Direction to Rotation

Vector3 DirToRot(Vector3 Dir)
        {
            try
            {
                /*
                This is rotation to direction:
                rotx = 0.2
                retx = 0.2 *  0.0174532924 = 0.00349065848 //radians to degrees
                Cos(0.2 *  0.0174532924) = 0.9999939076578741
                absx = Abs(Cos(0.2 *  0.0174532924)) = 0.9999939076578741

                rotz = 0.3
                retz = 0.3 * 0.0174532924 = 0.00523598772 //radians to degrees

                dirx = -Sin(retz) * absx =  -0.005235963795437085 * 0.9999939076578741 = -0.0052359318961542843713968514009985 //-0.0052359318961542846 if rounded
                diry = Cos(retz) * absx = 0.9999862922476151 * 0.9999939076578741 = 0.999980199989
                dirz = Sin(retx) = 0.0052359637954370846088922220789420743196847079456760

                now this is direction to rotation:
                dirz = Sin(retx) =  0.0052359637954370846088922220789420743196847079456760
                num1 = retx = Asin(dirz)
                rotx = num1 / 0.0174532924

                num2 = absx = Abs(Cos(num1)
                num3 = diry / num2 = Cos(retz)
                num4 = retz = Acos(num3)
                rotz = num4 / 0.0174532924

                roty?


                */
                float dirz = Dir.Z;
                float num1 = (float)Math.Asin(dirz);
                float rotx = num1 / 0.0174532924f;

                float dirx = Dir.X;
                float num2 = (float)Math.Cos(num1);
                float num3 = dirx / num2;
                float num4 = (float)Math.Asin(-num3);
                float rotz1 = num4 / 0.0174532924f;

                float diry = Dir.Y;
                float num5 = (float)Math.Cos(num1);
                float num6 = diry / num5;
                float num7 = (float)Math.Acos(num6);
                float rotz2 = num7 / 0.0174532924f;

                if (rotz1 > 0)
                {
                    if (rotz2 < 90)
                    {
                        trueRotZ = rotz1; //trueRotZ is a global float variable.
                    }
                    else
                    {
                        trueRotZ = rotz2;
                    }
                }
                else
                {
                    if (rotz2 < 90)
                    {
                        trueRotZ = rotz1;
                    }
                    else
                    {
                        trueRotZ = -rotz2;
                    }
                }

                return new Vector3(rotx, 0, trueRotZ);
            }
            catch
            {
                return Vector3.Zero;
            }
        }