87 lines
2.8 KiB
C++
87 lines
2.8 KiB
C++
|
// Copyright 2018 Hans Dembinski
|
||
|
|
//
|
||
|
|
// Distributed under the Boost Software License, Version 1.0.
|
||
|
|
// (See accompanying file LICENSE_1_0.txt
|
||
|
|
// or copy at http://www.boost.org/LICENSE_1_0.txt)
|
||
|
|
|
||
|
|
#ifndef BOOST_HISTOGRAM_AXIS_POLYMORPHIC_BIN_HPP
|
||
|
|
#define BOOST_HISTOGRAM_AXIS_POLYMORPHIC_BIN_HPP
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
namespace histogram {
|
||
|
|
namespace axis {
|
||
|
|
|
||
|
|
/**
|
||
|
|
Holds the bin data of an axis::variant.
|
||
|
|
|
||
|
|
The interface is a superset of the axis::interval_view
|
||
|
|
class. In addition, the object is implicitly convertible to the value type,
|
||
|
|
returning the equivalent of a call to lower(). For discrete axes, lower() ==
|
||
|
|
upper(), and width() returns zero.
|
||
|
|
|
||
|
|
This is not a view like axis::interval_view for two reasons.
|
||
|
|
- Sequential calls to lower() and upper() would have to each loop through
|
||
|
|
the variant types. This is likely to be slower than filling all the data in
|
||
|
|
one loop.
|
||
|
|
- polymorphic_bin may be created from a temporary instance of axis::variant,
|
||
|
|
like in the call histogram::axis(0). Storing a reference to the axis would
|
||
|
|
result in a dangling reference. Rather than specialing the code to handle
|
||
|
|
this, it seems easier to just use a value instead of a view.
|
||
|
|
*/
|
||
|
|
template <class RealType>
|
||
|
|
class polymorphic_bin {
|
||
|
|
using value_type = RealType;
|
||
|
|
|
||
|
|
public:
|
||
|
|
polymorphic_bin(value_type lower, value_type upper)
|
||
|
|
: lower_or_value_(lower), upper_(upper) {}
|
||
|
|
|
||
|
|
/// Implicitly convert to bin value (for axis with discrete values).
|
||
|
|
operator const value_type&() const noexcept { return lower_or_value_; }
|
||
|
|
|
||
|
|
/// Return lower edge of bin.
|
||
|
|
value_type lower() const noexcept { return lower_or_value_; }
|
||
|
|
/// Return upper edge of bin.
|
||
|
|
value_type upper() const noexcept { return upper_; }
|
||
|
|
/// Return center of bin.
|
||
|
|
value_type center() const noexcept { return 0.5 * (lower() + upper()); }
|
||
|
|
/// Return width of bin.
|
||
|
|
value_type width() const noexcept { return upper() - lower(); }
|
||
|
|
|
||
|
|
template <class BinType>
|
||
|
|
bool operator==(const BinType& rhs) const noexcept {
|
||
|
|
return equal_impl(rhs, 0);
|
||
|
|
}
|
||
|
|
|
||
|
|
template <class BinType>
|
||
|
|
bool operator!=(const BinType& rhs) const noexcept {
|
||
|
|
return !operator==(rhs);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// Return true if bin is discrete.
|
||
|
|
bool is_discrete() const noexcept { return lower_or_value_ == upper_; }
|
||
|
|
|
||
|
|
private:
|
||
|
|
bool equal_impl(const polymorphic_bin& rhs, int) const noexcept {
|
||
|
|
return lower_or_value_ == rhs.lower_or_value_ && upper_ == rhs.upper_;
|
||
|
|
}
|
||
|
|
|
||
|
|
template <class BinType>
|
||
|
|
auto equal_impl(const BinType& rhs, decltype(rhs.lower(), 0)) const noexcept {
|
||
|
|
return lower() == rhs.lower() && upper() == rhs.upper();
|
||
|
|
}
|
||
|
|
|
||
|
|
template <class BinType>
|
||
|
|
bool equal_impl(const BinType& rhs, float) const noexcept {
|
||
|
|
return is_discrete() && static_cast<value_type>(*this) == rhs;
|
||
|
|
}
|
||
|
|
|
||
|
|
const value_type lower_or_value_, upper_;
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace axis
|
||
|
|
} // namespace histogram
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#endif
|