Mazak Mazatrol Smooth G Programming and Milling Hex
App that I use is called CNC Machnist pro from Google play store, it has a Geometry Calculator where you enter the size of Hex, Square, areas of circle and bunch of other goodies, and that calculator provides a dimension across the lines, to radius perimeter of the square, and I divide this in half and my number comes up that I input into r/x.