Boost C++ Libraries

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Class template quantity

boost::units::quantity — class declaration

Synopsis

template<typename Unit, typename Y = double> 
class quantity {
public:
  // types
  typedef quantity< Unit, Y > this_type; 
  typedef Y                   value_type;
  typedef Unit                unit_type; 

  // construct/copy/destruct
  quantity();
  quantity(const this_type &);
  template<typename YY> 
    quantity(const quantity< Unit, YY > &, unspecified = 0);
  template<typename YY> 
    quantity(const quantity< Unit, YY > &, unspecified = 0);
  template<typename Unit2, typename YY> 
    quantity(const quantity< Unit2, YY > &, unspecified = 0);
  template<typename Unit2, typename YY> 
    quantity(const quantity< Unit2, YY > &, unspecified = 0);
  quantity(const value_type &);
  quantity& operator=(const this_type &);
  template<typename YY> quantity& operator=(const quantity< Unit, YY > &);
  template<typename Unit2, typename YY> 
    quantity& operator=(const quantity< Unit2, YY > &);

  // private member functions
   BOOST_MPL_ASSERT_NOT(unspecified) ;

  // public member functions
  const value_type & value() const;
  template<typename Unit2, typename YY> 
    this_type & operator+=(const quantity< Unit2, YY > &) ;
  template<typename Unit2, typename YY> 
    this_type & operator-=(const quantity< Unit2, YY > &) ;
  template<typename Unit2, typename YY> 
    this_type & operator*=(const quantity< Unit2, YY > &) ;
  template<typename Unit2, typename YY> 
    this_type & operator/=(const quantity< Unit2, YY > &) ;
  this_type & operator*=(const value_type &) ;
  this_type & operator/=(const value_type &) ;

  // public static functions
  static this_type from_value(const value_type &) ;
};

Description

`quantity` public construct/copy/destruct

```
quantity();
```
```
quantity(const this_type & source);
```

template<typename YY> 
  quantity(const quantity< Unit, YY > & source, unspecified = 0);

template<typename YY> 
  quantity(const quantity< Unit, YY > & source, unspecified = 0);

template<typename Unit2, typename YY> 
  quantity(const quantity< Unit2, YY > & source, unspecified = 0);

template<typename Unit2, typename YY> 
  quantity(const quantity< Unit2, YY > & source, unspecified = 0);

```
quantity(const value_type & val);
```

quantity& operator=(const this_type & source);

template<typename YY> quantity& operator=(const quantity< Unit, YY > & source);

template<typename Unit2, typename YY> 
  quantity& operator=(const quantity< Unit2, YY > & source);

`quantity` private member functions

```
 BOOST_MPL_ASSERT_NOT(unspecified) ;
```

`quantity` public member functions

```
const value_type & value() const;
```
can add a quantity of the same type if add_typeof_helper<value_type,value_type>::type is convertible to value_type

template<typename Unit2, typename YY> 
  this_type & operator+=(const quantity< Unit2, YY > & source) ;

template<typename Unit2, typename YY> 
  this_type & operator-=(const quantity< Unit2, YY > & source) ;

template<typename Unit2, typename YY> 
  this_type & operator*=(const quantity< Unit2, YY > & source) ;

template<typename Unit2, typename YY> 
  this_type & operator/=(const quantity< Unit2, YY > & source) ;

this_type & operator*=(const value_type & source) ;

this_type & operator/=(const value_type & source) ;

`quantity` public static functions

static this_type from_value(const value_type & val) ;

value_type

Specializations

Class template quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y>