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67:. The projection was designed to achieve a number of desirable characteristics, namely symmetry of component maps (octants), scalability allowing the map to continue to work well even at high resolution, uniformity of
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91:, 10,000 km lengths for each of its octants' three main joined edges, and an M-shape Master-Map profile. The resulting map comprises 8 octants. Each octant is an
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The Cahill–Keyes projection was designed with four fundamental considerations in mind: visual fidelity to a globe, proportional
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divides each half-octant into twelve zones, each of which has different formulae for coordinate calculations.
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99:, and the other two run along meridians. The total length of each side is 10,043 km. The inner
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107:. Each 1° and 5° "tile" is proportional to each other. The specific process for constructing the
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Diagram by Duncan Webb showing the construction of one octant of a Cahill–Keyes projection
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172:"Polyhedral Projections Improve the Accurately of Mapping the Earth on a 2D Surface"
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in 1975. The projection is a refinement of an earlier 1909 projection by
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195:"Get to Know a Projection: Gene Keyes' 40-Year Quest for the Perfect Map"
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The Cahill–Keyes projection with Tissot's indicatrix of deformation.
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243:"Cahill-Keyes Octant Graticule: Principles and Specifications"
222:"Notes on Re-designing B.J.S. Cahill's Butterfly World Map"
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with three segments per side. One side runs along the
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Example of the projection used by The New York Times
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Gene Keyes's Cahill-Keyes and Cahill resource index
43:2012 by Duncan Webb using Cahill–Keyes projection.
268:D3.js Implementation of Cahill–Keyes Projection
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1385:Map projection of the tri-axial ellipsoid
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16:Polyhedral compromise map projection
193:Stockton, Nick (December 9, 2013).
170:Lobner, Peter (December 23, 2016).
14:
220:Keyes, Gene (December 30, 2009).
1328:Quadrilateralized spherical cube
1008:Quadrilateralized spherical cube
174:. The Lyncean Group of San Diego
917:Lambert cylindrical equal-area
23:Cahill–Keyes map of the world.
1:
1365:Interruption (map projection)
1003:Lambert azimuthal equal-area
799:Guyou hemisphere-in-a-square
789:Adams hemisphere-in-a-square
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39:Political World Map for
804:Lambert conformal conic
136:List of map projections
49:Cahill–Keyes projection
937:Tobler hyperelliptical
550:Tobler hyperelliptical
476:Space-oblique Mercator
84:
44:
32:
24:
103:converge towards the
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38:
30:
22:
1313:Cahill–Keyes M-shape
1173:Chamberlin trimetric
146:Bernard J. S. Cahill
93:equilateral triangle
1380:Tissot's indicatrix
1281:Central cylindrical
922:Smyth equal-surface
824:Transverse Mercator
673:General perspective
428:Smyth equal-surface
380:Transverse Mercator
1333:Waterman butterfly
1183:Miller cylindrical
814:Peirce quincuncial
709:Lambert equal-area
461:Gall stereographic
247:Gene Keyes Website
85:
59:first proposed by
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605:Lambert conformal
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495:Pseudocylindrical
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151:Octant projection
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1308:Cahill Butterfly
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1226:Goode homolosine
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1112:(Mecca or Qibla)
993:Goode homolosine
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535:Goode homolosine
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385:Oblique Mercator
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1410:Map projections
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1198:Van der Grinten
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1153:By construction
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1042:Equirectangular
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927:Trystan Edwards
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723:Pseudoazimuthal
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573:Winkel I and II
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466:Gall isographic
456:Equirectangular
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433:Trystan Edwards
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563:Kavrayskiy VII
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309:Map projection
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257:External links
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65:Bernard Cahill
57:map projection
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1268:Stereographic
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1208:Winkel tripel
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615:Pseudoconical
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1263:Orthographic
794:Gauss–Krüger
686:Orthographic
481:Web Mercator
375:Gauss–Krüger
249:, 2010-08-20
246:
241:Gene Keyes,
237:
225:. Retrieved
215:
203:. Retrieved
201:. Condé Nast
198:
188:
176:. Retrieved
165:
141:Dymaxion map
86:
75:Construction
48:
46:
1241:Perspective
1029:some aspect
1013:Strebe 1995
988:Equal Earth
907:Gall–Peters
889:Cylindrical
704:Equidistant
600:Equidistant
530:Equal Earth
413:Gall–Peters
357:Cylindrical
227:January 22,
205:January 22,
178:January 22,
121:Cartography
55:compromise
1303:AuthaGraph
1295:Polyhedral
1165:Compromise
1093:Loximuthal
1085:Loxodromic
1047:Sinusoidal
897:Balthasart
874:Sinusoidal
851:Sinusoidal
834:Equal-area
545:Sinusoidal
503:Equal-area
403:Balthasart
395:Equal-area
368:-conformal
345:By surface
157:References
61:Gene Keyes
53:polyhedral
1375:Longitude
1203:Wagner VI
1052:Two-point
983:Eckert VI
978:Eckert IV
973:Eckert II
950:Mollweide
945:Collignon
912:Hobo–Dyer
866:Bottomley
781:Conformal
769:By metric
660:Azimuthal
633:Polyconic
628:Bottomley
568:Wagner VI
540:Mollweide
525:Eckert VI
520:Eckert IV
515:Eckert II
510:Collignon
418:Hobo–Dyer
126:World map
109:graticule
101:meridians
1404:Category
1370:Latitude
1355:See also
1318:Dymaxion
1258:Gnomonic
1193:Robinson
1098:Mercator
1075:Gnomonic
1067:Gnomonic
902:Behrmann
809:Mercator
681:Gnomonic
663:(planar)
638:American
408:Behrmann
366:Mercator
115:See also
89:geocells
69:geocells
1231:HEALPix
1130:Littrow
741:Wiechel
643:Chinese
587:Conical
451:Central
446:Cassini
423:Lambert
320:History
97:equator
1250:Planar
1218:Hybrid
1125:Hammer
1057:Werner
998:Hammer
963:Albers
879:Werner
856:Werner
736:Hammer
731:Aitoff
650:Werner
595:Albers
471:Miller
330:Portal
1120:Craig
1037:Conic
843:Bonne
623:Bonne
199:Wired
51:is a
1323:ISEA
325:List
229:2020
207:2020
180:2020
105:pole
47:The
1406::
245:,
197:.
41:CE
301:e
294:t
287:v
231:.
209:.
182:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
