tri-axial accelerometer data and matlab statistics

I currently have some tri-axial accelerometer data (Accx,Acc,Accz)basically giving me posture and motion information. Does any know of an algorithm or a way to analyze this data so I can get statistically data such as wake time, number of awakenings, sleep latency or any sleep statistics as well as day time statistics from this accelerometer data. The statistics should look similar to the data you get from an actigraphy watch.