| Copyright | (c) NoviSci Inc 2020 |
|---|---|
| License | BSD3 |
| Maintainer | bsaul@novisci.com |
| Stability | experimental |
| Safe Haskell | None |
| Language | Haskell2010 |
IntervalAlgebra
Description
The IntervalAlgebra module provides data types and related classes for the
interval-based temporal logic described in Allen (1983)
and axiomatized in Allen and Hayes (1987).
A good primer on Allen's algebra can be found here.
Design
The module is built around four typeclasses designed to separate concerns of
constructing, relating, and combining s: Interval
provides an interface to the data structure of anIntervallic, defining how anIntervalis constructed.Intervalaprovides an interface to theIntervalAlgebraic, the workhorse of Allen's temporal logic.IntervalRelationsprovides an interface to methods of combining twoIntervalCombinable.Intervalsand the relatedIntervalSizeableprovides methods for measuring and modifying the size of an interval. collections of intervals.Moment
An advantage of nested typeclass design is that developers can define an
of type Intervala with just the amount of structure that they need.
Total Ordering of Intervals
The modules makes the (opinionated) choice of a total ordering for Intervallics. Namely, the ordering is based on first ordering the Intervalbegins
then the ends.
Development
This module is under development and the API may change in the future.
Synopsis
- class (Ord a, Show a) => Intervallic a where
- parseInterval :: a -> a -> Either String (Interval a)
- unsafeInterval :: a -> a -> Interval a
- begin, end :: Interval a -> a
- class (Eq a, Intervallic a) => IntervalAlgebraic a where
- relate :: Interval a -> Interval a -> IntervalRelation a
- predicate' :: IntervalRelation a -> ComparativePredicateOf (Interval a)
- predicates :: Set (IntervalRelation a) -> [ComparativePredicateOf (Interval a)]
- predicate :: Set (IntervalRelation a) -> ComparativePredicateOf (Interval a)
- toSet :: [IntervalRelation a] -> Set (IntervalRelation a)
- compose :: IntervalRelation a -> IntervalRelation a -> Set (IntervalRelation a)
- complement :: Set (IntervalRelation a) -> Set (IntervalRelation a)
- intersection :: Set (IntervalRelation a) -> Set (IntervalRelation a) -> Set (IntervalRelation a)
- union :: Set (IntervalRelation a) -> Set (IntervalRelation a) -> Set (IntervalRelation a)
- converse :: Set (IntervalRelation a) -> Set (IntervalRelation a)
- equals :: ComparativePredicateOf (Interval a)
- meets, metBy :: ComparativePredicateOf (Interval a)
- before, after :: ComparativePredicateOf (Interval a)
- overlaps, overlappedBy :: ComparativePredicateOf (Interval a)
- starts, startedBy :: ComparativePredicateOf (Interval a)
- precedes, precededBy :: ComparativePredicateOf (Interval a)
- finishes, finishedBy :: ComparativePredicateOf (Interval a)
- during, contains :: ComparativePredicateOf (Interval a)
- unionPredicates :: [ComparativePredicateOf (Interval a)] -> ComparativePredicateOf (Interval a)
- (<|>) :: ComparativePredicateOf (Interval a) -> ComparativePredicateOf (Interval a) -> ComparativePredicateOf (Interval a)
- disjointRelations :: Set (IntervalRelation a)
- withinRelations :: Set (IntervalRelation a)
- disjoint :: ComparativePredicateOf (Interval a)
- notDisjoint :: ComparativePredicateOf (Interval a)
- concur :: ComparativePredicateOf (Interval a)
- within :: ComparativePredicateOf (Interval a)
- enclose :: ComparativePredicateOf (Interval a)
- enclosedBy :: ComparativePredicateOf (Interval a)
- class IntervalAlgebraic a => IntervalCombinable a where
- (.+.) :: Interval a -> Interval a -> Maybe (Interval a)
- extenterval :: Interval a -> Interval a -> Interval a
- (><) :: Interval a -> Interval a -> Maybe (Interval a)
- (<+>) :: (Semigroup (f (Interval a)), Applicative f) => Interval a -> Interval a -> f (Interval a)
- intersect :: Interval a -> Interval a -> Maybe (Interval a)
- class (Intervallic a, Num b, Ord b) => Moment a b | a -> b where
- moment :: b
- class (Intervallic a, Moment a b, Num b, Ord b) => IntervalSizeable a b | a -> b where
- data Interval a
- data IntervalRelation a
- type ComparativePredicateOf a = a -> a -> Bool
Classes
class (Ord a, Show a) => Intervallic a where Source #
The typeclass specifies how an Intervallics is constructed.
It also includes functions for getting the Interval a and begin of an end.Interval a
Minimal complete definition
Nothing
Methods
parseInterval :: a -> a -> Either String (Interval a) Source #
Safely parse a pair of as to create an .Interval a
unsafeInterval :: a -> a -> Interval a Source #
Create a new . This function is not safe as it does
not enforce that \(x < y\). Use with caution. It is meant to be helper
function in early prototyping of this package. This function may be
deprecated in future releases.Interval a
begin :: Interval a -> a Source #
Access the ends of an .Interval a
end :: Interval a -> a Source #
Access the ends of an .Interval a
Instances
class (Eq a, Intervallic a) => IntervalAlgebraic a where Source #
The typeclass specifies the functions and relational
operators for interval-based temporal logic. The typeclass defines the
relational operators for intervals, plus other useful utilities such as
IntervalAlgebraic, disjoint, and within.unionPredicates
Minimal complete definition
Nothing
Methods
relate :: Interval a -> Interval a -> IntervalRelation a Source #
Compare two intervals to determine their IntervalRelation.
predicate' :: IntervalRelation a -> ComparativePredicateOf (Interval a) Source #
Maps an IntervalRelation to its corresponding predicate function.
predicates :: Set (IntervalRelation a) -> [ComparativePredicateOf (Interval a)] Source #
Given a set of IntervalRelations return a list of predicate functions
corresponding to each relation.
predicate :: Set (IntervalRelation a) -> ComparativePredicateOf (Interval a) Source #
Forms a predicate function from the union of a set of IntervalRelations.
toSet :: [IntervalRelation a] -> Set (IntervalRelation a) Source #
Shortcut to creating a 'Set IntervalRelation' from a list.
compose :: IntervalRelation a -> IntervalRelation a -> Set (IntervalRelation a) Source #
Compose two interval relations according to the rules of the algebra. The rules are enumerated according to this table.
complement :: Set (IntervalRelation a) -> Set (IntervalRelation a) Source #
Finds the complement of a 'Set IntervalRelation'.
intersection :: Set (IntervalRelation a) -> Set (IntervalRelation a) -> Set (IntervalRelation a) Source #
Find the intersection of two Sets of IntervalRelation
union :: Set (IntervalRelation a) -> Set (IntervalRelation a) -> Set (IntervalRelation a) Source #
Find the union of two Sets of IntervalRelation
converse :: Set (IntervalRelation a) -> Set (IntervalRelation a) Source #
Find the converse of a 'Set IntervalRelation'.
equals :: ComparativePredicateOf (Interval a) Source #
Does x equal y?
meets :: ComparativePredicateOf (Interval a) Source #
Does x meet y? Is y metBy x?
metBy :: ComparativePredicateOf (Interval a) Source #
Does x meet y? Is y metBy x?
before :: ComparativePredicateOf (Interval a) Source #
Is x before y? Is x after y?
after :: ComparativePredicateOf (Interval a) Source #
Is x before y? Is x after y?
overlaps :: ComparativePredicateOf (Interval a) Source #
Does x overlap y? Is x overlapped by y?
overlappedBy :: ComparativePredicateOf (Interval a) Source #
Does x overlap y? Is x overlapped by y?
starts :: ComparativePredicateOf (Interval a) Source #
Does x start y? Is x started by y?
startedBy :: ComparativePredicateOf (Interval a) Source #
Does x start y? Is x started by y?
precedes :: ComparativePredicateOf (Interval a) Source #
precededBy :: ComparativePredicateOf (Interval a) Source #
finishes :: ComparativePredicateOf (Interval a) Source #
Does x finish y? Is x finished by y?
finishedBy :: ComparativePredicateOf (Interval a) Source #
Does x finish y? Is x finished by y?
during :: ComparativePredicateOf (Interval a) Source #
Is x during y? Does x contain y?
contains :: ComparativePredicateOf (Interval a) Source #
Is x during y? Does x contain y?
unionPredicates :: [ComparativePredicateOf (Interval a)] -> ComparativePredicateOf (Interval a) Source #
Compose a list of interval relations with _or_ to create a new
. For example,
ComparativePredicateOf Interval aunionPredicates [before, meets] creates a predicate function determining
if one interval is either before or meets another interval.
(<|>) :: ComparativePredicateOf (Interval a) -> ComparativePredicateOf (Interval a) -> ComparativePredicateOf (Interval a) Source #
Operator for composing the union of two predicates
disjointRelations :: Set (IntervalRelation a) Source #
withinRelations :: Set (IntervalRelation a) Source #
disjoint :: ComparativePredicateOf (Interval a) Source #
notDisjoint :: ComparativePredicateOf (Interval a) Source #
Are x and y not disjoint; i.e. do they share any support?
concur :: ComparativePredicateOf (Interval a) Source #
A synonym for notDisjoint.
within :: ComparativePredicateOf (Interval a) Source #
enclose :: ComparativePredicateOf (Interval a) Source #
Does x enclose y? That is, is y within x?
enclosedBy :: ComparativePredicateOf (Interval a) Source #
Synonym for within.
Instances
class IntervalAlgebraic a => IntervalCombinable a where Source #
The typeclass provides methods for (possibly) combining
two IntervalCombinable.Intervals
Minimal complete definition
Nothing
Methods
(.+.) :: Interval a -> Interval a -> Maybe (Interval a) Source #
extenterval :: Interval a -> Interval a -> Interval a Source #
Creates a new Interval spanning the extent x and y
(><) :: Interval a -> Interval a -> Maybe (Interval a) Source #
If x is before y, then form a new Just Interval a from the
interval in the "gap" between x and y from the end of x to the
begin of y. Otherwise, Nothing.
(<+>) :: (Semigroup (f (Interval a)), Applicative f) => Interval a -> Interval a -> f (Interval a) Source #
If x is before y, return f x appended to f y. Otherwise,
return extenterval of x and y (wrapped in f). This is useful for
(left) folding over an *ordered* container of Intervals and combining
intervals when x is *not* before y.
intersect :: Interval a -> Interval a -> Maybe (Interval a) Source #
Forms a Just new interval from the intersection of two intervals,
provided the intervals are not disjoint.
Instances
class (Intervallic a, Num b, Ord b) => Moment a b | a -> b where Source #
The Moment class fixes the smallest duration of an 'Intervallic a'.
Minimal complete definition
Nothing
class (Intervallic a, Moment a b, Num b, Ord b) => IntervalSizeable a b | a -> b where Source #
The IntervalSizeable typeclass provides functions to determine the size of
and to resize an 'Interval a'.
Methods
duration :: Interval a -> b Source #
Determine the duration of an 'Interval a'.
Shifts an a. Most often, the b will be the same type as a.
But for example, if a is Day then b could be Int.
Takes the difference between two a to return a b.
expand :: b -> b -> Interval a -> Interval a Source #
Resize an 'Interval a' to by expanding to "left" by l and to the
"right" by r. In the case that l or r are less than a moment
the respective endpoints are unchanged.
expandl :: b -> Interval a -> Interval a Source #
Expands an 'Interval a' to left by i.
expandr :: b -> Interval a -> Interval a Source #
Expands an 'Interval a' to right by i.
beginerval :: b -> a -> Interval a Source #
Instances
Types
An is a pair of Interval aas \( (x, y) \text{ where } x < y\). The
class provides a safe Intervallic function that returns a
parseInterval error if \(y < x\) and LeftunsafeInterval as constructor for creating an
interval that may not be valid.
Instances
| Eq a => Eq (Interval a) Source # | |
| Intervallic a => Ord (Interval a) Source # | Imposes a total ordering on |
| (Intervallic a, Show a) => Show (Interval a) Source # | |
| Arbitrary (Interval Int) Source # | |
| Arbitrary (Interval Day) Source # | |
data IntervalRelation a Source #
The IntervalRelation type enumerates the thirteen possible ways that two
objects can relate according to the interval algebra.Interval a
Meets, Metby
x `meets` y y `metBy` x
x: |-----| y: |-----|
Before, After
x `before` y y `after` x
x: |-----| y: |-----|
Overlaps, OverlappedBy
x `overlaps` y y `overlappedBy` x
x: |-----| y: |-----|
Starts, StartedBy
x `starts` y y `startedBy` x
x: |---| y: |-----|
Finishes, FinishedBy
x `finishes` y y `finishedBy` x
x: |---| y: |-----|
During, Contains
x `during` y y `contains` x
x: |-| y: |-----|
Equal
x `equal` y y `equal` x
x: |-----| y: |-----|
Constructors
| Meets | |
| MetBy | |
| Before | |
| After | |
| Overlaps | |
| OverlappedBy | |
| Starts | |
| StartedBy | |
| Finishes | |
| FinishedBy | |
| During | |
| Contains | |
| Equals |
Instances
type ComparativePredicateOf a = a -> a -> Bool Source #
Defines a predicate of two objects of type a.