I have a Yamaha PGP model. On this piano, I can select a "style" of music (Christmas swing, Latino, rock, etc.). I then hit the "ACMP" and "Start/Stop" buttons and the piano will create an accompaniment based on the chord I play with my left hand. I can also enable a "harmony" setting and the piano will then generate a harmony to go along with the melody I play with my right hand. Is there anything like this in GarageBand?