Scalar Quantity

• CURIE: gmeow:ScalarQuantity
• IRI: https://blackcatinformatics.ca/gmeow/ScalarQuantity
• Category: class
• Defined by: gmeow:slices/observations
• Box roles: TBox role (What is this?)

A scalar numeric value with a unit, determinacy model, and granularity — the entity-valued wrapper for literal observation results (temperatures, distances, counts, probabilities). Keeps gmeow:observationResult uniformly entity-valued: the scalar literal lives here, not on the observation directly.

Structure

Subclass of: gmeow:Entity, gufo:Object

Practical Pattern

Use gmeow:ScalarQuantity as a specialized kind of gmeow:Entity, gufo:Object. Add statement metadata or a standpoint when the assertion needs provenance, confidence, or vantage.

Example Snippets

These snippets are generated from canonical slice examples and trimmed to the Turtle blocks where this term appears.

Temperature Reading

• Source: slices/core/observations/examples/temperature-reading.ttl
• Examples catalog: open in catalog#example-slices-core-observations-examples-temperature-reading

# SPDX-FileCopyrightText: 2026 Blackcat Informatics® Inc. <paudley@blackcatinformatics.ca>
# SPDX-License-Identifier: CC-BY-4.0
#
# Worked example: a measurement is a reified Observation ( P11). A
# gmeow:Measurement records WHAT was observed (gmeow:observedFeature), HOW
# (gmeow:observationMethod), and from WHERE (gmeow:vantage — the sensor). Its
# result is NOT a bare number on the observation: the scalar lives in an
# entity-valued gmeow:ScalarQuantity wrapper that bundles the value with its UNIT
# and uncertainty, so a temperature is never asserted free-floating (P11 — every
# value carries its frame). The unit is aligned to QUDT by reference (P5).
@prefix gmeow: <https://blackcatinformatics.ca/gmeow/> .
@prefix ex:    <https://blackcatinformatics.ca/gmeow/examples/observations/> .
@prefix xsd:   <http://www.w3.org/2001/XMLSchema#> .

# --- The result wrapper: value + unit + uncertainty, not a bare literal.
ex:temp a gmeow:ScalarQuantity ;
    gmeow:quantityValue       "22.5"^^xsd:decimal ;
    gmeow:quantityUncertainty "0.1"^^xsd:decimal ;
    gmeow:hasUnit             <http://qudt.org/vocab/unit/DEG_C> .

Spatial Bins

• Source: slices/extensions/aggregation/examples/spatial-bins.ttl
• Examples catalog: open in catalog#example-slices-extensions-aggregation-examples-spatial-bins

# The result is a scalar with its unit (a Quantity must declare exactly one unit,
# P11); a count of persons-per-household is the dimensionless QUDT number unit.
ex:avgHouseholdSize a gmeow:ScalarQuantity ;
    gmeow:quantityValue "2.4"^^xsd:decimal ;
    gmeow:hasUnit       <http://qudt.org/vocab/unit/NUM> .

Common Companion Terms

gmeow:Entity, gmeow:MeasuredValue, gmeow:Quantity, gmeow:hasDeterminacy, gmeow:hasGranularity, gmeow:hasReferenceFrame, gmeow:hasUnit, gmeow:assertedAt, gmeow:confidence, gmeow:recordedNoLaterThan

Cross-Cutting Concerns

frames and units, provenance and evidence

Projects To

External Equivalences

Equivalent or closely aligned targets: loinc, obscore, om, sosa

Linkages

Generated from the canonical mapping DSL. SSSOM files are the generated public interchange form for term equivalences.

Term Equivalences

Projection Coverage

Usage Advice

Use when

• Use to wrap a literal scalar reading — temperature, distance, count, probability — as an entity so gmeow:observationResult stays uniformly entity-valued and the value travels with its unit, determinacy, and granularity.

Avoid when

• Avoid hanging the bare literal on the observation directly (wrap it here) and avoid using it for money (use gmeow:MonetaryAmount, whose currency frame is required); for the domain-neutral name prefer the equivalent gmeow:Quantity / gmeow:MeasuredValue.

How to use

• Mint the wrapper, set gmeow:quantityValue (and gmeow:quantityUncertainty), name gmeow:hasUnit and gmeow:hasDeterminacy, and link it back with gmeow:isResultOf so it inherits the observation's reference frame via the property chain.

Examples

• ex:temp22 a gmeow:ScalarQuantity; gmeow:quantityValue 22.5; gmeow:hasUnit qudt:DEG_C.