This processor computes the fundamental diagram by computing an (average) flow, density and velocity over a certain time (deltaTime). This is done by counting the number of pedestrians crossing a line for some deltaTime. If P is the set of pedestrians crossing in that duration (deltaTime) the flow is defined by: the size of P divided by (te - ts) where ts is the time the first pedestrian crossed the line and te is the time the last pedestrian crossed the line i.e. (te - ts) is smaller or equals deltaTime. The velocity of a pedestrian crossing the line is its velocity the time-step time in which the crossing happens. So it is not exactly the crossing time (plus, minis simTimeStep). The density is defined by: flow divided by (velocity times the length of the crossing line). Therefore, the crossing line has to be defined appropriately. In addition the processor writes out deltaTime, and the measurementTime. The first measurementTime is equal to deltaTime divided by 2, the second is deltaTime plus deltaTime divided by 2 and so on.
For more details see zhang-2011 (doi:10.1088/1742-5468/2011/06/P06004) Method A.
@author Benedikt Zoennchen---
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