global Pi
Pi =3.1415926535

print "Mean Angle( "; chr$( 34); "350,10"; chr$( 34); ") = ";         using( "###.#", meanAngle( "350,10")); " degrees."             '          0
print "Mean Angle( "; chr$( 34); "90,180,270,360"; chr$( 34); ") = "; using( "###.#", meanAngle( "90,180,270,360")); " degrees."  '        -90
print "Mean Angle( "; chr$( 34); "10,20,30"; chr$( 34); ") = ";       using( "###.#", meanAngle( "10,20,30")); " degrees."        '         20

end

function meanAngle( angles$)
   term =1
   while word$( angles$, term, ",") <>""
      angle  =val( word$( angles$, term, ","))
      sumSin = sumSin +sin( degRad( angle))
      sumCos = sumCos +cos( degRad( angle))
      term =term +1
   wend
   meanAngle= radDeg( atan2( sumSin, sumCos))
   if abs( sumSin) +abs( sumCos) <0.001 then notice "Not Available." +_
     chr$( 13) +"(" +angles$ +")" +_
     chr$( 13) +"Result nearly equals zero vector." +_
     chr$( 13) +"Displaying '666'.": meanAngle =666

end function

function degRad( theta)
    degRad =theta *Pi /180
end function

function radDeg( theta)
    radDeg =theta *180 /Pi
end function

function atan2( y, x)
    if x >0           then at =atn( y /x)
    if y >=0 and x <0 then at =atn( y /x) +pi
    if y <0  and x <0 then at =atn( y /x) -pi
    if y >0  and x =0 then at =    pi /2
    if y <0  and x =0 then at = 0 -pi /2
    if y =0  and x =0 then notice "undefined": end
    atan2 =at
end function