Or should that end with "oh my!". 😀
So I'm back tinkering my raw data viewer program again...
Thus far I've built an underlying framework that makes this one much much slicker than the old from 2005. In fact, I'd go so far to say to put this new one next to my old I would be embarrassed to admit not only having written the old but actually distributed it to some for actual use.
The memory and executable foot-print is incredibly smaller and execution of load times is simply mind-boggling. Of course a lot credit goes to better hardware and a far more sophisticated development framework than before.
Anyway, I'm getting into formatting (for display purposes) some things like bearings and angles and have long forgotten some stuff and am in need of some reminding.
Zenith angle: That measures from straight over-head pointing toward Earth center?
So the top of my head would 0 degrees and the bottom of feet would be 180?
If that is correct, assume I'm 5' 8" making my zenith distance 5.66667???
Angle right: I have a value in one of my sample files of 307 degrees. If I'm looking straight ahead would that be like looking to the left 53 degrees?
I'm also going to assume all these angle values are decimal degrees. Can someone confirm that please.
As an aside, in the mode setup record (2nd one in the raw file data) it has an option for angle units (AU) which is either degrees(=0) or Gradians(=1) (not radians). Does anyone actually use gradians?
Thanks
E.
Eric,
we in Belgium use the Grads or gons (400 gons make a full circle)
I think most European countries use the gons now. (not for the UK I guess)
Chr.
Zenith Angle of 0° is straight up 90° would be level in face1 (direct) 180° is straight down and 270° would be level in face2 (reverse).
Angles right are measured from zero in a clockwise direction, so yes an angle right of 307° would put you looking to the left of the backsight by 53°.
Angle values in rw5's are in DDD.MMSS format where 45°30'15" would show up as AR45.3015
Gradians were formerly known as Gons where a circle is 0-400 instead of 0-360 with degrees. I would suspect that nations using the metric system likely use Gradians also.
> Zenith angle: That measures from straight over-head pointing toward Earth center?
> So the top of my head would 0 degrees and the bottom of feet would be 180?
In "face left" (normal) mode:
00 => up
90 => horizontal, ahead
180 => down
270 => horizontal, behind
In "face right" mode, the 90 and 270 are swapped.
> If that is correct, assume I'm 5' 8" making my zenith distance 5.66667???
I assume that's a joke.
> Angle right: I have a value in one of my sample files of 307 degrees. If I'm looking straight ahead would that be like looking to the left 53 degrees?
Angle right and Angle left are explementory (ie, sum to 360)
Be care with your description, though. Angles are measured from a backsight, left/right to a foresight.
> I'm also going to assume all these angle values are decimal degrees. Can someone confirm that please.
No, don't assume! I think most instruments record in good old DD.MMSS. But the documents or meta settings should state the exact units.
> As an aside, in the mode setup record (2nd one in the raw file data) it has an option for angle units (AU) which is either degrees(=0) or Gradians(=1) (not radians). Does anyone actually use gradians?
Yes, some european surveyors use gradians (aka gons). 360 deg == 400 gon
THANKS already - distance, angle and bearings, and such
Well... crap.
Seems like I already have some things to [RE] address.
I had never heard of a gon.
If I'm given an AR12.3456 and my job is set to gons, how exactly is displayed in "human" terms?
Easy enough to change my DMS formatter to handle DD.MMSSsss
Having a circle as 400 gon units is fine.
That makes me wonder why the metric folks never went to something like 20, 30 or 40 hour day with 100 minutes per hour and 100 seconds per minute... since we like things evenly divisible by tens.
A "decimal time" if you will. Ironically, that is not at all a new thought to me. About 30 years ago I got tasked to write a search routine with many parameters, times and dates included. Time fields were represented as 12 hour + AM/PM indicators. To make that job easier for my search algorithm I converted all time fields to a decimal time. That made it easy for a simple numeric comparison.
Thanks for help guys.
All inputs are welcome.
E.