on mouseUp
    ask "Enter lng,lat,meridian"
    if it is empty then exit mouseup
    // -150.5, -4.95, -150.0
    put item 1 of it into longitude
    put item 2 of it into latitude
    put item 3 of it into meridian

    repeat with hour = 6 TO 18
        put 15 *hour - longitude + meridian - 180 into hra
        put rad2deg(atan(sin(deg2rad(latitude)) * tan(deg2rad(hra)))) into hla
        if abs(hra) > 90 then put hla + 180 * sgn(hra *latitude) into hla
        put hour && hra && hla & cr after sunhours
    end repeat
    put sunhours
end mouseUp

function rad2deg theta
    return theta * (180 / pi)
end rad2deg

function deg2rad theta
    return theta * (pi / 180)
end deg2rad

function sgn x
    if x >0 then return 1 else return -1
end sgn