The derivative of the objective function with respect to 
(12), used to compute the optimal step length 
, is
With the above preliminaries, we can now outline the implementation of the EMME/2 equilibrium transit assignment macro CONGTRAS (CONGested TRansit ASsignment):
US1 to 0.
2.41
2
Compute total number of transit trips and initialize iteration counter 
.
3.21
3
Perform uncongested fixed cost assignment to obtain 
and 
.
5.11/5.31
4
Compute congestion cost .
2.41
5
Increment iteration counter 
.
3.21
6
Compute new segment congestion costs 
