XYZ shapefiles from worldwind

[mdsumner]

These look like a good set for testing on:

http://dds.cr.usgs.gov/srtm/version2_1/SWBD/SWBDwest/

found on the Worldwind forum: http://forum.worldwindcentral.com/showthread.php?26821-Sample-3-D-Shapefile

[edzer]

Thanks for the link -- seems to work well:

> library(sf)
Linking to GEOS 3.5.0, GDAL 2.1.0
> s = st_read(".", "w001n05f")
Reading layer w001n05f from data source . using driver "ESRI Shapefile"
features:       16
fields:         1
geometry type:  POLYGON
> plot(s)
> st_geometry(s)
Simple feature collection with 16 features
feature type: POLYGON
dimension:    XYZ
bbox:         xmin: -1.000139 ymin: 4.999861 xmax: 0.0001388889 ymax: 5.992361
epsg (SRID):  NA
proj4string:  NA
precision:    double (default; no precision model)
First 5 geometries:
POLYGONZ((-0.795416666666667 5.99208333333333 1... 
POLYGONZ((-0.0359722222222221 5.73763888888889 ... 
POLYGONZ((-0.0706944444444444 5.72402777777778 ... 
POLYGONZ((-0.102916666666667 5.68652777777778 1... 
POLYGONZ((-0.0373611111111111 5.63013888888889 ... 

[cjtexas]

I'm finding if one reads in a file that has an empty Z dimension, this error is produced Error in .local(obj, ...) : NA values in coordinates and so far, I haven't found a native (sf) way to drop the Z dimension...

[cjtexas]

I should clarify, I only receive that error when trying to coerce back to sp classes using as(test_sf, "Spatial")

I also tried this... test_asSPDF <- as(na.omit(test_sf), "Spatial") Error in .local(obj, ...) : NA values in coordinates

And, for what it's worth: all(sf::st_is_valid(test_sf)) returns TRUE all(sf::st_is_simple(test_sf)) returns TRUE

[edzer]

try st_dropzm, now added.

[cjtexas]

Thanks @edzer, will give it a try!