Description Usage Arguments Value Note Examples
Disperse flows throughout a network based on a input vectors of origin points and associated densities
1 2 3 4 5 6 7 8 9 10  dodgr_flows_disperse(
graph,
from,
dens,
k = 500,
contract = FALSE,
heap = "BHeap",
tol = 0.000000000001,
quiet = TRUE
)

graph 

from 
Vector or matrix of points from which aggregate dispersed flows are to be calculated (see Details) 
dens 
Vectors of densities corresponding to the 
k 
Width coefficient of exponential diffusion function defined as

contract 
If 
heap 
Type of heap to use in priority queue. Options include
Fibonacci Heap (default; 
tol 
Relative tolerance below which dispersal is considered to have
finished. This parameter can generally be ignored; if in doubt, its effect
can be removed by setting 
quiet 
If 
Modified version of graph with additional flow
column added.
Spatial Interaction models are often fitted through trialling a range of values of 'k'. The specification above allows fitting multiple values of 'k' to be done with a single call, in a way that is far more efficient than making multiple calls. A matrix of 'k' values may be entered, with each column holding a different vector of values, one for each 'from' point. For a matrix of 'k' values having 'n' columns, the return object will be a modified version in the input 'graph', with an additional 'n' columns, named 'flow1', 'flow2', ... up to 'n'. These columns must be subsequently matched by the user back on to the corresponding columns of the matrix of 'k' values.
1 2 3 4 5 6 7 8  graph < weight_streetnet (hampi)
from < sample (graph$from_id, size = 10)
dens < rep (1, length (from)) # Uniform densities
graph < dodgr_flows_disperse (graph, from = from, dens = dens)
# graph then has an additonal 'flows` column of aggregate flows along all
# edges. These flows are directed, and can be aggregated to equivalent
# undirected flows on an equivalent undirected graph with:
graph_undir < merge_directed_graph (graph)

Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.