[R-sig-Geo] st_write and gpx file

[Patrick Giraudoux]

I have made some additionnal trials, with the argument 'driver' 
explicit. It appears that the sf object 'walk' must compulsory have two 
fields names "track_fid" and "track_seg_id" respectively. Once created :

> walk  Simple feature collection with 2095 features and 3 fields Geometry 
type: POINT Dimension: XY Bounding box: xmin: 5.951268 ymin: 47.29238 
xmax: 5.974512 ymax: 47.3015 Geodetic CRS: WGS 84 First 10 features: 
track_fid ele geometry track_seg_id 1 1 243 POINT (5.95348 47.29709) 1 2 
1 243 POINT (5.953438 47.29704) 1 3 1 244 POINT (5.953219 47.29702) 1 4 
1 243 POINT (5.952884 47.29713) 1 5 1 243 POINT (5.952492 47.2972) 1 6 1 
243 POINT (5.952335 47.29743) 1 7 1 242 POINT (5.951881 47.29732) 1 8 1 
242 POINT (5.951495 47.29724) 1 9 1 293 POINT (5.951333 47.29719) 1 10 1 
294 POINT (5.951388 47.29706) 1


Then,

st_write(walk,dsn="walk.gpx",layer="track_points",driver="GPX")

is written with no error

However, st_write(walk,dsn="walk.gpx",layer="track_points") still gets 
'Error: Could not guess driver for walk.gpx'




Le 05/03/2022 à 20:24, Ahmadou Dicko a écrit :
> Hi Patrick,
>
> You can add the driver manually.
>
> st_write(walk, dsn = "walk.gpx", layer = "track_points", driver = "GPX")
>
> Hope it helps,
> Ahmadou
>
>
> On Sat, Mar 5, 2022 at 6:53 PM Patrick Giraudoux 
> <patrick.giraudoux using univ-fcomte.fr> wrote:
>
>     Dear listers,
>
>     I am making trials with the sf package trying to write point
>     geometries
>     into afile. Here is the sf object:
>
>     > walk  Simple feature collection with 2095 features and 2 fields
>     Geometry
>     type: POINT Dimension: XY Bounding box: xmin: 5.951268 ymin: 47.29238
>     xmax: 5.974512 ymax: 47.3015 Geodetic CRS: WGS 84 First 10 features:
>     track_seg_point_id ele geometry 1 0 243 POINT (5.95348 47.29709) 2
>     1 243
>     POINT (5.953438 47.29704) 3 2 244 POINT (5.953219 47.29702) 4 3 243
>     POINT (5.952884 47.29713) 5 4 243 POINT (5.952492 47.2972) 6 5 243
>     POINT
>     (5.952335 47.29743) 7 6 242 POINT (5.951881 47.29732) 8 7 242 POINT
>     (5.951495 47.29724) 9 8 293 POINT (5.951333 47.29719) 10 9 294 POINT
>     (5.951388 47.29706)
>
>     Writing a shapefile as well as a kml is no problem:
>
>     st_write(walk,"walk.shp")
>
>     st_write(walk,"walk.kml")
>
>     But I cannot go through writing a gpx file, e.g.
>
>     > st_write(walk,dsn="walk.gpx",layer="track_points") Error: Could
>     not guess driver for walk.gpx
>
>     I have tried several other combinations all unsuccessful.
>
>     Have someone an idea about what goes wrong ?
>
>     Best,
>
>     Patrick
>
>
>
>
>
>             [[alternative HTML version deleted]]
>
>     _______________________________________________
>     R-sig-Geo mailing list
>     R-sig-Geo using r-project.org
>     https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>
>
>
> -- 
> Ahmadou H. DICKO, PhD
>
> Statistical consultant
> Mobile: (+221) 77 123 81 69
> Skype: dicko.ahmadou.h
> Twitter : @dickoah
> Gitlab: gitlab/dickoa
> Github: github/dickoa


	[[alternative HTML version deleted]]