About Patterns

A pattern is a customized analysis schema object. When applying a pattern to a document (Word, Excel...), you apply a predefined structure analysis.

The pattern can also capture an identifier for elements of the document structure. Then the coverage view displays these identifiers. For example, a pattern can help identifying chapters in a Word document.

Note: A pattern analyzes a document and captures information, but do not modify the analyzed document.

This page discusses:

Concept

Traceability is possible when objects to be linked (for example, requirements) and links can be recognized. RFL requirements and links are captured natively. Other documents (Word, Excel, DOORS...) may not have clear formalism to identify requirements and links.

A pattern schema enables a customized recognition of traceability elements:

  • Nonintrusive support of specific formalism
  • Custom resources exploration based on RDF patterns. For more information, see RDF Standard below.
  • Custom rules to capture sections, requirements, and links.

Patterns use the following concepts:

  • Model validation (similar to XML Schema Definition)
  • Deep first search (transverse graph from root to children without cycles)
  • Pattern matching
  • Sequence matching
  • Regular expression matching

Description

Pattern Content

A pattern schema is the main document for a pattern conception.

A pattern schema contains definitions and patterns. You must create one definition as root, that is, the starting point of the analysis.

Patterns are used for various purposes: resource (with statement matching), sequence (with occurrences), choices, extraction rules (rules, analysis types...).

Here is a simplified pattern diagram.



Pattern object Usage Reference document
Pattern Schema See Creating a Pattern Schema Pattern Structure
Definition and Reference (to definition) See Inserting a Pattern Definition Pattern Structure
Choice, Occurrence, Sequence See Inserting a Pattern Choice, Sequence and Occurrence
Analysis Type, Setter, Rule, Field capture See Inserting a Pattern Capture Patterns
Statement, Resource See Inserting a Pattern Resource and Statement
Literal Value, Regular Expression See Inserting a Pattern Regular Expression and Literal Value

Pattern Display

Structure example


Color Code
Pattern Element Text Color Background Color
Root pattern definition White Dark Blue
Pattern definition White Blue
Analysis type White Green
For an analysis type: entity, link, and attribute Green White with a green border
Choice Black White (no background)
Occurrence Black Light gray
Rules Black Dark gray
Statement Black White with a black border
Variable Purple White with purple border
Resource, sequence Blue White with blue border
Empty Pattern White Red

RDF Standard

Patterns are based on the RDF (Resource Description Framework) standard. This standard is based on subject, predicate, object.

Commonly used predicates in Systems Traceability Dashboarding
Predicate Display in the statement pattern

http://www.w3.org/1999/02/22-rdf-syntax-ns#type

type

http://purl.org/dc/terms/title

title

http://purl.org/dc/terms/description

description

http://purl.org/dc/terms/hasPart

haspart (Child visible in Details only)

http://www.3ds.com/vocabularies/syc/treeChild

treechild
Finding predicates

To display its predicate, hover over a resource in the Properties panel, in the Detail section.

About Collaborative Lifecycle

You can share a pattern and transfer its ownership using the Collaborative Lifecycle app. For more information, see the Collaborative Lifecycle User's Guide.