简单要素线串集合在 R 传单中不可见

Question

sf我正在尝试使用和在 R 中显示（断开连接的）线串的简单特征集合leaflet。数据是从 openstreetmap 获取的osmdata。

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使用基本的plot()函数，tmap， 或mapview，我可以直接在静态和交互式地图上显示线串。但是，这在使用时不起作用leaflet。Leaflet 正确地将地图居中，但不显示线串。在 addPolyLines() 中摆弄颜色、重量等参数似乎没有帮助。

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雷普莱克斯

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library(osmdata)\nlibrary(leaflet)\nlibrary(sf)\nlibrary(tmap)\n\nosm <- opq(bbox = c(-0.27, 51.47, -0.20, 51.50)) %>%\n  add_osm_feature(key = \'name\', value = "Thames", value_exact = FALSE) %>%\n  osmdata_sf()\n\nosm$osm_lines\n\nSimple feature collection with 2085 features and 178 fields\ngeometry type:  LINESTRING\ndimension:      XY\nbbox:           xmin: -2.029917 ymin: 51.37841 xmax: 0.6778926 ymax: 51.79032\nepsg (SRID):    4326\nproj4string:    +proj=longlat +datum=WGS84 +no_defs\nFirst 10 features:\n...\n\nplot(osm$osm_lines, max.plot = 1) # OK\nqtm(osm$osm_lines) + tm_lines() # OK\nmapview(osm$osm_lines) # OK\n\nleaflet(osm$osm_lines) %>% # not OK (grey)\n  addPolylines()\n

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会话信息

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> library(sf)\nLinking to GEOS 3.6.1, GDAL 2.2.3, proj.4 4.9.3\nWarning message:\n  package \xe2\x80\x98sf\xe2\x80\x99 was built under R version 3.4.4 \n\n> sessionInfo()\nR version 3.4.3 (2017-11-30)\nPlatform: x86_64-w64-mingw32/x64 (64-bit)\nRunning under: Windows >= 8 x64 (build 9200)\n\nMatrix products: default\n\nlocale:\n  [1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252    LC_MONETARY=English_United States.1252 LC_NUMERIC=C                          \n[5] LC_TIME=English_United States.1252    \n\nattached base packages:\n  [1] stats     graphics  grDevices utils     datasets  methods   base     \n\nother attached packages:\n  [1] tmap_1.11-2   sf_0.6-3      leaflet_2.0.1 osmdata_0.0.7\n\nloaded via a namespace (and not attached):\n  [1] httr_1.3.1         viridisLite_0.3.0  jsonlite_1.5       splines_3.4.3      geojsonlint_0.2.0  foreach_1.4.4      R.utils_2.6.0      gtools_3.5.0      \n[9] shiny_1.1.0        expm_0.999-2       sp_1.3-1           stats4_3.4.3       yaml_2.1.19        LearnBayes_2.15.1  lattice_0.20-35    digest_0.6.15     \n[17] RColorBrewer_1.1-2 promises_1.0.1     rvest_0.3.2        colorspace_1.3-2   plyr_1.8.4         htmltools_0.3.6    httpuv_1.4.3       Matrix_1.2-12     \n[25] R.oo_1.22.0        XML_3.98-1.11      rmapshaper_0.4.0   raster_2.6-7       gmodels_2.16.2     xtable_1.8-2       webshot_0.5.0      scales_0.5.0      \n[33] gdata_2.18.0       satellite_1.0.1    later_0.7.3        gdalUtils_2.0.1.14 mapview_2.4.0      magrittr_1.5       mime_0.5           deldir_0.1-15     \n[41] R.methodsS3_1.7.1  nlme_3.1-131       MASS_7.3-47        xml2_1.2.0         class_7.3-14       tools_3.4.3        geosphere_1.5-7    stringr_1.3.1     \n[49] V8_1.5             munsell_0.5.0      compiler_3.4.3     e1071_1.6-8        classInt_0.2-3     units_0.6-0        grid_3.4.3         tmaptools_1.2-4   \n[57] RCurl_1.95-4.10    dichromat_2.0-0    iterators_1.0.9    htmlwidgets_1.2    crosstalk_1.0.0    bitops_1.0-6       base64enc_0.1-3    boot_1.3-20       \n[65] codetools_0.2-15   DBI_1.0.0          jsonvalidate_1.0.0 curl_3.2           R6_2.2.2           lubridate_1.7.4    rgdal_1.3-2        rgeos_0.3-28      \n[73] spdep_0.7-7        KernSmooth_2.23-15 stringi_1.1.7      osmar_1.1-7        Rcpp_0.12.17       png_0.1-7          spData_0.2.8.3     coda_0.19-1  \n

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Answer 1

osmdata 具有命名功能，传单无法读取。请参阅https://github.com/ropensci/osmdata/issues/100

作为一种 hack，你可以将名称设置为 NULL：

osm_lines <- osm$osm_lines
names(osm_lines$geometry) <- NULL
leaflet(osm_lines) %>%
  addPolylines()