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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. *

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

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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"

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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. *

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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

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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. *

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RCL should make ENTER^ superfluous.

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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.

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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. *