PointInJourneyPattern¶

Status¶

Normative

Definition¶

A PointInJourneyPattern represents one ordered point within a JourneyPattern.

It identifies the position of a point in the planned operational sequence of a JourneyPattern.

A PointInJourneyPattern is distinct from the physical location itself.

Multiple PointInJourneyPattern instances may reference the same PublicTransportStop when a JourneyPattern visits that stop more than once.

Identity¶

The semantic identity of a PointInJourneyPattern is established by:

the JourneyPattern to which it belongs; and
its position within that JourneyPattern.

A PointInJourneyPattern remains the same semantic instance when:

descriptive information changes;
multiple ServiceJourneys use the same JourneyPattern; or
different OperatingDays use the same JourneyPattern.

Changing the order of points normally establishes a different PointInJourneyPattern.

Within a JourneyPattern, the occurrence discriminator shall identify the ordered point independently of the referenced PublicTransportStop.

Where the same PublicTransportStop is visited more than once, each visit shall have a distinct PointInJourneyPattern identity.

For GTFS stop_times.txt, stop_sequence shall be used as the primary occurrence discriminator unless an applicable profile defines a more stable equivalent. The GTFS stop_id identifies the referenced PublicTransportStop; it shall not by itself identify the PointInJourneyPattern occurrence.

A PassingEvent shall use the applicable PointInJourneyPattern identity, sequence, or an equivalent profile-defined discriminator when required to distinguish repeated visits to the same stop.

Implementation-specific identifier construction is defined by the relevant mapping specification.

Motivation¶

Public transport operations require an ordered representation of the planned journey.

Physical stops alone cannot express:

visit order;
repeated visits to the same stop;
timing points;
operational control points; or
non-stopping operational locations.

PointInJourneyPattern provides this ordered operational structure.

Characteristics¶

A PointInJourneyPattern:

belongs to exactly one JourneyPattern;
occupies one position in the ordered sequence;
may reference one PublicTransportStop;
may represent a timing point;
may represent a non-stopping operational point; and
may be referenced by planned and monitored timing information.

Relationships¶

JourneyPattern¶

Each PointInJourneyPattern belongs to one JourneyPattern.

Its sequence within that JourneyPattern contributes to the planned operational pattern.

PublicTransportStop¶

A PointInJourneyPattern may reference one PublicTransportStop.

The same PublicTransportStop may be referenced by multiple PointInJourneyPattern instances, including repeated visits within the same JourneyPattern.

PassingEvent¶

A PointInJourneyPattern may be referenced by zero or more PassingEvent entities.

Each associated PassingEvent represents an operational event at the ordered journey-pattern point.

Scheduled, predicted, and observed times are properties of the associated PassingEvent, not of the PointInJourneyPattern itself.

Typical Properties¶

Typical semantic properties include:

identifier
sequence
stop
timingPoint
boardingAllowed
alightingAllowed
requestStop

PassingEvent timing values are not embedded as properties of the PointInJourneyPattern.

The presence of a typical property does not make it mandatory.

This semantic model does not prescribe implementation-specific property names, value encodings, or data structures.

Conformance Requirements¶

A conforming PointInJourneyPattern shall include:

a stable semantic identity;
one relationship to the applicable JourneyPattern;
one position or sequence discriminator within that JourneyPattern.

The following conditional requirements apply:

a PublicTransportStop relationship shall be present when the ordered point represents a physical passenger stop;
repeated visits to the same PublicTransportStop within one JourneyPattern shall be represented by distinct PointInJourneyPattern instances;
boarding, alighting, timing-point, and request-stop properties shall be present only when those operational semantics are known or required by the applicable profile;
a PassingEvent associated with the point shall reference the same operational occurrence within the applicable monitored journey.

The following information is optional unless required by an applicable profile:

a PublicTransportStop relationship;
timing-point indication;
boarding permission;
alighting permission;
request-stop indication;
source-specific identifiers.

Scheduled, predicted, and observed event times shall be represented by associated PassingEvent entities and shall not be embedded as temporal properties of the PointInJourneyPattern.

Origin¶

This semantic concept is adopted primarily from:

Transmodel — POINT IN JOURNEY PATTERN

SCRA Schema adopts the Transmodel definition without changing its fundamental meaning.

Mapping Guidance¶

Typical mappings include:

Source	Semantic Mapping
Transmodel `POINT IN JOURNEY PATTERN`	PointInJourneyPattern
GTFS `stop_times.txt` stop sequence	Ordered PointInJourneyPattern
GTFS `stop_id`	Reference to PublicTransportStop

Each GTFS stop_times.txt record normally contributes one PointInJourneyPattern within the corresponding JourneyPattern.

The stop_sequence establishes the ordering and occurrence discriminator of the PointInJourneyPattern instances. The stop_id resolves the referenced PublicTransportStop.

These mappings shall preserve repeated-stop occurrences as distinct PointInJourneyPattern instances.

The mapping table remains informative; the identity and occurrence rules in the normative sections above are binding.