If x is numeric, return crs object for EPSG: x; if x is character, return crs object for x; if x is of class sf or sfc, return its crs object. Object of class crs, which is a list with elements input (length-1 character) and wkt (length-1 character).

I convert them to a sf object like so: roads <- st_as_sf(roads, crs = 27700) After conversion, the SRID is empty, and the proj4string (possibly) looks incorrect. Why is this? Can I fix it?

2020年11月30日 · 如果数据中没有坐标系，那么我们可以通过st_set_crs函数来指定它的坐标系，坐标系的表示方法有两种： 1、 P roj 4 ：由一长串字符串构成，比如"+proj=lcc +lat_0=0 +lon_0=105 +lat_1=30 +lat_2=62 +x_0=0 +y_0=0 +ellps=krass +units=m +no_defs"

2024年10月11日 · Set or replace retrieve coordinate reference system from object. st_crs(x, ...) format(x, ...) ... one of (i) character: a string accepted by GDAL, (ii) integer, a valid EPSG value (numeric), or (iii) an object of class crs. logical; specify whether axis order should be handled compliant to the authority; if omitted, the current value is printed.

2018年5月8日 · I'm trying to define the right CRS for my sf object. I want to plot points atop the following layer (country: the Netherlands): output: This layer has the correct projection. But the POINT layer doesn't have the correct CRS project presumably because it has no proj4string?

If x is numeric, return crs object for EPSG: x; if x is character, return crs object for x; if x is of class sf or sfc, return its crs object. Object of class crs, which is a list with elements input (length-1 character) and wkt (length-1 character).

2023年9月6日 · crs 参数指定了sf对象的坐标参考系统，这里使用了WGS84坐标系统，其对应的EPSG代码为4326。 如果需要将坐标转换为其他坐标系统，可以使用st_transform函数。 这一步是可选的，根据实际需求来决定是否进行坐标转换。 1. crs 参数指定了目标坐标系统，这里使用了Web墨卡托投影坐标系统，其对应的EPSG代码为3857。 至此，我们完成了使用R语言的st_as_sf函数实现的流程。 下面是一个使用mermaid语法绘制的饼状图，展示了数据的分布情 …

传坐标系回转换后的sf对象，crs是EPSG code，4326为WGS84坐标系。st_crs()显示sf对象的坐标系信息。 6. intersect. 上一篇文章已经示范过了，见文章顶部链接。这里要补充的是intersect的两个对象的坐标系要相同。这里同样也报了个warning：

The abbreviation CRS stands for Coordinate Reference System. It defines how real locations on earth are projected on a two-dimensional surface (the plotting device or paper). Latitudes longitudes (WGS84) can also be seen as a CRS, but an unprojected one.

2020年4月20日 · st_transform() transforms the CRS, i.e., it changes it from one projection to another. You're looking for st_crs() <-or st_set_crs() –