I am attempting to convert, to a 360 degree basis, the normal bearings in a survey. The following are the original survey bearings (2nd column) and on the right (4th column) is the 360 basis amount I obtain, which will be entered in Copan map checking. The 3rd column is my interpretation of what I think the survey bearing should be.

1 2 S 05°52'13" E S 05°52'13" E 174.0147 3 N 84°41'49" E S 84°41'49" W 264.4149 4 N 07°36'50" W N 07°36'50" W 352.2310 5 S 50°17'08" E N 50°17'08" W 309.4242 6 N 37°13'00" E N 37°13'00" E 37.13 7 N 52°47'00" W S 52°47'00" E 127.1300 1 S 83°07'18" W N 83°07'18" E 83.0718

The survey plat, with original bearings, is shown under my previous question regarding Map Check file format.

  • Please note: Nobody here is interpreting your survey plat or any of the values on it. We are only addressing procedural/conceptual issues you raise. To properly interpret your plat -- and even state if you have the right plat -- you need to consult a local, professional surveyor. – Martin F Jun 2 '14 at 4:22

The '360 degree basis' is known as azimuth, or clockwise/east degrees from north. The 'normal bearings' are known as quadrant bearings or degrees east/west of north/south. This page I found on a quick search graphically depicts the two.

Survey bearings are given in a direction, but the line can be read in two directions by reversing both cardinals. The key in working a traverse is that you must start at one point and wind up back at that same point, and on a plat like your image lines aren't labeled both ways. You must pick a point and then flip the bearing as needed to work your way around. It appears you understand this.

To answer your title question, the Copan software you are using has a program setting where you can switch expected input between the two. It is referenced on the bearing expression page of the user manual. You can manually convert if you like (checking your math above in part requires checking your bearing directions and we would need to know the parcel you are specifically looking at an your point of beginning), but I would recommend changing the program setting so you can just input the data in the format you have.

Actually, according to the program setting page it looks like you can use either form for input regardless of the setting. If I've got the syntax from the expression page right, your call 2 above would be S 5.5213 E - no need to convert to azimuth to input it.

  • You're correct: Copan will allow either format for input, and will output according to the format choice in Program Settings. – Martin F Jun 2 '14 at 3:56

Manually converting bearings can be error-prone, as exemplified by some of your conversions, above:

Bearing S 05° 52' 13" E converts to azimuth 174° 07' 47" and not 174° 01' 47". Also, bearing N 50°17'08" W converts to azimuth 309° 42' 52" and not 309° 42' 42".

However, as Chris says, you can enter quadrant-based bearings in Copan without having to manually convert them to whole-circle bearings:

If a survey bearing is normally written as N 84° 41' 49" E it can be entered into Copan as n84.4149e. Likewise N 52° 47' 00" W can be entered as n52.47w.

Note, however, that quadrant-bearings, when labelled on survey plats, are often only in the form N angle E or N angle W and are thus bi-directional.

And, as you have noticed, that if you are entering bearings into a Copan Map Traverse or Map Check, you must traverse in one consistent direction all the way along/around the traverse. This can be clockwise or counter-clockwise, as you're consistent for any particular traverse. Thus, you must occasionally "flip" an originally written bearing by 180° to mean the opposite orientation. Luckily, quadrant-based bearings are very easy to "flip".

To flip N 84° 41' 49" E just change the cardinals S 84° 41' 49" W and enter in Copan s84.4149w And N 52° 47' 00" W flipped is S 52° 47' 00" E and enter s52.47e.

If you look in Copan Map Traverses (which is just like Map Check but allows you to adjust traverses and save points), there are some examples of quadrant-bearing traverses.

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