Geodesic Math and How to Use It

22 Tetrahedral Coordinates

22   Tetrahedral Coordinates

1Because its breakdowns entail an excessive number of different component lengths, a problem compounded by the high frequencies required to obtain anything acceptably spherical, the tetrahedron is of limited usefulness. Still, investigators may have a use for data. Class II Method 1 is recommended for study. It has orthogonal equators like the octahedron, permitting natural hemispheric truncation, and when so truncated provides large squarish openings at ground level. (0,0 is not at the zenith.)

2 The designer might also consider omitting some of the shorter struts that clutter the three-way vertices. So long as triangulation is preserved this will do no structural damage and greatly improve the symmetry.

3 Large families of intersecting equators—eight in the 4v Class I—permit numerous zenith locations and overhead symmetries. Two Class I tables provide for the following frequencies: 16,12,8,6,4,3. They cover one tetrahedron face, with comers at 0,0;0,arccos⁡−1∕3;120,arccos⁡1∕3.

4 Two Class II Method 1 tables provide for sixteen, twelve, eight, and six-frequency breakdowns. They cover the Class II triangle with vertices at 0,0;0,arccos⁡1∕3;120,arccos⁡1∕3. See Diagram 22.1 for the location of this triangle; twelve of them make a sphere.

5PIC

63v 6v 12v

7V

8e

90,0 0,0 0,0

1000.0000000

1100.0000000

12

131,0

1400.0000000

155.0511525

16

171,1

18120.0000000

195.0511525

201,0 2,0

2100.0000000

2211.4217537

23

242,1

2560.0000000

265.7681812

271,1 2,2

28120.0000000

2911.4217537

30

313,0

3200.0000000

3319.4712206

34

353,1

3630.0000000

3711.5369590

38

393,2

4090.0000000

4111.5369590

42

433,3

44120.0000000

4519.4712206

461,0 2,0 4,0

4700.0000000

4829.4962085

49

50*4,1

5119.1066054

5220.5141272

532,1 4,2

5460.0000000

5515.7931691

56

574,3

58100.8933946

5920.5141272

601,1 2,2 4,4

61120.0000000

6229.4962085

63

645,0

6500.0000000

6641.4729343

67

685,1

6913.8978863

7032.5125173

71

725,2

7340.8933947

7425.0658292

75

765,3

7779.1066054

7825.0658292

79

805,4

81106.1021138

8232.5125173

83

845,5

85120.0000000

8641.4729343

873,0 6,0

8800.0000000

8954.7356103

90

916,1

9210.8933947

9347.2058629

94C\J

950

96KO

9700

9830.0000000

9939.2315205

10260.0000000

10335.2643897

104*

105KO

106CM

107no

10890.0000000

10939.2315205

112109.1066053

11347.2058629

1143,3 6,6

115120.0000000

11654.7356103

11900.0000000

12067.9982863

1238.9482756

12463.0694073

12723.4132245

12857.0210379

13146.1021138

13251.8870735

13573.8978863

13651.8870735

13996.5867756

14057.0210380

143111.0517244

14463.0694073

147120.0000000

14867.9982863

1492,0 4,0 8,0

15000.0000000

15179.9750121

1547.5890895

15577.8296766

1564,1 8,2

15719.1066054

15875.0367825

16136.5867756

16272.0247162

1632,1 4,2 8,4

16460.0000000

16570.5287793

1665

16783.4132244

16872.0247162

1693v 6v 12v

1704>

1716

1724,3 8,6

173100.8933946

17475.0367825

177112.4109105

17877.8296766

1792,2 4,4 8,8

180120.0000000

18179.9750121

18400.0000000

18590.0000000

1886.587756

18990.0000000

19216.1021138

19390.0000000

19630.0000000

19790.0000000

20049.1066054

20190.0000000

20470.8933947

20590.0000000

20890.0000000

20990.0000000

212103.8978862

21390.0000000

216113.4132244

21790.0000000

220120.0000000

22190.0000000

2225,0 10,0

22300.0000000

22498.0494670

225

22610,1

2275.8175256

22899.3984525

2295,1 10,2

23013.8978863

231101.0958033

232

23310,3

23425.2849961

235103.0884761

2365,2 10,4

23740.8933947

238104.9632175

239

24010,5

24160.0000000

242105.7931691

2435,3 10,6

24479.1066054

245104.9632175

246

24710,7

24894.7150039

249103.0884761

2505,4 10,8

251106.1021138

252101.0958033

253

25410,9

255114.1824744

25699.3984525

2575,5 10,10

258120.0000000

25998.0494670

260

26111,0

26200.0000000

263104.4200681

264

26511,1

2665.2087191

267106.5150758

268

26911,2

27012.2163488

271109.0624559

272

27311,3

27421.7867893

275112.0017137

276

27711,4

27834.7150040

279114.9379827

280

28111,5

28251.0517245

283116.9305927

284

28511,6

28668.9482756

287116.9305927

288

28911,7

29085.2849961

291114.9379827

292

29311,8

29498.2132107

295112.0017137

296

29711,9

298107.7836512

299109.0624558

300

30111,10

302114.7912809

303106.5150758

304

30511,11

306120.0000000

307104.4200681

3083,0 6,0 12,0

30900.0000000

310109.4712206

311

31212,1

3134.7150040

314111.9343322

3156,1 12,2

31610.8933947

317114.8398925

318

31912,3

32019.1066054

321118.1255057

3223,1 6,2 12,4

32330.0000000

324121.4821541

325

32612,5

32743.8978863

328124.1908638

3296,3 12,6

33060.0000000

331125.2643897

332

33312,7

33476.1021138

335124.1908638

3363,2 6,4 12,8

33790.0000000

338121.4821541

339

340(Continued)

3413v

3426v

34312v

344V

345e

3466,5

34712,9

34812,10

349100.8933946

350109.1066053

351118.1255057

352114.8398925

3533v

3546v

35512v

356V

3576

3583,3

3596,6

36012,11

36112,12

362115.2849960

363120.0000000

364111.9343322

365109.4712206

366 TETRAHEDRON CLASS I COORDINATES: Frequencies 16, 8, 4

3674v 8v 16v

368V

3698

3700

371V

3720

3730

3740

3750

3760

37700.0000000

37800.0000000

38100.0000000

3823.6780516

385120.0000000

3863.6780516

3870

388CXI

3890

39000.0000000

3918.0494670

39460.0000000

3954.0446912

3961,1 2,2

397120.0000000

3988.0494670

40100.0000000

40213.2626760

40530.0000000

4067.7493664

40990.0000000

4107.7493664

413120.0000000

41413.2626760

4150

4160

417cxj

4180

41900.0000000

42019.4712206

42319.1066054

42413.1622883

4252,1 4,2

42660.0000000

42710.0249879

428n 4’3

429100.8933946

43013.1622883

4311,1 2,2 4,4

432120.0000000

43319.4712206

43600.0000000

43726.7972576

44013.8978863

44120.0124169

44440.8933947

44514.9632174

44879.1066054

44914.9632174

452106.1021138

45320.0124169

456120.0000000

45726.7972576

4583,0 6,0

45900.0000000

46035.2643897

46310.8933947

46428.3717844

4653,1 6,2

46630.0000000

46722.2076543

47060.0000000

47119.4712206

4723,2 6,4

47390.0000000

47422.2076543

477109.1066053

47828.3717844

4793,3 6,6

480120.0000000

48135.2643897

48400.0000000

48544.7106224

4888.9482756

48938.2169233

49223.4132245

49331.6513993

49646.1021138

49727.0171232

50073.8978863

50127.0171232

50496.5687756

50531.6513993

508111.0517244

50938.2169233

512120.0000000

51344.7106225

5144v 8v 16v

515_sL_

516a

5172,0 4,0 8,0

51800.0000000

51954.7356103

5227.5890895

52349.2169021

5244,1 8,2

52519.1066054

52643.0887231

52936.5867756

53037.6161120

5312,1 4,2 8,4

53260.0000000

53335.2643897

53683.4132244

53737.6161120

5384,3 8,6

539100.8933946

54043.0887232

543112.4109105

54449.2169021

5452,2 4,4 8,8

546120.0000000

54754.7356103

55000.0000000

55164.7605982

5546.5867756

55560.6661258

55816.1021138

55955.8091362

56230.0000000

56350.7684795

56649.1066054

56747.2058629

57070.8933947

57147.2058629

57490.0000000

57550.7684795

578103.8978862

57955.8091362

582113.4132244

58360.6661258

584

585’ 9,9

586120.0000000

58764.7605982

5885,0 10,0

58900.0000000

59074.2068310

591

59210,1

5935-8175256

59471.6832693

5955,1 10,2

59613.8978863

59768.5832860

598

59910,3

60025-2849961

60165.0620173

6025,2 10,4

60340.8933947

60461.8744943

605

60610,5

60760.0000000

60860.5037915

6095,3 10,6

61079.1066054

61161.8744943

612

61310,7

61494.7150039

61565.0620173

6165,4 10,8

617106.1021138

61868.5832860

619

62010,9

621114.1824744

62271.6832693

6235,5 10,10

624120.0000000

62574.2068310

626

62711,0

62800.0000000

62982.6739631

630

63111,1

6325.2087191

63381.5673284

634

63511,2

63612.2163488

63780.1975692

638

63911,3

64021.7867893

64178.5782463

642

64311,4

64434.7150040

64576.9115239

646

64711,5

64851.0517245

64975-7482449

650

65111,6

65268.9482756

65375.7482449

654

65511,7

65685.2849961

65776.9115239

658

65911,8

66098.2132107

66178.5782463

662

66311,9

664107.7836512

66580.1975692

6664v 8v 16v

667V

668e

66911,10

670114.7912809

67181.5673284

67211,11

673120.0000000

67482.6739631

6753,0 6,0 12,0

67600.0000000

67790.0000000

67812,1

6794.7150040

68090.0000000

6816,1 12,2

68210.8933947

68390.0000000

684

68512,3

68619.1066054

68790.0000000

6883,1 6,2 12,4

68930.0000000

69090.0000000

691

69212,5

69343.8978863

69490.0000000

6956,3 12,6

69660.0000000

69790.0000000

698

69912,7

70076.1021138

70190.0000000

7023,2 6,4 12,8

70390.0000000

70490.0000000

705

70612,9

707100.8933946

70890.0000000

7096,5 12,10

710109.1066054

71190.0000000

71212,11

713115.2849960

71490.0000000

7153,3 6,6 12,12

716120.0000000

71790.0000000

718

71913,0

72000.. 0000000

72196.2085447

722

72313,1

7244.3066191

72596.9911553

726

72713,2

7289.8264298

72997.9328899

730

73113,3

73216.9960881

73399.0406311

734

73513,4

73626.3295035

737100.2634279

738

73913,5

74038.2132107

741101.4217537

742

74313,6

74452.4109105

745102.1703234

746

74713,7

74867.5890895

749102.1703234

750

75113,8

75281.7867893

753101.4217537

754

75513,9

75693.6704965

757100.2634279

75813,10

759103.0039H9

76099.0406311

761

76213,11

763110.1735702

76497.9328899

76513,12

766115.6933809

76796.9911553

768

76913 ,’13

770120.0000000

77196.2085447

7727,0 14,0

77300.0000000

774101.4217537

775

77614,1

7773.9632350

778102.7203545

7797,1 14,2

7808.9482756

781104.2517550

782

78314,3

78415.2953443

785106.0231797

7867,2 14,4

78723.4132245

788107.9752839

789

79014,5

79133.6704965

792109.9074988

7937,3 14,6

79446.1021138

795111.4167141

796

79714,7

79860.0000000

799112.0017137

8007,4 14,8

80173.8978863

802111.4167141

803

80414,9

80586.3295035

806109.9074988

8077,5 14,10

80896.5867756

809107.9752839

810

81114,11

812104.7046557

813106.0231797

8147,6 14,12

815111.0517244

816104.2517550

81714,13

818116.0367651

819102.7203545

8207,7 14,14

821120.0000000

822101.4217537

823

82415,0

82500.0000000

826105.7931690

827

82815,1

8293.6704965

830107.4127302

8314v 8v 16v

832.V

833e

834

83515,2

83615,3

83715,4

83815,5

83915,6

84015,7

84115,8

84215,9

84315,10

84415,11

84515,12

84615,13

84715.14

84815,15

8498.2132107

85013.8978863

85121.0517244

85230.0000000

85340.8933947

85453.4132245

85566.5867755

85679.1066054

85790.0000000

85898.9482756

859106.1021138

860111.7867893

861116.3295035

862120.0000000

863109.2863254

864111.4167140

865113.7466788

866116.1001388

867118.1255057

868119.3338742

869119.3338743

870118.1255057

871116.1001388

872113.7466788

873111.4167140

874109.2863254

875107.4127301

876105.7931691

8774,0 8,0 16,0

878

879’ 16,1

8808,1 16,2

881

88216,3

8834,1 8,2 16,4

884

88516,5

8868,3 16,6

887

88816,7

8894,2 8,4 16,8

890

89116,9

8928,5 16,10

893

89416,11

8954,3 8,6 16,12

896

89716,13

8988,7 16,14

899

90016,15

9014,4 8,8 16,16

90200.0000000

9033.4179811

9047.5890895

90512.7305278

90619.1066054

90726.9955084

90836.5867756

90947.7836512

91060.0000000

91172.2163488

91283.4132244

91393.0044916

914100.8933946

915107.2694722

916112.4109105

917116.5820189

918120.0000000

919109.4712206

920111.2776255

921113.3320386

922115.6320697

923118.1255057

924120.6679177

925122.9789620

926124.6481469

927125.2643897

928124.6481469

929122.9789620

930120.6679177

931118.1255057

932115.6320697

933113.3320386

934III.2776255

935109.4712206

9368v 16v

937V

9380

9390,0 0,0

94000.0000000

94100.0000000

9421,0

94300.0000000

9447.3260370

9451,1

946120.0000000

9477.3260370

9481,0 2,0

94900.0000000

95015.7931690

9512,1

95260.0000000

9538.0494670

9541,1 2,2

955120.0000000

95615.7931690

9573,0

95800.0000000

95925.2394018

9603,1

96130.0000000

96215.2251570

9633,2

96490.0000000

96515.2251570

9663,3

967120.0000000

96825.2394018

9692,0 4,0

97000.0000000

97135.2643897

9724,1

97319.1066054

97425.0658292

9752,1 4,2

97660.0000000

97719.4712206

9784,3

979100.8933946

98025.0658292

9812,2 4,4

982120.0000000

98335.2643897

9845,0

98500.0000000

98645.2893775

9875,1

98813.8978863

98936.0707687

9905,2

99140.8933947

99228.1255057

9935,3

99479.1066054

99528.1255057

9965,4

997106.1021138

99836.0707687

9995,5

1000120.0000000

100145.2893775

10028v 16v

1003V

10046

10053,0 6.0

100600.0000000

100754.7356103

10086,1

100910.8933947

101047.2058629

10113,1 6,2

101230.0000000

101339.2315205

10146,3

101560.0000000

101635.2643897

10173,2 6,4

101890.0000000

101939.2315205

10206,5

1021109.1066053

102247.2058629

10233,3 6,6

1024120.0000000

102554.7356103

10267,0

102700.0000000

102863.2027424

10297,1

10308.9482756

103157.5844268

10327,2

103323.4132245

103450.9542458

10357,3

103646.1021138

103745.5617593

10387,4

103973.8978863

104045.5617593

10417,5

104296.5867756

104350.9542458

10447,6

1045111.0517244

104657.5844268

10477,7

1048120.0000000

104963.2027424

10504,0 8,0

105100.0000000

105270.5287793

10538,1

10547.5890895

105566.6679614

10564,1 8,2

105719.1066054

105861.8744943

10598,3

106036.5867756

106157.0210380

10624,2 8,4

106360.0000000

106454.7356103

10658,5

106683.4132244

106757.0210380

10684,3 8,6

1069100.8933946

107061.8744943

10718,7

1072112.4109105

107366.6679614

10744,4 8,8

1075120.0000000

107670.5287793

10776v

107812v

1079V

10806

10810,0

10820,0

108300.0000000

108400.0000000

10851,0

108600.0000000

108710.0249879

10881,1

1089120.0000000

109010.0249879

10911,0

10922,0

109300.0000000

109422.0017137

10952,1

109660.0000000

109711.4217537

10981,1

10992,2.

1100120.0000000

110122.0017137

11023,0

110300.0000000

110435.2643897

11053,1

110630.0000000

110722.2076543

11083,2

110990.0000000

111022.2076543

11113,3

1112120.0000000

111335.2643897

11142,0

11154,0

111600.0000000

111748.5270657

11184,1

111919.1066054

112036.8086651

11212,1

11224,2

112360.0000000

112429.4962085

11254,3

1126100.8933946

112736.8086651

11284,4

1129120.0000000

113048.5270657

1131 TETRAHEDRON CLASS II COORDINATES: Frequencies 12, 6

11326v

113312v

1134V

1135e

11365,0

113700.0000000 ’

113860.5037915

11395,1

114013.8978863

114151.8870735

11425,2

114340.8933947

114443.0887231

11455,3

114679.1066054

114743.0887231

11485,4

1149106.1021138

115051.8870735

11515,5

1152120.0000000

115360.5037915

11543,0

11556,0

115600.0000000

115770.5287793

11586,1

115910.8933947

116065.1601075

11613,1

11626,2

116330.0000000

116458.5178459

11656,3

116660.0000000

116754.7356103

11683,2

11696,4

117090.0000000

117158.5178459

11726,5

1173109.1066053

117465.1601076

11753,3

11766,6

1177120.0000000

117870.5287793