HP49-50G : —>g gravity calculation = g(latitude, height) with WGS84

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HP49-50G : —>g gravity calculation = g(latitude, height) with WGS84 - Gil - 09-25-2021 08:27 AM

HP49-50G
Gravity g calculation in function of two arguments:
- latitude (in d.mmss), in stack level 2
- height/altitude (in m), in last stack level 1,

According to equations & parameters:
- International gravity 1967
- WGS 84.

See, for example, for more details:
https://en.m.wikipedia.org/wiki/Theoretical_gravity

The code is:

\<< "Version 2b 2021.09.25

2 Arg
. lat [in D.mmss]
. alt [in m]

https://en.m.wikipedia.org/wiki/Theoretical_gravity
https://eu.docworkspace.com/d/sIEG9949c5qq2igY
(GSR 80 by H Moritz)

\[]g(90,0)=9.8321849378
but form\->9.83218493787
\[]\GD calc poss. for alt
" DROP "alt [m]" \->TAG SWAP "lat D.mmss" \->TAG DUP2 RCLF \-> alt lat f
\<< DEG lat HMS\-> 'lat' STO DEG '9.780327*(1+.0053024*SIN(lat)^2-.0000058*SIN(lat*2)^2)-.000003086*alt' \->NUM "Lambert GRS 80" \->TAG '9.7803267715*(1+.0052790414*SIN(lat)^2+.0000232718*SIN(lat)^4+.0000001262*SIN(l​at)^6+.0000000007*SIN(lat)^8)-(1-.00139*SIN(lat)^2)*.0000030877*alt+7.2E-13*alt^2' \->NUM "Somigliana GRS 80" \->TAG '9.7803253359*((1+1.9318526464E-3*SIN(lat)^2)/\v/(1-6.69437999014E-3*SIN(lat)^2))-(1-.00139*SIN(lat)^2)*.0000030877*alt+7.2E-13*alt^2' \->NUM "Somigliana WGS 84" \->TAG f STOF
\>>
\>>


RE: HP49-50G:Theorical Earth gravity g = g(latitude, height), WGS84, GRS80/67 - Gil - 11-15-2021 09:42 AM

Version 17e

Here was unified the use of gravities guFR and gbetaFR with the ending FR (like FREE ellipsoid), instead of sometimes only gu and gbeta.

So that gMAGNIT is now correctly calculated.


RE: (49g 50g) Theoretical Earth gravity g = g(latitude, height), WGS84, GRS80/67 - Gil - 2025-02-01 07:11 AM

Version 19

As before. Just used, for increased accurateness, the built-in D->R and R—>D functions of the HP50G (instead of the manual conversion by 180/pi).