of key-value pairs.
*
* \code
* #include <thrust/extrema.h>
* #include <thrust/pair.h>
*
* struct key_value
* {
* int key;
* int value;
* };
*
* struct compare_key_value
* {
* __host__ __device__
* bool operator()(key_value lhs, key_value rhs)
* {
* return lhs.key < rhs.key;
* }
* };
*
* ...
* key_value data[4] = { {4,5}, {0,7}, {2,3}, {6,1} };
*
* thrust::pair<key_value*,key_value*> extrema = thrust::minmax_element(data, data + 4, compare_key_value());
*
* // extrema.first == data + 1
* // *extrema.first == {0,7}
* // extrema.second == data + 3
* // *extrema.second == {6,1}
* \endcode
*
* \see min_element
* \see max_element
* \see http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1840.pdf
*/
template <typename ForwardIterator, typename BinaryPredicate>
thrust::pair<ForwardIterator,ForwardIterator> minmax_element(ForwardIterator first,
ForwardIterator last,
BinaryPredicate comp);
/*! \} // end extrema
* \} // end reductions
*/
} // end thrust
#include <thrust/detail/extrema.inl>
#include <thrust/detail/minmax.h>
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