#### MAPepin

##### New Member
I'm in a bit of a jam. I'm trying to figure out an Excel spreadsheet problem using RADIANS and DEGREES and just can't seem to figure it out. This has to do with ship (maritime) navigation.

Here's the problem:
I want to input any given course within the 360° of a circle and output the possible courses to steer if I came left or right 15°, 30°, 45°, 60°, 75°, or 90°.

So, if I were to use a course of 000° as my base input, it would look something like this:
---------------------------------------
BASE COURSE: 000°

LEFT diff RIGHT
345° 15 015°
330° 30 030°
315° 45 045°
300° 60 060°
285° 75 075°
270° 90 090°
---------------------------------------

If I were to change the base course input, all numbers would instantly update:

---------------------------------------
BASE COURSE: 120°

LEFT diff RIGHT
105° 15 135°
090° 30 150°
075° 45 165°
060° 60 180°
045° 75 195°
030° 90 210°
---------------------------------------

One big thing that I need with this is to be able to subtract numbers to the left while treating 000° the same as 360° so that if I subtract (come left) 45° from the course 030° I get 345° and not -15.

Is this even possible in Excel without any VB programming? Am I using the wrong functions?

Mike

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Name Manager, New Name. Yesterday =TODAY()-1. OK. Then, use =YESTERDAY in any cell. Tomorrow could be =TODAY()+1.

#### tusharm

##### MrExcel MVP
Lightly tested...

For left use =MOD(360+\$D\$2-\$C5,360) where D2 is the base heading and C5 is the degrees to turn.

For right use =MOD(360+\$D\$2+\$C5,360)

#### MAPepin

##### New Member
AWSOME ...

I put it through the wringer in testing it out and it worked like a champ !!!

WOOT!! A toast to you.