Long description

This figure is a graph of x[n] against n. The vertical axis shows eight evenly spaced levels consisting of three-bit binary numbers ranging from 000 to 111, and horizontal lines are drawn across the graph to indicate these levels. A graph line representing the signal is shown fluctuating up and down. A series of evenly spaced vertical lines, representing the samples, extend from the horizontal axis to the horizontal level line to which the signal is nearest at that time. Each vertical line has a small filled circle at the point where the vertical line meets the horizontal level line.