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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 functional.h
* \brief Function objects and tools for manipulating them
*/
#pragma once
#include <thrust/detail/config.h>
#include <functional>
#include <thrust/detail/functional/placeholder.h>
namespace thrust
{
/*! \addtogroup function_objects Function Objects
*/
template<typename Operation> struct unary_traits;
template<typename Operation> struct binary_traits;
/*! \addtogroup function_object_adaptors Function Object Adaptors
* \ingroup function_objects
* \{
*/
/*! \p unary_function is an empty base class: it contains no member functions
* or member variables, but only type information. The only reason it exists
* is to make it more convenient to define types that are models of the
* concept Adaptable Unary Function. Specifically, any model of Adaptable
* Unary Function must define nested \c typedefs. Those \c typedefs are
* provided by the base class \p unary_function.
*
* The following code snippet demonstrates how to construct an
* Adaptable Unary Function using \p unary_function.
*
* \code
* struct sine : public thrust::unary_function<float,float>
* {
* __host__ __device__
* float operator()(float x) { return sinf(x); }
* };
* \endcode
*
* \note unary_function is currently redundant with the C++ STL type
* \c std::unary_function. We reserve it here for potential additional
* functionality at a later date.
*
* \see http://www.sgi.com/tech/stl/unary_function.html
* \see binary_function
*/
template<typename Argument,
typename Result>
struct unary_function
: public std::unary_function<Argument, Result>
{
}; // end unary_function
/*! \p binary_function is an empty base class: it contains no member functions
* or member variables, but only type information. The only reason it exists
* is to make it more convenient to define types that are models of the
* concept Adaptable Binary Function. Specifically, any model of Adaptable
* Binary Function must define nested \c typedefs. Those \c typedefs are
* provided by the base class \p binary_function.
*
* The following code snippet demonstrates how to construct an
* Adaptable Binary Function using \p binary_function.
*
* \code
* struct exponentiate : public thrust::binary_function<float,float,float>
* {
* __host__ __device__
* float operator()(float x, float y) { return powf(x,y); }
* };
* \endcode
*
* \note binary_function is currently redundant with the C++ STL type
* \c std::binary_function. We reserve it here for potential additional
* functionality at a later date.
*
* \see http://www.sgi.com/tech/stl/binary_function.html
* \see unary_function
*/
template<typename Argument1,
typename Argument2,
typename Result>
struct binary_function
: public std::binary_function<Argument1, Argument2, Result>
{
}; // end binary_function
/*! \}
*/
/*! \addtogroup predefined_function_objects Predefined Function Objects
* \ingroup function_objects
*/
/*! \addtogroup arithmetic_operations Arithmetic Operations
* \ingroup predefined_function_objects
* \{
*/
/*! \p plus is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>plus<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x+y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x+y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>plus</tt> to sum two
* device_vectors of \c floats.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
* thrust::device_vector<float> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 75);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::plus<float>());
* // V3 is now {76, 77, 78, ..., 1075}
* \endcode
*
* \see http://www.sgi.com/tech/stl/plus.html
* \see binary_function
*/
template<typename T>
struct plus : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs + rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs + rhs;}
}; // end plus
/*! \p minus is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>minus<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x-y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x-y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>minus</tt> to subtract
* a device_vector of \c floats from another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
* thrust::device_vector<float> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 75);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::minus<float>());
* // V3 is now {-74, -75, -76, ..., -925}
* \endcode
*
* \see http://www.sgi.com/tech/stl/minus.html
* \see binary_function
*/
template<typename T>
struct minus : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs - rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs - rhs;}
}; // end minus
/*! \p multiplies is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>minus<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x*y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x*y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>multiplies</tt> to multiply
* two device_vectors of \c floats.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
* thrust::device_vector<float> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 75);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::multiplies<float>());
* // V3 is now {75, 150, 225, ..., 75000}
* \endcode
*
* \see http://www.sgi.com/tech/stl/multiplies.html
* \see binary_function
*/
template<typename T>
struct multiplies : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs * rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs * rhs;}
}; // end multiplies
/*! \p divides is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>divides<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x/y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x/y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>divides</tt> to divide
* one device_vectors of \c floats by another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
* thrust::device_vector<float> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 75);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::divides<float>());
* // V3 is now {1/75, 2/75, 3/75, ..., 1000/75}
* \endcode
*
* \see http://www.sgi.com/tech/stl/divides.html
* \see binary_function
*/
template<typename T>
struct divides : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs / rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs / rhs;}
}; // end divides
/*! \p modulus is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>divides<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x%y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x%y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>modulus</tt> to take
* the modulus of one device_vectors of \c floats by another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
* thrust::device_vector<float> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 75);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::modulus<int>());
* // V3 is now {1%75, 2%75, 3%75, ..., 1000%75}
* \endcode
*
* \see http://www.sgi.com/tech/stl/modulus.html
* \see binary_function
*/
template<typename T>
struct modulus : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs % rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs % rhs;}
}; // end modulus
/*! \p negate is a function object. Specifically, it is an Adaptable Unary Function.
* If \c f is an object of class <tt>negate<T></tt>, and \c x is an object
* of class \c T, then <tt>f(x)</tt> returns <tt>-x</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x is an object of type \p T, then <tt>-x</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>negate</tt> to negate
* the element of a device_vector of \c floats.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<float> V1(N);
* thrust::device_vector<float> V2(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(),
* thrust::negate<float>());
* // V2 is now {-1, -2, -3, ..., -1000}
* \endcode
*
* \see http://www.sgi.com/tech/stl/negate.html
* \see unary_function
*/
template<typename T>
struct negate : public unary_function<T,T>
{
/*! Function call operator. The return value is <tt>-x</tt>.
*/
__host__ __device__ T operator()(const T &x) const {return -x;}
}; // end negate
/*! \}
*/
/*! \addtogroup comparison_operations Comparison Operations
* \ingroup predefined_function_objects
* \{
*/
/*! \p equal_to is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>equal_to<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x == y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/EqualityComparable.html">Equality Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/equal_to.html
* \see binary_function
*/
template<typename T>
struct equal_to : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs == rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs == rhs;}
}; // end equal_to
/*! \p not_equal_to is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>not_equal_to<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x != y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/EqualityComparable.html">Equality Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/not_equal_to.html
* \see binary_function
*/
template<typename T>
struct not_equal_to : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs != rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs != rhs;}
}; // end not_equal_to
/*! \p greater is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>greater<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x > y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/greater.html
* \see binary_function
*/
template<typename T>
struct greater : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs > rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs > rhs;}
}; // end greater
/*! \p less is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>less<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x < y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/less.html
* \see binary_function
*/
template<typename T>
struct less : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs < rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs < rhs;}
}; // end less
/*! \p greater_equal is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>greater_equal<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x >= y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/greater_equal.html
* \see binary_function
*/
template<typename T>
struct greater_equal : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs >= rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs >= rhs;}
}; // end greater_equal
/*! \p less_equal is a function object. Specifically, it is an Adaptable Binary
* Predicate, which means it is a function object that tests the truth or falsehood
* of some condition. If \c f is an object of class <tt>less_equal<T></tt> and \c x
* and \c y are objects of class \c T, then <tt>f(x,y)</tt> returns \c true if
* <tt>x <= y</tt> and \c false otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* \see http://www.sgi.com/tech/stl/less_equal.html
* \see binary_function
*/
template<typename T>
struct less_equal : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs <= rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs <= rhs;}
}; // end less_equal
/*! \}
*/
/*! \addtogroup logical_operations Logical Operations
* \ingroup predefined_function_objects
* \{
*/
/*! \p logical_and is a function object. Specifically, it is an Adaptable Binary Predicate,
* which means it is a function object that tests the truth or falsehood of some condition.
* If \c f is an object of class <tt>logical_and<T></tt> and \c x and \c y are objects of
* class \c T (where \c T is convertible to \c bool) then <tt>f(x,y)</tt> returns \c true
* if and only if both \c x and \c y are \c true.
*
* \tparam T must be convertible to \c bool.
*
* \see http://www.sgi.com/tech/stl/logical_and.html
* \see binary_function
*/
template<typename T>
struct logical_and : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs && rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs && rhs;}
}; // end logical_and
/*! \p logical_or is a function object. Specifically, it is an Adaptable Binary Predicate,
* which means it is a function object that tests the truth or falsehood of some condition.
* If \c f is an object of class <tt>logical_or<T></tt> and \c x and \c y are objects of
* class \c T (where \c T is convertible to \c bool) then <tt>f(x,y)</tt> returns \c true
* if and only if either \c x or \c y are \c true.
*
* \tparam T must be convertible to \c bool.
*
* \see http://www.sgi.com/tech/stl/logical_or.html
* \see binary_function
*/
template<typename T>
struct logical_or : public binary_function<T,T,bool>
{
/*! Function call operator. The return value is <tt>lhs || rhs</tt>.
*/
__host__ __device__ bool operator()(const T &lhs, const T &rhs) const {return lhs || rhs;}
}; // end logical_or
/*! \p logical_not is a function object. Specifically, it is an Adaptable Predicate,
* which means it is a function object that tests the truth or falsehood of some condition.
* If \c f is an object of class <tt>logical_not<T></tt> and \c x is an object of
* class \c T (where \c T is convertible to \c bool) then <tt>f(x)</tt> returns \c true
* if and only if \c x is \c false.
*
* \tparam T must be convertible to \c bool.
*
* The following code snippet demonstrates how to use \p logical_not to transform
* a device_vector of \c bools into its logical complement.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/transform.h>
* #include <thrust/functional.h>
* ...
* thrust::device_vector<bool> V;
* ...
* thrust::transform(V.begin(), V.end(), V.begin(), thrust::logical_not<bool>());
* // The elements of V are now the logical complement of what they were prior
* \endcode
*
* \see http://www.sgi.com/tech/stl/logical_not.html
* \see unary_function
*/
template<typename T>
struct logical_not : public unary_function<T,bool>
{
/*! Function call operator. The return value is <tt>!x</tt>.
*/
__host__ __device__ bool operator()(const T &x) const {return !x;}
}; // end logical_not
/*! \}
*/
/*! \addtogroup bitwise_operations Bitwise Operations
* \ingroup predefined_function_objects
* \{
*/
/*! \p bit_and is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>bit_and<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x&y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x&y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>bit_and</tt> to take
* the bitwise AND of one device_vector of \c ints by another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<int> V1(N);
* thrust::device_vector<int> V2(N);
* thrust::device_vector<int> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 13);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::bit_and<int>());
* // V3 is now {1&13, 2&13, 3&13, ..., 1000%13}
* \endcode
*
* \see binary_function
*/
template<typename T>
struct bit_and : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs & rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs & rhs;}
}; // end bit_and
/*! \p bit_or is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>bit_and<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x|y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x|y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>bit_or</tt> to take
* the bitwise OR of one device_vector of \c ints by another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<int> V1(N);
* thrust::device_vector<int> V2(N);
* thrust::device_vector<int> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 13);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::bit_or<int>());
* // V3 is now {1|13, 2|13, 3|13, ..., 1000|13}
* \endcode
*
* \see binary_function
*/
template<typename T>
struct bit_or : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs | rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs | rhs;}
}; // end bit_or
/*! \p bit_xor is a function object. Specifically, it is an Adaptable Binary Function.
* If \c f is an object of class <tt>bit_and<T></tt>, and \c x and \c y are objects
* of class \c T, then <tt>f(x,y)</tt> returns <tt>x^y</tt>.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/Assignable.html">Assignable</a>,
* and if \c x and \c y are objects of type \p T, then <tt>x^y</tt> must be defined and must have a return type that is convertible to \c T.
*
* The following code snippet demonstrates how to use <tt>bit_xor</tt> to take
* the bitwise XOR of one device_vector of \c ints by another.
*
* \code
* #include <thrust/device_vector.h>
* #include <thrust/functional.h>
* #include <thrust/sequence.h>
* #include <thrust/fill.h>
* #include <thrust/transform.h>
* ...
* const int N = 1000;
* thrust::device_vector<int> V1(N);
* thrust::device_vector<int> V2(N);
* thrust::device_vector<int> V3(N);
*
* thrust::sequence(V1.begin(), V1.end(), 1);
* thrust::fill(V2.begin(), V2.end(), 13);
*
* thrust::transform(V1.begin(), V1.end(), V2.begin(), V3.begin(),
* thrust::bit_xor<int>());
* // V3 is now {1^13, 2^13, 3^13, ..., 1000^13}
* \endcode
*
* \see binary_function
*/
template<typename T>
struct bit_xor : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs ^ rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs ^ rhs;}
}; // end bit_xor
/*! \}
*/
/*! \addtogroup generalized_identity_operations Generalized Identity Operations
* \ingroup predefined_function_objects
* \{
*/
/*! \p identity is a Unary Function that represents the identity function: it takes
* a single argument \c x, and returns \c x.
*
* \tparam T No requirements on \p T.
*
* The following code snippet demonstrates that \p identity returns its
* argument.
*
* \code
* #include <thrust/functional.h>
* #include <assert.h>
* ...
* int x = 137;
* thrust::identity<int> id;
* assert(x == id(x));
* \endcode
*
* \see http://www.sgi.com/tech/stl/identity.html
* \see unary_function
*/
template<typename T>
struct identity : public unary_function<T,T>
{
/*! Function call operator. The return value is <tt>x</tt>.
*/
__host__ __device__ const T &operator()(const T &x) const {return x;}
}; // end identity
/*! \p maximum is a function object that takes two arguments and returns the greater
* of the two. Specifically, it is an Adaptable Binary Function. If \c f is an
* object of class <tt>maximum<T></tt> and \c x and \c y are objects of class \c T
* <tt>f(x,y)</tt> returns \c x if <tt>x > y</tt> and \c y, otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* The following code snippet demonstrates that \p maximum returns its
* greater argument.
*
* \code
* #include <thrust/functional.h>
* #include <assert.h>
* ...
* int x = 137;
* int y = -137;
* thrust::maximum<int> mx;
* assert(x == mx(x,y));
* \endcode
*
* \see minimum
* \see min
* \see binary_function
*/
template<typename T>
struct maximum : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>rhs < lhs ? lhs : rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs < rhs ? rhs : lhs;}
}; // end maximum
/*! \p minimum is a function object that takes two arguments and returns the lesser
* of the two. Specifically, it is an Adaptable Binary Function. If \c f is an
* object of class <tt>minimum<T></tt> and \c x and \c y are objects of class \c T
* <tt>f(x,y)</tt> returns \c x if <tt>x < y</tt> and \c y, otherwise.
*
* \tparam T is a model of <a href="http://www.sgi.com/tech/stl/LessThanComparable.html">LessThan Comparable</a>.
*
* The following code snippet demonstrates that \p minimum returns its
* lesser argument.
*
* \code
* #include <thrust/functional.h>
* #include <assert.h>
* ...
* int x = 137;
* int y = -137;
* thrust::minimum<int> mn;
* assert(y == mn(x,y));
* \endcode
*
* \see maximum
* \see max
* \see binary_function
*/
template<typename T>
struct minimum : public binary_function<T,T,T>
{
/*! Function call operator. The return value is <tt>lhs < rhs ? lhs : rhs</tt>.
*/
__host__ __device__ T operator()(const T &lhs, const T &rhs) const {return lhs < rhs ? lhs : rhs;}
}; // end minimum
/*! \p project1st is a function object that takes two arguments and returns
* its first argument; the second argument is unused. It is essentially a
* generalization of identity to the case of a Binary Function.
*
* \code
* #include <thrust/functional.h>
* #include <assert.h>
* ...
* int x = 137;
* int y = -137;
* thrust::project1st<int> pj1;
* assert(x == pj1(x,y));
* \endcode
*
* \see identity
* \see project2nd
* \see binary_function
*/
template<typename T1, typename T2>
struct project1st : public binary_function<T1,T2,T1>
{
/*! Function call operator. The return value is <tt>lhs</tt>.
*/
__host__ __device__ const T1 &operator()(const T1 &lhs, const T2 &rhs) const {return lhs;}
}; // end project1st
/*! \p project2nd is a function object that takes two arguments and returns
* its second argument; the first argument is unused. It is essentially a
* generalization of identity to the case of a Binary Function.
*
* \code
* #include <thrust/functional.h>
* #include <assert.h>
* ...
* int x = 137;
* int y = -137;
* thrust::project2nd<int> pj2;
* assert(y == pj2(x,y));
* \endcode
*
* \see identity
* \see project1st
* \see binary_function
*/
template<typename T1, typename T2>
struct project2nd : public binary_function<T1,T2,T2>
{
/*! Function call operator. The return value is <tt>rhs</tt>.
*/
__host__ __device__ const T2 &operator()(const T1 &lhs, const T2 &rhs) const {return rhs;}
}; // end project2nd
/*! \}
*/
// odds and ends
/*! \addtogroup function_object_adaptors
* \{
*/
/*! \p unary_negate is a function object adaptor: it is an Adaptable Predicate
* that represents the logical negation of some other Adaptable Predicate.
* That is: if \c f is an object of class <tt>unary_negate<AdaptablePredicate></tt>,
* then there exists an object \c pred of class \c AdaptablePredicate such
* that <tt>f(x)</tt> always returns the same value as <tt>!pred(x)</tt>.
* There is rarely any reason to construct a <tt>unary_negate</tt> directly;
* it is almost always easier to use the helper function not1.
*
* \see http://www.sgi.com/tech/stl/unary_negate.html
* \see not1
*/
template<typename Predicate>
struct unary_negate
: public thrust::unary_function<typename Predicate::argument_type, bool>
{
/*! Constructor takes a \p Predicate object to negate.
* \param p The \p Predicate object to negate.
*/
__host__ __device__
explicit unary_negate(Predicate p) : pred(p){}
/*! Function call operator. The return value is <tt>!pred(x)</tt>.
*/
__host__ __device__
bool operator()(const typename Predicate::argument_type& x) { return !pred(x); }
/*! \cond */
Predicate pred;
/*! \endcond */
}; // end unary_negate
/*! \p not1 is a helper function to simplify the creation of Adaptable Predicates:
* it takes an Adaptable Predicate \p pred as an argument and returns a new Adaptable
* Predicate that represents the negation of \p pred. That is: if \c pred is an object
* of a type which models Adaptable Predicate, then the the type of the result
* \c npred of <tt>not1(pred)</tt> is also a model of Adaptable Predicate and
* <tt>npred(x)</tt> always returns the same value as <tt>!pred(x)</tt>.
*
* \param pred The Adaptable Predicate to negate.
* \return A new object, <tt>npred</tt> such that <tt>npred(x)</tt> always returns
* the same value as <tt>!pred(x)</tt>.
*
* \tparam Predicate is a model of <a href="http://www.sgi.com/tech/stl/AdaptablePredicate.html">Adaptable Predicate</a>.
*
* \see unary_negate
* \see not2
*/
template<typename Predicate>
__host__ __device__
unary_negate<Predicate> not1(const Predicate &pred);
/*! \p binary_negate is a function object adaptor: it is an Adaptable Binary
* Predicate that represents the logical negation of some other Adaptable
* Binary Predicate. That is: if \c f is an object of class <tt>binary_negate<AdaptablePredicate></tt>,
* then there exists an object \c pred of class \c AdaptableBinaryPredicate
* such that <tt>f(x,y)</tt> always returns the same value as <tt>!pred(x,y)</tt>.
* There is rarely any reason to construct a <tt>binary_negate</tt> directly;
* it is almost always easier to use the helper function not2.
*
* \see http://www.sgi.com/tech/stl/binary_negate.html
*/
template<typename Predicate>
struct binary_negate
: public thrust::binary_function<typename Predicate::first_argument_type,
typename Predicate::second_argument_type,
bool>
{
/*! Constructor takes a \p Predicate object to negate.
* \param p The \p Predicate object to negate.
*/
__host__ __device__
explicit binary_negate(Predicate p) : pred(p){}
/*! Function call operator. The return value is <tt>!pred(x,y)</tt>.
*/
__host__ __device__
bool operator()(const typename Predicate::first_argument_type& x, const typename Predicate::second_argument_type& y)
{
return !pred(x,y);
}
/*! \cond */
Predicate pred;
/*! \endcond */
}; // end binary_negate
/*! \p not2 is a helper function to simplify the creation of Adaptable Binary Predicates:
* it takes an Adaptable Binary Predicate \p pred as an argument and returns a new Adaptable
* Binary Predicate that represents the negation of \p pred. That is: if \c pred is an object
* of a type which models Adaptable Binary Predicate, then the the type of the result
* \c npred of <tt>not2(pred)</tt> is also a model of Adaptable Binary Predicate and
* <tt>npred(x,y)</tt> always returns the same value as <tt>!pred(x,y)</tt>.
*
* \param pred The Adaptable Binary Predicate to negate.
* \return A new object, <tt>npred</tt> such that <tt>npred(x,y)</tt> always returns
* the same value as <tt>!pred(x,y)</tt>.
*
* \tparam Binary Predicate is a model of <a href="http://www.sgi.com/tech/stl/AdaptableBinaryPredicate.html">Adaptable Binary Predicate</a>.
*
* \see binary_negate
* \see not1
*/
template<typename BinaryPredicate>
__host__ __device__
binary_negate<BinaryPredicate> not2(const BinaryPredicate &pred);
/*! \}
*/
namespace placeholders
{
static const thrust::detail::functional::placeholder<0>::type _1;
static const thrust::detail::functional::placeholder<1>::type _2;
static const thrust::detail::functional::placeholder<2>::type _3;
static const thrust::detail::functional::placeholder<3>::type _4;
static const thrust::detail::functional::placeholder<4>::type _5;
static const thrust::detail::functional::placeholder<5>::type _6;
static const thrust::detail::functional::placeholder<6>::type _7;
static const thrust::detail::functional::placeholder<7>::type _8;
static const thrust::detail::functional::placeholder<8>::type _9;
static const thrust::detail::functional::placeholder<9>::type _10;
} // end placeholders
} // end thrust
#include <thrust/detail/functional.inl>
#include <thrust/detail/functional/operators.h>