supernovas::ScalarEvolution Class Reference

The evolution of a scalar quantity in time, based on a local quadratic approximation. More...

#include <supernovas.h>

Inheritance diagram for supernovas::ScalarEvolution:

Public Member Functions
	ScalarEvolution (double value, double rate=0.0, double accel=0.0)
	Instantiate an time evolution set for a scalar quantity.
double	acceleration () const
	Returns the defined (constant) acceleration value.
double	rate (const Interval &offset=Interval::zero()) const
	Returns an extrapolated momentary rate of change for the evolving quantity at an offset time, using the defined acceleration.
double	value (const Interval &offset=Interval::zero()) const
	Returns an extrapolated momentary value of the evolving quantity at an offset time, using the defined derivatives.
Public Member Functions inherited from supernovas::Validating
bool	is_valid () const
	Returns the previously set 'valid' stae of the implementing instance.
	operator bool () const
	Objects that implement Validating can be used in conditionals directly, without explicitly calling is_valid().

Static Public Member Functions
static ScalarEvolution	stationary (double value)
	Returns a new scalar evolution instance for a stationary quantity.
static const ScalarEvolution &	undefined ()
	Returns a reference to a statically allocated undefined scalar evolution instance.

Additional Inherited Members
Protected Member Functions inherited from supernovas::Validating
	Validating ()
	dummy constructor;
Protected Attributes inherited from supernovas::Validating
bool	_valid = false
	the state variable.

Detailed Description

The evolution of a scalar quantity in time, based on a local quadratic approximation.

See also

Track

Constructor & Destructor Documentation

ScalarEvolution()

supernovas::ScalarEvolution::ScalarEvolution ( double value, double rate = 0.0, double accel = 0.0 )

explicit

Instantiate an time evolution set for a scalar quantity.

Parameters

value	[?] momentary value
rate	[?/s] (optional) momentary rate of change in value (default: 0).
accel	[?/s2] (optional) momentary acceleration of value (default: 0).

References supernovas::Validating::_valid, rate(), and value().

Member Function Documentation

acceleration()

double supernovas::ScalarEvolution::acceleration

(

)

const

Returns the defined (constant) acceleration value.

Returns

the acceleration that was defined.

See also

value(), rate()

rate()

double supernovas::ScalarEvolution::rate

(

const Interval &

offset = Interval::zero()

)

const

Returns an extrapolated momentary rate of change for the evolving quantity at an offset time, using the defined acceleration.

Parameters

offset

time offset from when reference value and derivatives were defined.

Returns

the extrapolated momentary rate of change at the offset time.

See also

value(), acceleration()

References supernovas::Interval::seconds().

Referenced by ScalarEvolution().

stationary()

ScalarEvolution supernovas::ScalarEvolution::stationary ( double value )

static

Returns a new scalar evolution instance for a stationary quantity.

Parameters

value

The stationary (unevolving) value

Returns

a non-evolving scalar evolution instance with the specified stationary value.

References supernovas::Validating::is_valid(), and value().

undefined()

const ScalarEvolution & supernovas::ScalarEvolution::undefined ( )

static

Returns a reference to a statically allocated undefined scalar evolution instance.

Returns

a reference to a static undefined scalar evolution instance.

value()

double supernovas::ScalarEvolution::value

(

const Interval &

offset = Interval::zero()

)

const

Returns an extrapolated momentary value of the evolving quantity at an offset time, using the defined derivatives.

Parameters

offset

time offset from when reference value and derivatives were defined.

Returns

the extrapolated momentary scalar value at the offset time.

See also

rate(), acceleration()

References supernovas::Interval::seconds().

Referenced by ScalarEvolution(), and stationary().