A package for interval algebra calculations, with the implementation of Allen's interval algebra
Comparing function is a generic interface with operations to determine the relation between two Points of the same type t. They must implement all three properties described below:
interface CompareFunctions<t> {
smaller(a: t, b: t): boolean, // Returns true if a is strictly smaller than b
equal(a: t, b: t): boolean, // Returns true if a is equal b
greater(a: t, b: t): boolean, // Returns true if a is strictly greater than b
}The default implementation works with string, number and Date, the following implementation is an example for a different type than ones natively suported:
class MyClass {
constructor(public a: number, public b: string){}
}
const CustomCompareFunction: CompareFunctions<MyClass> = {
smaller: (a, b) => a.a < b.a, // Returns true if a is strictly smaller than b
equal: (a, b) => a.a == b.a, // Returns true if a is equal b
greater: (a, b) => a.a > b.a, // Returns true if a is strictly greater than b
}A point is a generic class that stores a data and can operate against other Points or Intervals given a Comparing Function.
Its constructor accepts two arguments:
| Argument | Type | Description |
|---|---|---|
| Value | Generic: t | The current value of the point |
| compareFunction | (optional) CompareFunctions<t> | The Comparing Function for that point |
example:
const p1 = new Point(2) // Point<number>
const p2 = new Point(new Date(), DateCompareFunction) // Point<Date>All methods of this class are related to comparisons betwees itself and other Point or Interval of same type.
Compares values of two points
| Function | Arguments | Return Type | Description |
|---|---|---|---|
| isSmaller | base: Point<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | the return of Point#compareFunction#smaler is true |
| isEqual | base: Point<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | the return of Point#compareFunction#equals is true |
| isGreater | base: Point<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | the return of Point#compareFunction#greater is true |
// With numbers
const p1 = new Point(2) // Point<number>
const p2 = new Point(3) // Point<number>
p1.isSmaller(p2) // true
p1.isEqual(new Point(2)) // true
p1.isGreater(p2) // false
// With Dates
const p1Date = new Point(new Date(100),) // Point<Date>
const p2Date = new Point(new Date(200)) // Point<Date>
p1Date.isSmaller(p2Date) // true
p2Date.isGreater(p1Date) // trueWith other types:
const p1 = new Point(new MyClass(1,"a")) // Point<number>
const p1WithComparation = new Point(new MyClass(1,"d"), CustomCompareFunction) // Point<number>
const p2 = new Point(new MyClass(2,"c")) // Point<number>
p1Date.isSmaller(p2Date) // false
p1WithComparation.isSmaller(p2Date) // true
p2Date.isGreater(p1Date) // false
p1Date.isSmaller(p2Date, CustomCompareFunction) // true
p2Date.isGreater(p1Date, CustomCompareFunction) // true
const AnotherCustomCompareFunction: CompareFunctions<MyClass> = {
smaller: (p1, p2) => p1.b < p2.b, // Returns true if a is strictly smaller than b
equal: (p1, p2) => p1.b == p2.b, // Returns true if a is equal b
greater: (p1, p2) => p1.b > p2.b, // Returns true if a is strictly greater than b
}
// If you pass a custom ComparationFunction it will be preferred
p1WithComparation.isSmaller(p2Date, AnotherCustomCompareFunction) // false, beacuse "d" > "c"Note: You should read Intervals first.
| Function | Arguments | Return Type | Description |
|---|---|---|---|
| isBefore | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Point is smaller than Base.start |
| isBaseStart | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Point is equal Base.start |
| isDuring | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Point is greater than Base.start AND Point is smaller than Base.end |
| isBaseEnd | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Point is equal Base.end |
| isAfter | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Point is greater than Base.end |
// With numbers
const p1 = new Point(1) // Point<number>
const p2 = new Point(2) // Point<number>
const p3 = new Point(3) // Point<number>
const p4 = new Point(4) // Point<number>
const p5 = new Point(5) // Point<number>
const interval = new Interval(2,4) // Interval<number>
p1.isBefore(interval) // true
p1.isBaseStart(interval) // false
p2.isBaseStart(interval) // true
p3.isDuring(interval) // true
p4.isBaseEnd(interval) // true
p5.isAfter(interval) // true// With other classes
const p1 = new Point(new MyClass(100, "a")) // Point<number>
const interval = new Interval(new MyClass(100, "b"), new MyClass(200, "c")) // Interval<number>
p1.isBefore(interval) // false
p1.isBaseStart(interval) // false
p1.isDuring(interval) // false
p1.isBaseEnd(interval) // false
p1.isAfter(interval) // false, to solve pass a compare function to either the point constructor or the function call:
// Solution 1: Pass to the function call
p1.isBaseStart(interval, CustomCompareFunction) // true
// Solution 2: Pass to the constructor
const p1 = new Point(new MyClass(100, "a"), CustomCompareFunction) // Point<number>
p1.isBaseStart(interval) // true, beacuse 100 == 100
// Here you can also override the point Compare Function:
p1.isBaseStart(interval, AnotherCustomCompareFunction) // false, because "a" < "b"
p1.isBefore(interval, AnotherCustomCompareFunction) // true, because "a" < "b"A Interval is generic class that stores two points in ascending direction Its constructor accepts three arguments:
| Argument | Type | Description |
|---|---|---|
| start | Generic: t | The value of the start point of the interval |
| end | Generic: t | The value of the end point of the interval |
| compareFunction | (optional) CompareFunctions<t> | The Comparing Function for that point |
note: if compareFunction.smaller(end, start) the interval will be reversed, you can check if a interval is reversed with the property Interval#reverse
Interval Properties:
| Property | Type | Description |
|---|---|---|
| start | Point<t> | The current value of the start point of the interval |
| end | Point<t> | The current value of the end point of the interval |
| compareFunction | CompareFunctions<t> | The Comparing Function for that point |
| reverse | boolean | true if start and end were swaped during creation (see previous note) |
Methods:
| Function | Arguments | Return Type | Description |
|---|---|---|---|
| Start Point | |||
| startsBefore | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#start is before Base ░░░░████░░░░ Base (argument) ░░██░░░░░░░░ Target (self) |
| startsTogether | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#start is BaseStart ░░░░████░░░░ Base (argument) ░░░░██░░░░░░ Target (self) |
| startsDuring | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#start is during Base ░░░░████░░░░ Base (argument) ░░░░░██░░░░░ Target (self) |
| startsJustAfter | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#start is BaseEnd ░░░░████░░░░ Base (argument) ░░░░░░░░██░░ Target (self) |
| startsAfter | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#start is after Base ░░░░████░░░░ Base (argument) ░░░░░░░░░██░ Target (self) |
| End Point | |||
| endsBefore | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#end is before Base ░░░░████░░░░ Base (argument) ░██░░░░░░░░░ Target (self) |
| endsJustBefor | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#end is BaseStart ░░░░████░░░░ Base (argument) ░░██░░░░░░░░ Target (self) |
| endsDuring | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#end is during Base ░░░░████░░░░ Base (argument) ░░████░░░░░░ Target (self) |
| endsTogether | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#end is BaseEnd ░░░░████░░░░ Base (argument) ░░██████░░░░ Target (self) |
| endsAfter | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Interval#end is after Base ░░░░████░░░░ Base (argument) ░░░░░░░░██░░ Target (self) |
| Interval | |||
| precedes | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts before and ends before base (argument) ░░░░████░░░░ Base (argument) ░██░░░░░░░░░ Target (self) |
| isPrecededBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts after and ends after base (argument) ░░░░████░░░░ Base (argument) ░░░░░░░░░██░ Target (self) |
| meets | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts before and ends on base (argument) start ░░░░████░░░░ Base (argument) ░███░░░░░░░░ Target (self) |
| isMetBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts just after base ░░░░████░░░░ Base (argument) ░░░░░░░░███░ Target (self) |
| overlaps | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts before and ends during base (argument) ░░░░████░░░░ Base (argument) ░░████░░░░░░ Target (self) |
| isOverlapedBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts during and ends after base (argument) ░░░░████░░░░ Base (argument) ░░░░░░████░░ Target (self) |
| starts | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts with and ends during base (argument) ░░░░████░░░░ Base (argument) ░░░░███░░░░░ Target (self) |
| isStartedBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target Interval (caller) starts with and ends after base (argument) ░░░░████░░░░ Base (argument) ░░░░██████░░ Target (self) |
| contains | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target Interval (caller) starts before and ends after base (argument) ░░░░████░░░░ Base (argument) ░░████████░░ Target (self) |
| isContainedBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts during and ends during base (argument) ░░░░████░░░░ Base (argument) ░░░░░██░░░░░ Target (self) |
| finishes | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts during and ends with base (argument) ░░░░████░░░░ Base (argument) ░░░░░░██░░░░ Target (self) |
| isFinishedBy | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts before and ends with base (argument) ░░░░████░░░░ Base (argument) ░░██████░░░░ Target (self) |
| equals | Base: Interval<t>, (optional) compareFunction: CompareFunctions<t> | Boolean | Target (caller) starts with and ends with base (argument) ░░░░████░░░░ Base (argument) ░░░░████░░░░ Target (self) |
const base = new Interval(10,20) // ░░██░░
const interval1 = new Interval(5,15) // ░██░░░
const interval2 = new Interval(10,20) // ░░██░░
const interval3 = new Interval(15,25) // ░░░██░
const interval4 = new Interval(20,30) // ░░░░██
const interval5 = new Interval(25,30) // ░░░░░█
interval1.startsBefore(base) // true
interval2.startsTogether(base) // true
interval3.startsDuring(base) // true
interval4.startsJustAfter(base) // true
interval5.startsAfter(base) // true const base = new Interval(10,20) // ░░██░░
const interval1 = new Interval(0,5) // █░░░░░
const interval2 = new Interval(0,10) // ██░░░░
const interval3 = new Interval(5,15) // ░██░░░
const interval4 = new Interval(10,20) // ░░██░░
const interval5 = new Interval(20,30) // ░░░░██
interval1.endsBefore(base) // true
interval2.endsJustBefor(base) // true
interval3.endsDuring(base) // true
interval4.endsTogether(base) // true
interval5.endsAfter(base) // true const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(1,3) // ░██░░░░░░░░░
target.precedes(base) // true
base.isPrecededBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(2,4) // ░░██░░░░░░░░
target.meets(base) // true
base.isMetBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(3,5) // ░░░██░░░░░░░
target.overlaps(base) // true
base.isOverlapedBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(4,6) // ░░░░██░░░░░░
target.starts(base) // true
base.isStartedBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(3,9) // ░░░██████░░░
target.contains(base) // true
base.isContainedBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(5,8) // ░░░░░███░░░░
target.finishes(base) // true
base.isFinishedBy(target) // true
const base = new Interval(4,8) // ░░░░████░░░░
const target = new Interval(4,8) // ░░░░████░░░░
target.equals(base) // true const base = new Interval(
new MyClass(10,"c"), // ░░░░░█████░░░░░
new MyClass(20,"g") // --c---g--
)
const interval = new Interval(
new MyClass(12,"b"), // ░░░░░░███░░░░░
new MyClass(18,"h"), // -b-----h-
CustomCompareFunction
)
interval.isContainedBy(base) // true
base.contains(interval) // false, lacks a proper comparation function
base.contains(interval, CustomCompareFunction) // true
interval.contains(base, AnotherCustomCompareFunction) // true
base.isContainedBy(interval, AnotherCustomCompareFunction) // true