I have some data samples, they are some traffic accident locations (have shape files) I really want to use the dijkstra function of pgrouting to look into their shortest distances between each other. However, I noticed that dijkstra requires all the points need to be the vertices of a topology. But obviously my data points are not the vertices of the road network. Is there any way to integrate my data points to the road network and make them vertices too? What is the good approach to route non-vertex data like this? Thank you.

I have some data samples, they are some traffic accident locations (have shape files) I really want to use the dijkstra function of pgrouting to look into their shortest distances between each other. However, I noticed that dijkstra requires all the points need to be the vertices of a topology. But obviously my data points are not the vertices of the road network. 

Is there any way to integrate my data points to the road network and make them vertices too? 

What is the good approach to route non-vertex data like this?

I noticed that in pgrouting's Dijkstra function, one has to provide a starting point, but it requires the starting point must be a vertex. How can I start from an arbitrary point(such as an arbitrary pair of gps coordinates). Thank u.

I have some data samples, they are some traffic accident locations (have shape files) I really want to use the dijkstra function of pgrouting to look into their shortest distances between each other. However, I noticed that dijkstra requires all the points need to be the vertices of a topology. But obviously my data points are not the vertices of the road network. Is there any way to integrate my data points to the road network and make them vertices too? What is the good approach to route non-vertex data like this? Thank you.