# stomped...converting bearings to angles

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# stomped...converting bearings to angles

Hello,

I can usually find a solution to what I am trying to do in excel but I am stomped on this one.

I have hundreds of entries that I need to convert from surveyor bearings (like N 37°42'17" W) to absolute decimal  angle . I have the mathematical conversion down path but I am stomped on how to automate the calculations.
The sample bearing here is North by West meaning aiming North (0/360) and rotating towards the West (counter clockwise) so in this case the result should be 360 - the angle. If it were North by East then it should be 0 + the angle.
Using as a reference North as 0/360 with a clockwise direction there are 4 possibilities.
N by W (360 -angle)
N by E (0+ angle)
S by W (180 + angle)

S by E (180 - angle)

Here are a few sample entries

 degrees minutes seconds decimal angle S 28 25 37 W 28.42694 208.4269 S 82 12 42 E 82.21167 97.78833 N 45 0 0 E 45 45

As it is now I enter manually each formula to calculate the resulting angle.
I would like for the angle to calculate on its own based on the N-S-E-W directions.

Any suggestion on how to do this?