How Can I Use navX mxp to Rotate a Tank Drive?

In the navX sample code they used mecanum drive. But how can I rotate using a Tank Drive? In the PIDController it gives an output that is used in the mecanum drive. I was wondering if there is a way to somehow convert the output into the two different speeds to feed into the left and right motors to turn, and how can I do the math? Or is there a better way to do this?

Our drivetrain code should answer your question

Set one side to the output value, and the other side to negative output value