Recurrence plot
In descriptive statistics and chaos theory, a recurrence plot (RP) is a plot showing, for each moment j {\displaystyle j} in time, the times at which the state of a dynamical system returns to the previous state at i {\displaystyle i} , i.e., when the phase space trajectory visits roughly the same area in the phase space as at time j {\displaystyle j} . In other words, it is a plot of x → ( i ) ≈ x → ( j ) , {\displaystyle {\vec {x}}(i)\approx {\vec {x}}(j),} showing i {\displaystyle i} on a horizontal axis and j {\displaystyle j} on a vertical axis, where x → {\displaystyle {\vec {x}}} is the state of the system (or its phase space trajectory).