coordinate axis
Enable an AI agent to recognise a coordinate axis, interpret positions relative to it, and determine which readings or transformations its coordinate conventions support.
Bundle → Layer → Finding → Questions Filled
6 bundles · 11 layers · 16 findings · 26 questions
Coordinate role Establishes what makes this reference a coordinate axis and which coordinate it organises.
Axis interpretation
Identifies the geometric or representational sense in use.
Coordinate assignment role
Record the convention that gives the axis its coordinate role without presuming every axis is a spatial straight line.
- Does this axis denote a geometric reference, a chart value guide, or another explicitly defined coordinate construct? definition
- What distinguishes it here from a symmetry axis, rotation axis, or decorative guide? boundary
System membership
Connects the axis to its parent system and component identity.
Component binding
Record the parent system, component name or index, and the convention establishing their association.
- Which coordinate system and coordinate component does this axis belong to? definition
- Which specification, construction, or annotation establishes that association? provenance
Reference and direction Captures where the axis is anchored and how increasing coordinates are oriented.
Reference placement
Separates coordinate reference positions from graphical placement.
Zero and baseline
Record the coordinate reference and whether it coincides with the displayed axis intersection or baseline.
- What establishes the coordinate reference, and is zero included in the axis's domain? definition
- Does the drawn intersection represent the coordinate origin, or is the axis displayed at an offset? boundary
Axis orientation
Makes positive direction explicit relative to a frame or display.
Increasing coordinate direction
Record how increasing values relate to geometric or displayed direction.
- In which direction do coordinate values increase, relative to which frame? definition
- How must existing coordinate values change if this direction is reversed? action
Values and scale Defines admissible coordinate values and their mapping to positions.
Coordinate domain
Records units and restrictions on coordinate values.
Admissible values
Record the value domain, units, endpoint rules, and any periodic identification.
- What units or dimensionless convention apply to this coordinate? measurement
- Which values are permitted, and are any endpoints excluded or identified through periodicity? boundary
Position mapping
Captures how coordinate values become geometric or displayed positions.
Scale and inverse
Record the mapping, its parameters, and the conditions under which a position yields a unique value.
- What mapping connects coordinate values to positions, including any logarithmic base, breaks, or piecewise rules? definition
- Over which positions can an agent recover a unique coordinate value? boundary
Geometry and component reading Relates the axis to companion axes and determines how coordinates are obtained.
Companion axis relations
Records the geometric relationships relevant to interpreting this axis.
Basis and metric context
Identify any associated basis direction, metric, and companion-axis relationships without assuming orthogonality or unit length.
- Is this axis associated with a basis vector, and what fixes that vector's scale? definition
- Under the specified metric, what angles or orthogonality relationships hold with companion axes? measurement
Coordinate extraction
Determines the operation that obtains this component from a point or representation.
Valid reading operation
Record whether component extraction uses perpendicular projection, basis decomposition, a coordinate function, or a display mapping.
- Which operation obtains this axis's coordinate from a given point? action
- When, if ever, does that coordinate equal a signed geometric distance? boundary
Re-expression and readiness Controls changes to axis conventions and assesses whether a requested operation is supported.
Axis transformations
Distinguishes changes in display from changes in coordinate conventions.
Transformation contract
Specify how values and axis metadata change under unit conversion, origin shifts, direction reversal, or frame changes.
- Does the proposed change alter display placement, coordinate values, the reference frame, or several of these? boundary
- What mapping and companion-coordinate information are required to preserve the represented points? action
Interpretation checks
Identifies missing or inconsistent conventions before an axis is used.
Operation-specific readiness
Assess whether available labels, units, directions, and mappings support the intended reading or comparison.
- Are the axis label, unit, ticks, and declared mapping mutually consistent where they are present? measurement
- Which missing conventions must be resolved before the requested reading, comparison, or transformation can proceed? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these kinds and varieties hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these typical measurements hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of coordinate axis this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.QTY
- Other names and narrower kinds
- cartesian coordinate axis, vehicle axis, body axis, axes conventions, dorsal/ventral axis, medial/lateral axis
What it is Filled
A coordinate axis is a reference line in a coordinate system, typically passing through its origin and assigned a direction and scale, along which one coordinate is represented.
In scope
- The axis's identity and role within its parent coordinate system
- Its reference position, direction, and geometric realisation
- The values, units, domain, and scale assigned along it
- Its relationships to other axes and to coordinate components
- Conditions for interpreting, comparing, or transforming axis readings
Out of scope
- The complete coordinate system, manifold, or reference frame
- The measured object or physical quantity represented by a coordinate
- A complete chart, including data series, legends, and analytical claims
- Symmetry axes, rotation axes, and mechanical shafts without a coordinate role
- Coordinate transformations considered independently of the axis they affect
Why it exists Filled
Enable an AI agent to recognise a coordinate axis, interpret positions relative to it, and determine which readings or transformations its coordinate conventions support.
Distinguishing features Filled
- A line or direction qualifies through an explicit coordinate-assignment role; straightness alone does not make it a coordinate axis.
- An axis belongs to a coordinate convention that identifies which component or variable it represents.
- A geometric coordinate axis can exist without being drawn, while an axis drawn on a chart may serve as a value guide without representing a spatial line.
- An axis is distinct from a basis vector: the vector supplies direction and magnitude information, while the axis additionally has a coordinate-system role and reference conventions.
- A rotation or symmetry axis is also a coordinate axis only when a coordinate system explicitly uses it that way.
What robots and AI may and may not do Filled
Must not
- Truncate or rescale an axis in a way that misleads readers about the size of a change.
- Swap or mislabel axes, such as latitude and longitude, without flagging it.
- Combine data from systems with different axis directions or origins without converting.
- Drive a machine or robot along an axis whose zero point and direction have not been confirmed.
Only with a human decision
- Changing axis conventions in a shared engineering or mapping system that others depend on.
May
- Label the axes of a chart or coordinate system with the quantity, unit and direction.
- Convert values between coordinate systems, stating the axis conventions used.
- Check that axis orientation and handedness match between data sources before combining them.
Moral aspects Filled
- Axis choices in charts shape how people judge evidence, including in public health and elections.
- Axis mix-ups in engineering and navigation have caused costly and dangerous errors.
Who is affected
- Readers of charts
- Engineers and operators
- People relying on maps and positions
Owners Filled
Steward
Nobody owns the concept; the author of each chart or system answers for its axes.
Links to other meta-models Filled
parent
- Q138638473 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.coordinate-axis
- Wikidata: Q1783819 (https://www.wikidata.org/wiki/Q1783819)
Direct properties not applicable Not applicable
- Axis interpretation: geometric coordinate axis; chart coordinate axis; other explicitly defined convention
- Parent coordinate system: Identified coordinate system or display coordinate mapping
- Coordinate component: Named or indexed component, such as x, y, z, or a declared variable
- Reference position: Origin, zero location, display baseline, or another declared reference
- Positive direction: Direction relative to an identified frame or display
- Coordinate units: Declared unit; dimensionless; unspecified
- Coordinate domain: Declared interval or value set, including endpoint and periodicity conventions
- Scale mapping: Linear; logarithmic; piecewise; other specified mapping
- Inter-axis geometry: Declared angles, orthogonality, or basis relationships under a specified metric
- Interpretation readiness: Sufficiently specified for a stated operation; ambiguous; inconsistent
Plane XCT: no invented physical properties.
Recognition optional Filled
- A straight reference line, often with an arrowhead showing the positive direction.
- Tick marks with numbers along the line showing the scale.
- A label such as x, y or z, or a named quantity with its unit.
- Two or three such lines meeting at an origin, usually at right angles.
Capabilities and actions required Filled
- Associate a coordinate component with its reference, positive direction, and units.
- Read or assign a value using the declared coordinate-to-position mapping.
- Check whether a proposed value belongs to the axis's domain.
- Determine whether projection or component extraction is valid under the surrounding coordinate conventions.
- Convert units, reverse direction, or re-express coordinates when the required mapping is known.
- Flag missing conventions that prevent reliable interpretation or comparison.
Hazards and failure modes required Filled
- Swapped or reversed axes put objects, machines or points in the wrong place.
- Truncated or non-zero axes exaggerate small differences in charts.
- Mixing left-handed and right-handed systems mirrors geometry in models and robots.
- Unlabelled units on an axis lead to misreading of values by orders of magnitude.
Standards and interfaces required Filled
- ISO 80000-2, Quantities and units, Part 2: Mathematics, ISO, which covers coordinate systems and notation.
Context of use required Filled
- A coordinate axis provides a reference direction for expressing positions in geometry, maps, engineering drawings and spatial models.
- In robotics and measurement systems, axes support interpretation of locations and movements when the origin, units and coordinate conventions are known.
Sources Filled
- Wikidata item Q1783819: coordinate axis - identity and sense of the item
- Wikipedia: Coordinate axis - general description of the item
Open questions
- Does the registry intend coordinate axis to include chart axes, or only geometric axes within coordinate systems?
- How should this entry distinguish coordinate axes from coordinate lines and local coordinate basis directions in curvilinear systems?
- Are categorical chart guides instances of this thing, or should they belong to a neighbouring display-axis model?
- Which existing Vercy models own coordinate systems, basis vectors, scales, and reference frames, and does any already cover this concept?
- Which mathematical and visualisation references should establish the definitions and terminology used in a researched publication?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q1783819/spec.json