[ https://issues.apache.org/jira/browse/ARROW-10386?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Neal Richardson reassigned ARROW-10386: --------------------------------------- Assignee: Romain Francois > [R] Spatial (sf geometry) data does not roundtrip correctly (attributes lost) > ----------------------------------------------------------------------------- > > Key: ARROW-10386 > URL: https://issues.apache.org/jira/browse/ARROW-10386 > Project: Apache Arrow > Issue Type: Bug > Components: R > Affects Versions: 2.0.0 > Environment: Mac OS 10.15.7 > R 4.0.2 > arrow 2.0 > sf 0.9-6 > Reporter: Petr Bouchal > Assignee: Romain Francois > Priority: Major > Fix For: 3.0.0 > > > Hi all - thanks for the improvement addressed in ARROW-9271. > In arrow 2.0 spatial data (class sf) now retains metadata at column level, > but still does not roundtrip correctly as metadata (attributes) are lost at > the level of individual elements of the list-columns; at least I think that > is the problem as that is where I can see changes in the metadata.) Is this > something that is addressable? > See reprex below on what happens + what attributes exist at the element level. > FWIW a workaround with spatial data using sf would be to convert to WKT > before writing it out (sf::st_as_text()). It might be useful to note this > somewhere in the docs. > This is using arrow 2.0 and sf 0.9-6. > Reproducible example: > {code:R} > library(arrow) > #> > #> Attaching package: 'arrow' > #> The following object is masked from 'package:utils': > #> > #> timestamp > library(sf) > #> Linking to GEOS 3.8.1, GDAL 3.1.1, PROJ 6.3.1 > fname <- system.file("shape/nc.shp", package="sf") > df_spatial <- st_read(fname) > #> Reading layer `nc' from data source > `/Users/petr/Library/R/4.0/library/sf/shape/nc.shp' using driver `ESRI > Shapefile' > #> Simple feature collection with 100 features and 14 fields > #> geometry type: MULTIPOLYGON > #> dimension: XY > #> bbox: xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965 > #> geographic CRS: NAD27 > write_parquet(df_spatial, "spatial.parquet") > roundtripped <- read_parquet("spatial.parquet") > roundtripped > #> Simple feature collection with 100 features and 14 fields > #> geometry type: MULTIPOLYGON > #> dimension: arrow_list > #> bbox: xmin: -84.32385 ymin: 33.88199 xmax: -75.45698 ymax: 36.58965 > #> geographic CRS: NAD27 > #> First 10 features: > #> Error in vapply(lst, class, rep(NA_character_, 3)): values must be length > 3, > #> but FUN(X[[1]]) result is length 1 > attributes(roundtripped$geometry[[1]]) > #> $class > #> [1] "arrow_list" "vctrs_list_of" "vctrs_vctr" "list" > #> > #> $ptype > #> <list<double>[0]> > attributes(df_spatial$geometry[[1]]) > #> $class > #> [1] "XY" "MULTIPOLYGON" "sfg" > {code} -- This message was sent by Atlassian Jira (v8.3.4#803005)