Suitability

[marcusyoung]

Hi,

I'm thinking of using pgMapMatch for some work I'm doing on data from a walking/cycling mapping application. The data we have been provided with does not have any timestamps. I am thinking that if a fixed speed is assumed (e.g. 3mph for walking) I can generate pseudo timestamps based on the distance between vertices. Is there any reason that might not work?

I'm just as interested in traces that do not correspond with a road or path. However, there may be correspondence for part of the trace and not another part(s). How does pgMapMatch handle that scenario?

Thanks

Marcus

[amillb]

Yes, you could use pseudo timestamps. However, in that case, there isn't much advantage to using pgMapMatch, and it is likely to be slower that alternatives (e.g. grasshopper). The key advantage of pgMapMatch is that is assesses the likelihood of a particular path based on the speed.

I don't know of any map matching tool that will allow for paths that are not on a road or path. You could look for traces that have a low match score, and adjust those manually, depending on how many you have.

[marcusyoung]

I was mainly looking at pgMapMatch as it is postgreSQL/Postgis/pgRouting based, which fits well with all the other aspects of the project.