Naming Convention Overview

This naming system provides a uniform way to label geometric objects associated with three types of quadrangular reference systems. Each label consists of a prefix indicating the reference system and a suffix indicating the type of geometric item, optionally followed by an occurrence number.

Prefixes: Reference Systems

Each prefix specifies the underlying quadrangular structure:

• QA — Quadrangle defined by four reference points
• QL — Quadrangle defined by four reference lines
• QG — Quadrangle defined by a 4‑gon (Quadrigon)

Special Cases

• QAc — Cyclic Quadrangle: four reference points lying on a reference circle
• QLt — Tangential Quadrilateral: four reference lines tangent to a reference circle

Suffixes: Geometric Item Types

Each suffix identifies the nature of the geometric object:

• –i — Documentation page (i = 1, 2, 3, …)
• –P — Point
• –L — Line
• –Ci — Circle
• –Co — Conic
• –Cu — Cubic
• –Qu — Quartic
• –Tf — Transformation
• –Tr — Triangle

Sequence Numbers

Every suffix is followed by a sequence number (e.g., P1, Cu3, Tr2). If multiple items of the same type occur, the suffix may be preceded by a multiplicity number (2, 3, …), indicating how many such items appear.

Examples

• QA‑1 — First documentation page on a Quadrangle
• QA‑P1 — First Quadrangle Point: the QA Centroid
• QA‑4Tr1 — The four component triangles of a Quadrangle
• QL‑2P1 — First bicentric pair of points related to a Quadrilateral (the Plücker Pair)
• QL‑27Qu1 — First occurrence of a set of 27 Quartics related to a Quadrilateral (Morley’s Multiple Cardioids)
• QL‑Tr2 — Second triangle associated with a Quadrilateral (the QL NPC Triangle)
• QG‑Cu1 — First Cubic associated with a Quadrigon (the Van Aubel Cubic)

Estimated human page views: 17766