(HP-65) Horizontal Sextant angles to Rectangular Coordinates

[PedroLeiva]

(05-21-2019 12:09 PM)SlideRule Wrote:  An extract from A New Station Pointer - The Hewlett-Packard HP 65, Commander J.B. Dixon (R.N.), International Hydrographic Review, July 1976

Very interesting because it can easily adapt to other HP, such as HP-67. What a pity it does not include numerical examples to test the program. It looks like Resection, "The Three Point Problem" (Pothenot)

If it is, here a numeric example:

I-Data:
a) Coordinates
95,7455 *** Ax
75,3647 *** Ay

100,0000 *** Bx
100,0000 *** By

99,3922 *** Cx
144,9959 *** Cy

b) Angles view [dd.mm.ss]
33,2010 *** alpha (=left)
47,3530 *** beta (right)

II- Solution:
a) Lateral angles [dd.mm.ss]
66,2744 *** A
43,1056 *** C
Central angle
169,2540 *** B
b) Coordinates of Position (P)
58,2933 *** Px
100,0000 *** Py

c) Lenghts
c1) Distance between points
25,0000 *** AB
45,0000 *** BC
c2) Lenght from points to position
44,8282 *** AP
41,7067 *** BP
60,9406 *** CP

This was solved by Resection program from HP-67 Survey PAC I
Pedro