tReach: computes sizes of temporally reachable sets in a dynamicNetwork

Description

computes sizes of temporally reachable sets in a dynamicNetwork, using either a full census or sample of starting vertices of the specified size

Usage

tReach(nd, direction = c("fwd","bkwd"), sample=network.size(nd),
      start, end,  graph.step.time=0)

Arguments

a networkDynamic object

direction

currently only 'fwd' works, to calculate the sizes forward-reachable sets (as opposed to backwards-reachable)

sample

numeric, indicates the size of the sample of vertices to use to calculate the reachable sets

start

optional numeric start time to begin path search

end

optional numeric time to end path search

graph.step.time

How much time should be added for each edge traversal (graph hop)? See tPath for details.

Value

a vector of length equal to sample giving the sizes of the set of vertices reachable from each seed vertex within the specified time bounds

Details

tReach calls link{tPath} on with each starting vertex to determine the sizes of the sets of vertices that are reachable. If sample is set to something less than the size of the network, it will sample that many vertices instead of doing the (expensive) full census. Note that when the vertices are chosen as a sample, results may vary between calls to this function

Examples

Run this code

# NOT RUN {
data(moodyContactSim)
tReach(moodyContactSim)

# only sample 3 paths
tReach(moodyContactSim,sample=3)

# what fraction of the network could each vertex reach?
tReach(moodyContactSim)/network.size(moodyContactSim)

# what fraction of the network could each vertex be reached by?
tReach(moodyContactSim,direction='bkwd')/network.size(moodyContactSim)
# }