src/base/temperature.hh

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 * property including but not limited to intellectual property relating
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#ifndef __BASE_TEMPERATURE_HH__
#define __BASE_TEMPERATURE_HH__

#include <ostream>

namespace gem5
{

/**
 * The class stores temperatures in Kelvin and provides helper methods
 * to convert to/from Celsius.
 */
class Temperature
{

  private:
    /** Temperature in Kelvin */
    double value;

  public:
    /** Explicit constructor assigning a value. */
    explicit constexpr Temperature(double _value=0.0)
        : value(_value)
    {
    }

    static Temperature fromKelvin(double _value);
    static Temperature fromCelsius(double _value);
    static Temperature fromFahrenheit(double _value);

    constexpr double toKelvin() const { return value; }
    constexpr double toCelsius() const { return value - 273.15; }
    double toFahrenheit() const;

    constexpr bool
    operator>(const Temperature &rhs) const
    {
        return value > rhs.value;
    }

    constexpr bool
    operator>=(const Temperature &rhs) const
    {
        return value >= rhs.value;
    }

    constexpr bool
    operator<(const Temperature &rhs) const
    {
        return value < rhs.value;
    }

    constexpr bool
    operator<=(const Temperature &rhs) const
    {
        return value <= rhs.value;
    }

    constexpr bool
    operator==(const Temperature &rhs) const
    {
        return value == rhs.value;
    }

    constexpr bool
    operator!=(const Temperature &rhs) const
    {
        return value != rhs.value;
    }

    constexpr Temperature
    operator+(const Temperature &rhs) const
    {
        return Temperature(value + rhs.value);
    }

    constexpr Temperature
    operator-(const Temperature &rhs) const
    {
        return Temperature(value - rhs.value);
    }

    friend constexpr Temperature operator*(
        const Temperature &lhs, const double &rhs);

    friend constexpr Temperature operator*(
        const double &lhs, const Temperature &rhs);

    friend constexpr Temperature operator/(
        const Temperature &lhs, const double &rhs);

    Temperature &
    operator+=(const Temperature &rhs)
    {
        value += rhs.value;
        return *this;
    }

    Temperature &
    operator-=(const Temperature &rhs)
    {
        value -= rhs.value;
        return *this;
    }

    Temperature &
    operator*=(const double &rhs)
    {
        value *= rhs;
        return *this;
    }

    Temperature &
    operator/=(const double &rhs)
    {
        value /= rhs;
        return *this;
    }

    friend std::ostream &operator<<(std::ostream &out, const Temperature &t);
};

constexpr Temperature
operator*(const Temperature &lhs, const double &rhs)
{
    return Temperature(lhs.value * rhs);
}

constexpr Temperature
operator*(const double &lhs, const Temperature &rhs)
{
    return Temperature(lhs * rhs.value);
}

constexpr Temperature
operator/(const Temperature &lhs, const double &rhs)
{
    return Temperature(lhs.value / rhs);
}

} // namespace gem5

#endif // __BASE_TEMPERATURE_HH__