Polyconic Projection Class¶
Polyconic as a class refers to those projections whose parallels are all non-concentric circular arcs, except for a straight equator, and the centers of these circles lie along a central axis.
Core Idea¶
Polyconic Projection Class is treated here as the recurring mathematics, logic, and statistics identity summarized by this source-grounded definition: Polyconic as a class refers to those projections whose parallels are all non-concentric circular arcs, except for a straight equator, and the centers of these circles lie along a central axis. Polyconic can refer either to a class of map projections or to a specific projection known less ambiguously as the American polyconic projection. Polyconic as a class refers to those projections whose parallels are all non-concentric circular arcs, except for a straight equator, and the.
Scope of Application¶
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Rectangular polyconic projection. Nicolosi globular projection—typically used to project a hemisphere into a circle; all meridians and parallels are arcs of circles.
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Rectangular polyconic projection. Most polyconic projections, when used to map the entire sphere, produce an "apple-shaped" map of the world.
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Polyconic projections. American polyconic projection—each parallel becomes a circular arc having true scale, the same scale as the central meridian.
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Rectangular polyconic projection. Van der Grinten projection—projects entire earth into one circle; all meridians and parallels are arcs of circles.
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Rectangular polyconic projection. A series of polyconic projections, each in a circle, was also presented by Hans Mauer in 1922, who also presented an equal-area polyconic in 1935.
Clarity¶
A clear use of Polyconic Projection Class names the carrier, the operative relation, and the conditions under which the source treats the identity as present. The minimal definition is Polyconic as a class refers to those projections whose parallels are all non-concentric circular arcs, except for a straight equator, and the centers of these circles lie along a central axis.
Manages Complexity¶
Polyconic Projection Class compresses multiple mathematics, logic, and statistics details into a stable diagnostic relation. The source shows both the central mechanism—another series by Georgiy Aleksandrovich Ginzburg appeared starting in 1949.—and the practical consequence—most polyconic projections, when used to map the entire sphere, produce an "apple-shaped" map of the world. This compression makes cases comparable while leaving parameters, conventions, exceptions, and evidential quality explicit.
Abstract Reasoning¶
- Type the carrier. Identify the mathematics, logic, and statistics entities to which the claim applies.
- State the relation. Use the source-grounded identity: Polyconic as a class refers to those projections whose parallels are all non-concentric circular arcs, except for a straight equator, and the centers of these circles lie along a central axis.
- Check operation and conditions. American polyconic projection—each parallel becomes a circular arc having true scale, the same scale as the central meridian.
- Demand recognition evidence.
Knowledge Transfer¶
Within the home domain. Knowledge about Polyconic Projection Class transfers literally when a new case preserves the same carrier type, relation, and recognition test. Nicolosi globular projection—typically used to project a hemisphere into a circle; all meridians and parallels are arcs of circles. Most polyconic projections, when used to map the entire sphere, produce an "apple-shaped" map of the world. Beyond the home domain. No canonical parent is asserted for Polyconic Projection Class.
Relationships to Other Abstractions¶
Current abstraction Polyconic Projection Class Domain-specific
Parents (1) — more general patterns this builds on
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Polyconic Projection Class is a kind of Projection Prime
The polyconic class consists of map projections with circular-arc parallels and a straight equator.
Hierarchy path (1) — routes to 1 parentless root
- Polyconic Projection Class → Projection → Abstraction
Neighborhood in Abstraction Space¶
Polyconic Projection Class sits in a sparse region of the domain-specific corpus (69th percentile for distinctiveness): few abstractions share its structure, so a faithful description tends to retrieve it precisely.
Family — Geometric Figures & Constructions (32 abstractions)
Nearest neighbors
- Vincenty's formulae — 0.85
- Perspective (graphical) — 0.84
- Supplementary Angles — 0.84
- Newton–Gauss line — 0.83
- Non-Archimedean geometry — 0.83
Computed from structural-signature embeddings · 2026-10-08