Issue with viaroute example about stplanr

[richardellison]

I'll have a look, the error implies that the number of routes doesn't match the summary information which seems rather odd (and I'm sure this example worked when I tried it a few weeks ago).

[Robinlovelace]

Thanks for the fix - no longer errors but I get some strange warnings and the output looks strange:

> exroutes <- viaroute(viapoints=list(data.frame(x=c(-33.5,-33.6,-33.7),y=c(150,150.1,150.2))))
> r <- viaroute2sldf(exroutes)
Warning messages:
1: In bind_rows_(x, .id) : Unequal factor levels: coercing to character
2: In bind_rows_(x, .id) : Unequal factor levels: coercing to character
3: In bind_rows_(x, .id) : Unequal factor levels: coercing to character
4: In bind_rows_(x, .id) : Unequal factor levels: coercing to character
plot(r)

[Robinlovelace]

Compared with this from the osrm package:

install.packages("osrm")
library(osrm)
r_osrm <- osrmTrip(data.frame(i = 1:3,x=c(150,150.1,150.2),y=c(-33.5,-33.6,-33.7)))
plot(r_osrm[[1]]$trip)

[Robinlovelace]

Also this seems to generate an error with the stplanr implementation:

origin = tmap::geocode_OSM("London")
destination = tmap::geocode_OSM("Leeds")
od_df = rbind(origin$coords, destination$coords)
exroutes <- viaroute(viapoints = list(od_df))
r <- viaroute2sldf(exroutes)

Error in data.frame(routenum = i, legnum = j, routedesc = rep(x$routes$legs[[i]]$summary[j],  : 
  arguments imply differing number of rows: 1, 2, 0

Interestingly this also seems to fail with osrm:

ro = osrmRoute(origin, destination)

osrmRoute function returns an error: 
Error: URL string malformed close to position 31: "73, 51"

[Robinlovelace]

Update: it works with osrm: riatelab/osrm#17

[richardellison]

Reopening, seeing the same thing. I'll have another look.

[Robinlovelace]

Any update on this @richardellison? Thinking better to fix bugs before adding new features and improving performance.

[richardellison]

This has been fixed in #161. The following now returns the correct geometries.

exroutes <- viaroute(viapoints=list(data.frame(x=c(-33.5,-33.6,-33.7),y=c(150,150.1,150.2))))
r <- viaroute2sldf(exroutes)

You will notice that this is different from the result returned by the osrm package. This is because the "osrm" package calculates the individual routes between each pair of coordinates while this implementation uses the coordinates as waypoints on a single route. To return the same result as the "osrm" package you can run the following:

exroutes2 <- viaroute(viapoints=list(
    data.frame(x=c(-33.5,-33.7),y=c(150,150.2)),
    data.frame(x=c(-33.6,-33.7),y=c(150.1,150.2))
))
r2 <- viaroute2sldf(exroutes2)