Class template quantity<BOOST_UNITS_DIMENSIONLESS

Class template quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y>

boost::units::quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y>

Synopsis

// In header: <boost/units/quantity.hpp>

template<typename System, typename Y> 
class quantity<BOOST_UNITS_DIMENSIONLESS_UNIT(System), Y> {
public:
  // types
  typedef quantity< unit< dimensionless_type, System >, Y > this_type;     
  typedef Y                                                 value_type;    
  typedef System                                            system_type;   
  typedef dimensionless_type                                dimension_type;
  typedef unit< dimension_type, system_type >               unit_type;     

  // construct/copy/destruct
  quantity& operator=(const this_type &);
  template<typename YY> 
    quantity& operator=(const quantity< unit< dimension_type, system_type >, YY > &);
  template<typename System2> 
    quantity& operator=(const quantity< BOOST_UNITS_DIMENSIONLESS_UNIT(System2), Y > &);

  // public member functions
   quantity();
   quantity(value_type);
   quantity(const this_type &);
  template<typename YY> 
     quantity(const quantity< unit< dimension_type, system_type >, YY > &, 
              unspecified = 0);
  template<typename YY> 
     quantity(const quantity< unit< dimension_type, system_type >, YY > &, 
              unspecified = 0);
  template<typename System2, typename Y2> 
     quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > &, 
              unspecified = 0, unspecified = 0, unspecified = 0);
  template<typename System2, typename Y2> 
     quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > &, 
              unspecified = 0, unspecified = 0, unspecified = 0);
  template<typename System2, typename Y2> 
     quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > &, 
              unspecified = 0);
  operator value_type() const;
  const value_type & value() const;
  this_type & operator+=(const this_type &);
  this_type & operator-=(const this_type &);
  this_type & operator*=(const value_type &);
  this_type & operator/=(const value_type &);

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

Description

Specialization for dimensionless quantities. Implicit conversions between unit systems are allowed because all dimensionless quantities are equivalent. Implicit construction and assignment from and conversion to value_type is also allowed.

`quantity` public construct/copy/destruct

quantity& operator=(const this_type & source);

template<typename YY> 
  quantity& operator=(const quantity< unit< dimension_type, system_type >, YY > & source);

implicit assignment between value types is allowed if allowed for value types themselves

template<typename System2> 
  quantity& operator=(const quantity< BOOST_UNITS_DIMENSIONLESS_UNIT(System2), Y > & source);

implicit assignment between different unit systems is allowed

`quantity` public member functions

```
 quantity();
```
```
 quantity(value_type val);
```
construction from raw value_type is allowed
```
 quantity(const this_type & source);
```

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

implicit conversion between value types is allowed if allowed for value types themselves

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

implicit conversion between value types is not allowed if not allowed for value types themselves

template<typename System2, typename Y2> 
   quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > & source, 
            unspecified = 0, unspecified = 0, unspecified = 0);

implicit conversion between different unit systems is allowed

template<typename System2, typename Y2> 
   quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > & source, 
            unspecified = 0, unspecified = 0, unspecified = 0);

implicit conversion between different unit systems is allowed

template<typename System2, typename Y2> 
   quantity(const quantity< unit< dimensionless_type, System2 >, Y2 > & source, 
            unspecified = 0);

conversion between different unit systems is explicit when the units are not equivalent.

```
operator value_type() const;
```
implicit conversion to value_type is allowed
```
const value_type & value() const;
```
constant accessor to value
can add a quantity of the same type if add_typeof_helper<value_type,value_type>::type is convertible to value_type
```
this_type & operator+=(const this_type & source);
```
can subtract a quantity of the same type if subtract_typeof_helper<value_type,value_type>::type is convertible to value_type
```
this_type & operator-=(const this_type & source);
```
can multiply a quantity by a scalar value_type if multiply_typeof_helper<value_type,value_type>::type is convertible to value_type
```
this_type & operator*=(const value_type & val);
```
can divide a quantity by a scalar value_type if divide_typeof_helper<value_type,value_type>::type is convertible to value_type

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

`quantity` public static functions

static this_type from_value(const value_type & val);

Construct quantity directly from value_type.