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Constants for Reference Ellipsoids used for Datum Transformations

The constants were calculated using Java double precision (64 bit IEEE 754). The precision is only accurate for a few decimal places. Use at your own risk.


semi-major axis             (a)
semi-minor axis             (b)
flattening                  (f)   = (a-b)/a
flattening inverse          (f-1)  = (1/f)
first eccentricity          (e)   = sqrt(1-(b2/a2))
first eccentricity squared  (e2)  = (a2-b2)/a2
second eccentricity         (e`)  = sqrt((a2/b2)-1)
second eccentricity squared (e`2) = (a2-b2)/b2

AIRY 1830
AUSTRALIAN 1965
BESSEL 1841
BESSEL 1841 NAMIBIA
CLARKE 1866
CLARKE 1880
EVEREST 1830 INDIA
EVEREST 1830 MALAYSIA
EVEREST 1956 INDIA
EVEREST 1964 MALAYSIA & SINGAPORE
EVEREST 1969 MALAYSIA
EVEREST PAKISTAN
FISHER 1960
GRS 80
HELMERT 1906
HOUGH 1906
INDONESIAN 1974
INTERNATIONAL 1924
KRASSOVSKY 1940
MODIFIED AIRY
SOUTH AMERICAN 1969
WGS 72
WGS 84

Ellipsoid [AIRY 1830]
  Semi-Major Axis (Equatorial Radius)..[6377563.396]
  Semi-Minor Axis (Polar Radius).......[6356256.909]
  Flattening...........................[0.00334085067870327]
  Flattening Inverse...................[299.32496126649505]
  First Eccentricity...................[0.0816733743281685]
  First Eccentricity Squared...........[0.006670540074149084]
  Second Eccentricity..................[0.08194714751155018]
  Second Eccentricity Squared..........[0.006715334985279728]

Ellipsoid [AUSTRALIAN 1965] Semi-Major Axis (Equatorial Radius)..[6378160.0] Semi-Minor Axis (Polar Radius).......[6356774.719] Flattening...........................[0.003352891899858333] Flattening Inverse...................[298.249997276158] First Eccentricity...................[0.08182018036905428] First Eccentricity Squared...........[0.006694541915624534] Second Eccentricity..................[0.08209543749645103] Second Eccentricity Squared..........[0.006739660857733726]
Ellipsoid [BESSEL 1841] Semi-Major Axis (Equatorial Radius)..[6377397.155] Semi-Minor Axis (Polar Radius).......[6356078.963] Flattening...........................[0.0033427731536659813] Flattening Inverse...................[299.15281535132334] First Eccentricity...................[0.0816968308747341] First Eccentricity Squared...........[0.006674372174974933] Second Eccentricity..................[0.08197084080074579] Second Eccentricity Squared..........[0.006719218741581313]
Ellipsoid [BESSEL 1841 NAMIBIA] Semi-Major Axis (Equatorial Radius)..[6377483.865] Semi-Minor Axis (Polar Radius).......[6356165.383] Flattening...........................[0.003342773176894559] Flattening Inverse...................[299.152813272542] First Eccentricity...................[0.0816968311581122] First Eccentricity Squared...........[0.006674372221277079] Second Eccentricity..................[0.08197084108698455] Second Eccentricity Squared..........[0.006719218788507778]
Ellipsoid [CLARKE 1866] Semi-Major Axis (Equatorial Radius)..[6378206.4] Semi-Minor Axis (Polar Radius).......[6356583.8] Flattening...........................[0.0033900753039287908] Flattening Inverse...................[294.9786982138982] First Eccentricity...................[0.0822718542230039] First Eccentricity Squared...........[0.006768657997291184] Second Eccentricity..................[0.0825517107388772] Second Eccentricity Squared..........[0.006814784945915172]
Ellipsoid [CLARKE 1880] Semi-Major Axis (Equatorial Radius)..[6378249.145] Semi-Minor Axis (Polar Radius).......[6356514.87] Flattening...........................[0.003407561308111843] Flattening Inverse...................[293.4650060791153] First Eccentricity...................[0.08248339919132311] First Eccentricity Squared...........[0.0068035111421552025] Second Eccentricity..................[0.08276542745958347] Second Eccentricity Squared..........[0.006850115982567657]
Ellipsoid [EVEREST 1830 INDIA] Semi-Major Axis (Equatorial Radius)..[6377276.345] Semi-Minor Axis (Polar Radius).......[6356075.413] Flattening...........................[0.0033244493186534527] Flattening Inverse...................[300.8016980102568] First Eccentricity...................[0.08147298125166744] First Eccentricity Squared...........[0.0066378466740345775] Second Eccentricity..................[0.08174473748851525] Second Eccentricity Squared..........[0.0066822021070661935]
Ellipsoid [EVEREST 1830 MALAYSIA] Semi-Major Axis (Equatorial Radius)..[6377298.556] Semi-Minor Axis (Polar Radius).......[6356097.55] Flattening...........................[0.003324449343845343] Flattening Inverse...................[300.80169573085277] First Eccentricity...................[0.0814729815598449] First Eccentricity Squared...........[0.006637846724250804] Second Eccentricity..................[0.08174473779978614] Second Eccentricity Squared..........[0.0066822021579557725]
Ellipsoid [EVEREST 1956 INDIA] Semi-Major Axis (Equatorial Radius)..[6377301.243] Semi-Minor Axis (Polar Radius).......[6356100.228] Flattening...........................[0.0033244493543833783] Flattening Inverse...................[300.8016947773539] First Eccentricity...................[0.08147298168875934] First Eccentricity Squared...........[0.006637846745256864] Second Eccentricity..................[0.08174473792999415] Second Eccentricity Squared..........[0.0066822021792435045]
Ellipsoid [EVEREST 1964 MALAYSIA & SINGAPORE] Semi-Major Axis (Equatorial Radius)..[6377304.063] Semi-Minor Axis (Polar Radius).......[6356103.039] Flattening...........................[0.003324449295589469] Flattening Inverse...................[300.8017000971244] First Eccentricity...................[0.08147298096952207] First Eccentricity Squared...........[0.006637846628060143] Second Eccentricity..................[0.08174473720353695] Second Eccentricity Squared..........[0.006682202060475285]
Ellipsoid [EVEREST 1969 MALAYSIA] Semi-Major Axis (Equatorial Radius)..[6377295.664] Semi-Minor Axis (Polar Radius).......[6356094.668] Flattening...........................[0.0033244492833663726] Flattening Inverse...................[300.8017012030905] First Eccentricity...................[0.08147298081999425] First Eccentricity Squared...........[0.006637846603695205] Second Eccentricity..................[0.08174473705250837] Second Eccentricity Squared..........[0.006682202035783637]
Ellipsoid [EVEREST PAKISTAN] Semi-Major Axis (Equatorial Radius)..[6377309.613] Semi-Minor Axis (Polar Radius).......[6356109.571] Flattening...........................[0.003324292418982392] Flattening Inverse...................[300.81589522323446] First Eccentricity...................[0.08147106184331902] First Eccentricity Squared...........[0.006637533917877878] Second Eccentricity..................[0.08174279880970892] Second Eccentricity Squared..........[0.006681885157244453]
Ellipsoid [FISHER 1960] Semi-Major Axis (Equatorial Radius)..[6378155.0] Semi-Minor Axis (Polar Radius).......[6356773.32] Flattening...........................[0.003352329944944847] Flattening Inverse...................[298.2999932652668] First Eccentricity...................[0.08181333493893231] First Eccentricity Squared...........[0.006693421773829873] Second Eccentricity..................[0.08208852275188877] Second Eccentricity Squared..........[0.006738525567587472]
Ellipsoid [GRS 80] Semi-Major Axis (Equatorial Radius)..[6378137.0] Semi-Minor Axis (Polar Radius).......[6356752.3141] Flattening...........................[0.0033528106875095227] Flattening Inverse...................[298.2572215381486] First Eccentricity...................[0.08181919111988833] First Eccentricity Squared...........[0.006694380035512838] Second Eccentricity..................[0.08209443822977103] Second Eccentricity Squared..........[0.0067394967882615795]
Ellipsoid [HELMERT 1906] Semi-Major Axis (Equatorial Radius)..[6378200.0] Semi-Minor Axis (Polar Radius).......[6356818.17] Flattening...........................[0.0033523298109184524] Flattening Inverse...................[298.3000051913226] First Eccentricity...................[0.08181333330622664] First Eccentricity Squared...........[0.006693421506675721] Second Eccentricity..................[0.08208852110265381] Second Eccentricity Squared..........[0.006738525296820739]
Ellipsoid [HOUGH 1906] Semi-Major Axis (Equatorial Radius)..[6378270.0] Semi-Minor Axis (Polar Radius).......[6356794.343] Flattening...........................[0.0033670034351006867] Flattening Inverse...................[296.99999399320365] First Eccentricity...................[0.0819918908067705] First Eccentricity Squared...........[0.0067226701580694265] Second Eccentricity..................[0.08226889044349586] Second Eccentricity Squared..........[0.006768170334803944]
Ellipsoid [INDONESIAN 1974] Semi-Major Axis (Equatorial Radius)..[6378160.0] Semi-Minor Axis (Polar Radius).......[6356774.504] Flattening...........................[0.0033529256086395256] Flattening Inverse...................[298.2469988070381] First Eccentricity...................[0.08182059097282252] First Eccentricity Squared...........[0.0066946091071419115] Second Eccentricity..................[0.08209585225822184] Second Eccentricity Squared..........[0.006739728958003832]
Ellipsoid [INTERNATIONAL 1924] Semi-Major Axis (Equatorial Radius)..[6378388.0] Semi-Minor Axis (Polar Radius).......[6356911.946] Flattening...........................[0.003367003387062615] Flattening Inverse...................[296.9999982305938] First Eccentricity...................[0.0819918902228546] First Eccentricity Squared...........[0.006722670062316669] Second Eccentricity..................[0.08226888985364195] Second Eccentricity Squared..........[0.006768170237750658]
Ellipsoid [KRASSOVSKY 1940] Semi-Major Axis (Equatorial Radius)..[6378245.0] Semi-Minor Axis (Polar Radius).......[6356863.019] Flattening...........................[0.0033523298336767685] Flattening Inverse...................[298.30000316622187] First Eccentricity...................[0.0818133335834678] First Eccentricity Squared...........[0.0066934215520398155] Second Eccentricity..................[0.08208852138270177] Second Eccentricity Squared..........[0.0067385253427982685]
Ellipsoid [MODIFIED AIRY] Semi-Major Axis (Equatorial Radius)..[6377340.189] Semi-Minor Axis (Polar Radius).......[6356034.448] Flattening...........................[0.0033408506318589907] Flattening Inverse...................[299.32496546352854] First Eccentricity...................[0.08167337375652854] First Eccentricity Squared...........[0.006670539980773649] Second Eccentricity..................[0.0819471469341423] Second Eccentricity Squared..........[0.006715334890645988]
Ellipsoid [SOUTH AMERICAN 1969] Semi-Major Axis (Equatorial Radius)..[6378160.0] Semi-Minor Axis (Polar Radius).......[6356774.719] Flattening...........................[0.003352891899858333] Flattening Inverse...................[298.249997276158] First Eccentricity...................[0.08182018036905428] First Eccentricity Squared...........[0.006694541915624534] Second Eccentricity..................[0.08209543749645103] Second Eccentricity Squared..........[0.006739660857733726]
Ellipsoid [WGS 72] Semi-Major Axis (Equatorial Radius)..[6378135.0] Semi-Minor Axis (Polar Radius).......[6356750.52] Flattening...........................[0.00335277945669078] Flattening Inverse...................[298.2599997755319] First Eccentricity...................[0.08181881069348491] First Eccentricity Squared...........[0.00669431778329633] Second Eccentricity..................[0.08209405395108844] Second Eccentricity Squared..........[0.006739433694124252]
Ellipsoid [WGS 84] Semi-Major Axis (Equatorial Radius)..[6378137.0] Semi-Minor Axis (Polar Radius).......[6356752.3142] Flattening...........................[0.0033528106718309896] Flattening Inverse...................[298.2572229328697] First Eccentricity...................[0.08181919092890624] First Eccentricity Squared...........[0.006694380004260827] Second Eccentricity..................[0.08209443803685366] Second Eccentricity Squared..........[0.006739496756586903]
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