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Hello all,

In that the HP-21 (Woodstock) and HP-35 (Classic) do not have conversions to and from degrees to degrees/minutes/seconds, has anyone devised a method to convert the decimal degree value to degrees-minutes-seconds? Please let me know.

Thanks

Edited: 28 Mar 2012, 8:50 p.m.

Not anything automatic. You can obviously do it by working through the calculations manually.

From Hewlett-Packard's HP-35 MATH PAC, available in the HP Museum DVD 1, Calculator Manuals:

Degrees, minutes and seconds to decimal degrees

LINE DATA OPERATIONS DISPLAY REMARKS
1 Seconds ENTER^ 6 0 STO /
2 Minutes + RCL /
3 Degrees +

Example

32.6 ENTER^ 6 0 STO / .5433333333
17 + RCL / .2923888888
46 + 46.29238889 46°17'32.6" = 46.29°


Decimal degrees to degrees, minutes and seconds

LINE DATA OPERATIONS DISPLAY REMARKS
1 X ENTER^ Let D = integer part of X
2 D Degrees
3 - 6 0 STO * A Let M = integer part of A
4 M Minutes
5 - RCL * B Let S = nearest integer to B
6 S Seconds


Example

23.32916667 ENTER^ 23.32916667
23 23. Degrees (integer part of X)
- 6 0 STO * 19.7500002
19 19. Minutes (integer part of X)
- RCL * 45.000012
45 45 Seconds (nearest integer to X)
23.32916667° = 23°19'45"

Quote:
LINE	DATA	OPERATIONS		DISPLAY		REMARKS
1 Seconds ENTER^ 6 0 STO /
2 Minutes + RCL /
3 Degrees +

Interesting, using the single storage register and saving no keystrokes in doing so....

Likewise for the reverse conversion.

- Pauli

Edited: 28 Mar 2012, 10:54 p.m.

There was a tread not too long ago where somebody posted equations that accomplish this. He made his posting as a guessing game, something about "Try to identify these" or something like that. I did a quick search, but came up empty handed. Does this ring any bells?

Very respectfully,

David

Here it is:

Do you know these 2 functions ?

Regards,

Gerson.

Quote:
Interesting, using the single storage register and saving no keystrokes in doing so....

...unless more than one conversion is performed, but then the instructions should be updated:

LINE	DATA	OPERATIONS		DISPLAY		REMARKS
1 Seconds ENTER^ 6 0 STO / for the second and subsequent conversions
execute the following operations instead:
ENTER^ RCL /
2 Minutes + RCL /
3 Degrees +

Gerson.

Edited: 29 Mar 2012, 7:52 a.m.

RCL should make ENTER^ superfluous.

Hello all. Fantastic job on the D.MS<-->D.DDD conversion routines. I tried developing some algorithms last night. In comparison, yours were quite streamlined.

Right you are! This means more keystroke saving on multiple conversions. I guess surveyors appreciated the successor of the HP-35, the HP-45, when it was released.
Still not programmable, but it had ->D.MS and D.MS-> built-in :-)

Also, a nice feature: no matter the current display mode, ->D.MS would leave the calculator temporarily in FIX 4 mode.


Edited: 29 Mar 2012, 2:12 p.m.