function
Let an agent handle functions by domain, codomain, rule and properties, and distinguish mathematical functions from programming functions and biological functions.
Bundle → Layer → Finding → Questions Filled
4 bundles · 8 layers · 8 findings · 16 questions
Definition Domain and rule.
Domain and codomain
Sets.
Domain
Domain and codomain.
- What are the domain and codomain? definition
- Is it defined for all inputs? boundary
Rule
How outputs are computed.
Rule
Defining rule.
- What rule defines it? definition
- Is it given by formula, table or algorithm? definition
Properties Behaviour.
Mapping properties
Injective, surjective.
Mapping
Mapping properties.
- Is it injective, surjective or bijective? measurement
- Does it have an inverse? boundary
Analytic properties
Continuity, differentiability.
Analysis
Analytic properties.
- Is it continuous and differentiable? measurement
- Where not? boundary
Representation Graphs and code.
Graph
Plot.
Graph
Graph.
- What does its graph look like? definition
- What are its key features? measurement
Computation
Evaluation.
Computation
Numerical evaluation.
- How can it be evaluated accurately? action
- Where is it numerically unstable? boundary
Use Modelling.
Model
Applications.
Model
Modelling use.
- What relationship does it model? definition
- How well does it fit data? measurement
Other senses
Programming and biology.
Senses
Disambiguation.
- Is the mathematical sense meant? boundary
- Which other entry fits better? action
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.QLT
What it is Filled
In mathematics, a relation that assigns to each element of a set (the domain) exactly one element of another set (the codomain).
Why it exists Filled
Let an agent handle functions by domain, codomain, rule and properties, and distinguish mathematical functions from programming functions and biological functions.
Distinguishing features Filled
- Each input has exactly one output
- Defined with domain and codomain
- Partial functions leave some inputs undefined
- Properties include injective, surjective, bijective
What robots and AI may and may not do Filled
Must not
- Misstate a function's domain or properties in a proof or calculation.
- Present an unverified proof as correct.
- Claim credit for others' mathematical work.
Only with a human decision
- Using mathematical results in safety-critical systems.
May
- Define, compute and analyse functions.
- Explain function concepts to learners.
Moral aspects Filled
- Mathematical errors can propagate into critical systems.
- Credit for results matters to mathematicians.
Who is affected
- Students
- Users of mathematical results
Owners Filled
Steward
Nobody owns a mathematical concept; it is held in common.
Links to other meta-models Filled
parent
- Q130901 - registry parent class
- Q1756942 - registry parent class
related
- binary relation - mathematics
- mathematics - analysis
- function in programming or biology - other senses
- curve - graph
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.function
- Wikidata: Q11348 (https://www.wikidata.org/wiki/Q11348)
- DLMF chapter: NIST DLMF identifiers special functions
Direct properties not applicable Not applicable
Not applicable
Plane XCT: no invented physical properties.
Recognition optional Filled
- Notation f: A -> B
- Graphs passing the vertical line test
- Programming functions are a related but different sense
- Formulas such as f(x) = x squared, graphs and tables.
Capabilities and actions required Filled
- define it by a rule, table or graph
- evaluate it at points
- study its properties such as continuity
- compose and invert it where possible
Hazards and failure modes required Filled
- Evaluating outside the domain
- Confusing a function with its formula
- Assuming invertibility
Standards and interfaces required Filled
- ISO 80000-2 notation
Context of use required Filled
- Describing dependence between quantities in mathematics, science and computing.
- polynomial, rational, exponential and trigonometric functions
- injective, surjective and bijective functions
- partial functions
- multivariable functions
Sources Filled
- Wikidata item Q11348: function - identity and sense of the item
- Wikipedia: Function (mathematics) - general description of the item
Open questions
- Should classes of functions be separate entries?
- How should programming functions be linked?
- How should special functions be catalogued?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q11348/spec.json