I have a X-Y-Diagram in #Excel, it is a unity circle (not so important) and I need a pointer that I can drag to any point in the diagram, and it should show me the X and Y value and the length of the pointer.
The Pointer should be defined by its starting point, the length should be calibrated to the length from 0 to 1/Xd, and 1/Xd should be the starting point of the pointer which should be fixed. 1/Xd is a point on the X axis, it is always y=0, so it lays on the x axis.

All values needed will be available in a table in Excel.

Anyone any idea how to “program” this?