not_equal_to Struct
A binary predicate that tests whether a value of a specified type is not equal to another value of that type.
template<class Type>
struct not_equal_to : public binary_function<Type, Type, bool>
{
bool operator()(
const Type& _Left,
const Type& _Right
) const;
};
Parameters
_Left
The left operand of type Type in the equality to be tested._Right
The right operand of type Type in the equality to be tested.
Return Value
true if _Left does not equal _Right ; false if _Left equals _Right.
Remarks
The objects of type Type must be equality comparable. This requires that the operator!= defined on the set of objects satisfies the mathematical properties of an equivalence relation All the built-in numeric and pointer types satisfy this requirement.
Example
// functional_not_equal_to.cpp
// compile with: /EHsc
#include <vector>
#include <functional>
#include <algorithm>
#include <iostream>
using namespace std;
int main( )
{
vector <double> v1, v2, v3 (6);
vector <double>::iterator Iter1, Iter2, Iter3;
int i;
for ( i = 0 ; i <= 5 ; i+=2 )
{
v1.push_back( 2.0 *i );
v1.push_back( 2.0 * i + 1.0 );
}
int j;
for ( j = 0 ; j <= 5 ; j+=2 )
{
v2.push_back( - 2.0 * j );
v2.push_back( 2.0 * j + 1.0 );
}
cout << "The vector v1 = ( " ;
for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
cout << *Iter1 << " ";
cout << ")" << endl;
cout << "The vector v2 = ( " ;
for ( Iter2 = v2.begin( ) ; Iter2 != v2.end( ) ; Iter2++ )
cout << *Iter2 << " ";
cout << ")" << endl;
// Testing for the element-wise equality between v1 & v2
transform ( v1.begin( ), v1.end( ), v2.begin( ), v3.begin ( ),
not_equal_to<double>( ) );
cout << "The result of the element-wise not_equal_to comparsion\n"
<< "between v1 & v2 is: ( " ;
for ( Iter3 = v3.begin( ) ; Iter3 != v3.end( ) ; Iter3++ )
cout << *Iter3 << " ";
cout << ")" << endl;
}
The vector v1 = ( 0 1 4 5 8 9 )
The vector v2 = ( -0 1 -4 5 -8 9 )
The result of the element-wise not_equal_to comparsion
between v1 & v2 is: ( 0 0 1 0 1 0 )
Requirements
Header: <functional>
Namespace: std