We can define the triangular function as the convolution of two rectangular functions:

The triangular function is a refinable function.

Triangular function, tri(t)

For example, Klimov and Shamir proposed triangular functions (T-Functions) with a single cycle on n bit words.

Assuming the fundamental diagram (flow-density) is a triangular function, a traffic state A with speed v and density k can be assumed in the congestion region.

As mentioned before, is a triangular function, nonzero over two knot spans rising from zero to one on the first, and falling to zero on the second knot span.