Interval-Based Temporal Predicates

Files: timePredicates.go, timePredicates_test.go

A very simple implementation of some methods for an interval-based temporal logic based on James F. Allen's work.
This code can be used to implement scheduling/planning algorithms.

Location

A location l is a point in space with a heading:

l = {x, y, z, theta}

Location methods

Constructors:

func NewLocation(x float64, y float64, z float64, theta float64) Location

func (l *Location) MakeNewLocation(x float64, y float64, z float64, theta float64)

Event

An event ev is a timed location:

ev = {t, l}

Event Methods

Constructors:

func NewEvent(t time.Time, l Location) Event

func (ev *Event) MakeNewEvent(t time.Time, l Location)

Getters:

func (ev Event) GetEventTime() time.Time

func (ev Event) GetEventLocation() Location

Event Time Predicates:

// After: After reports whether the event ev1 is after ev2.
func (ev1 Event) After(ev2 Event) bool

// Before: Before reports whether the event ev1 is before ev2.
func (ev1 Event) Before(ev2 Event) bool

// Meets: Meets reports whether the event ev1 equals ev2.
func (ev1 Event) Meets(ev2 Event) bool

Event Interval

An event interval ei is a pair of events that identify a time interval in space-time between two events ev1, ev2:

ei = {ev1, ev2}

Event Interval Methods

Constructors:

func NewEventInterval(ev1 Event, ev2 Event) EventInterval

func (ei *EventInterval) MakeNewEventInterval(ev1 Event, ev2 Event)

Getters:

func (ei EventInterval) GetStartEvent() Event

func (ei EventInterval) GetEndEvent() Event

func (ei EventInterval) GetEventIntervalStartTime() time.Time

func (ei EventInterval) GetEventIntervalEndTime() time.Time

func (ei EventInterval) GetEventIntervalStartLocation() Location

func (ei EventInterval) GetEventIntervalEndLocation() Location

Event Interval Time Predicates:

// After: After reports whether the event interval e11 is after ei2.
// [ev1----ei2---ev2]...[ev1----ei1----ev2]
func (ei1 EventInterval) After(ei2 EventInterval) bool

// Before: Before reports whether the event interval e11 is before ei2.
// [ev1----ei1---ev2]...[ev1----ei2----ev2]
func (ei1 EventInterval) Before(ei2 EventInterval) bool

// Meets: Meets reports whether the event interval ei1 meets ei2: this happens
// when ei1.ev2 meets ei2.ev1
// [ev1----ei1---ev2][ev1----ei2----ev2]
func (ei1 EventInterval) Meets(ei2 EventInterval) bool

// Overlaps: Overlaps reports whether the event interval ei1 overlaps ei2:
// 1.
// [ev1----ei1----ev2]
//           [ev1----ei2----ev2]
// 2.
// [ev1----ei1----ev2]
//                   [ev1----ei2----ev2]
// 3.
// [ev1----ei1----ev2]
//     [ev1--ei2--ev2]
// 4.
// [ev1----ei1----ev2]
// [ev1----ei2----ev2]
func (ei1 EventInterval) Overlaps(ei2 EventInterval) bool

// Starts: Starts reports whether the event interval ei1 starts at the same time event of ei2:
// [ev1----ei1----ev2]
// [ev1--------ei2--------ev2]
func (ei1 EventInterval) Starts(ei2 EventInterval) bool

// Finishes: Finishes reports whether the event interval ei1 ends at the same time event of ei2:
//         [ev1----ei1----ev2]
// [ev1--------ei2--------ev2]
func (ei1 EventInterval) Finishes(ei2 EventInterval) bool

// During: During reports whether the event interval ei1 starts and ends, or is contained, within i2:
//     [ev1----ei1----ev2]
// [ev1--------ei2--------ev2]
func (ei1 EventInterval) During(ei2 EventInterval) bool

Examples

See the test file timePredicates_test.go