Alluvial flow diagram

Four video gamers play computer games during the morning, afternoon, and evening.
A matrix shows how many hours each gamer played during each part of the day.
Use an alluvial flow chart to graphically study the parts of the day when gamers like to play, and how the gamers distribute their play time.
The function was tested using R2008a. A comment showcases how automatic scalar and vector expansions (introduced in R2016b) can greatly simplify expressions.