Plotting X, Y Values with Cartesian Coordinates with 0° on Top and Angles measured CW

Dear All:

I want to Plot a Point with x, y coordinates on a Chart and call it Moon. This Chart has to be similar to a map with the North on the top. As with maps and the Compass directions on a map, 000° starts from top and angles are measured Clockwise. Diagram Attached.

Moon_New.JPG

I could use a unit such a 5 and get the x, y coordinates as the Sine and the Cosine values of the Angle from top. My problem is 0° start on the +ve X-Axis in Excel Charts and angles are measured Counter-Clockwise as is Geometry. Any solutions?

See if anything I have to say here helps at all: https://www.excelforum.com/tips-and-...ml#post4309792

Thank you very much... I think I will find the answer there... Will revert after I read them properly...

Yes I did go through your quite complex worksheets.

Could you please give me a very simple formula for X and Y values to plot a Point (Moon) on a 'Compass based chart' say with an 'r' = 5 units on a Compass Bearing of 045° Degrees? (Values for all my 'points' are in Degrees). Thanks.

How do you usually convert between polar and Cartesian coordinates?

The points I would hope you would see is:

1) Under the standard convention, x=r*cos(angle) and y=r*sin(angle) where angle is measured CCW from the positive horizontal (x) axis.
2) Under the "compass bearing" convention, x=r*sin(angle) and y=r*cos(angle) where angle is measured CW from the positive vertical (y) axis.

In your case, r is 5 and angle is 45 degrees (remember that you must convert to radians to use Excel's trig functions). x=5*sin(45 degrees converted to radians) and y=5*cos(45 degrees converted to radians). Unless there is something missing, it should be that simple.

You might review this tutorial about converting from polar to cartesian coordinates (and vice versa) https://www.mathsisfun.com/polar-car...ordinates.html

Thank you very much. I played around with your worksheet 'unitcircle_compassbearing.xlsx' and got the hang of it. Exactly what I wanted!

I will be marking your answer as [Solved] and will +1 to Reputation.

Thanks once again...