Reproject sf object r

 

xy <- as. I need to transform the crs of the raster to match the crs of the sf data (vice versa would also be ok, but I’d prefer to get rid of the MODIS sinusoidal system). 1 Mar 23, 2019 · Most of the functions from the dplyr or tidyverse work well on the sf object. 6 Lab Assignment; 2 Spatial data manipulation in R. plot arrows in SF polygon. layer. Functions to transform, or reproject spatial objects typically take the following two arguments: the spatial object to reproject; a CRS object with the new projection definition; You can reproject. Details. j. An object of class bbox of length 4. The process should be something like: shp = "/path/to/data. False_Northing: 3210000,000000. e. May 29, 2024 · Methods to create a SpatVector from a filename or other R object. a numeric vector of length four, with xmin, ymin, xmax. epsg: The projection (currently only: "3031", or "3995"). If out_fmt="shp", the ESRI Shapefile driver truncates variable names to 10 characters or less. r. 6. logical value controlling the handling of unprojectable points. We can do the transformation of the previous section by first creating a target grid: and then warping the old raster to the new. The file is ~1. 25 -9. Sep 2, 2018 · Big fan of the sf (and previously, sp) spatial packages in R. This vignette describes how simple feature geometries can be manipulated, where manipulations include. You could approach this using more modern tools that give you a lot more flexibility. character vector; see details below. I used the sf package to get a CRS for my coordinates. The coordinate system information can be entered in several different ways. method: character. The input raster projection is Lambert Azimuthal; the parameters are here: Coordinate System: Lambert_Azimuthal_Equal_Area. spTransform therefore is doing nothing, since it's trying to reproject from epsg:4326 to epsg:4326. st_crs() - The CRS (spatial projection Coerce a bounding box to a sfc POLYGON object Description. Currently not supported. May 31, 2016 · I have an extent object that I would like to re-project to lat and lon. Using st_write. Functions for querying and reprojecting CRSs are demonstrated below with reference to cycle_hire_osm, an sf object from spData that represents ‘docking stations’ where you can hire bicycles in London. Spatial Data in Text Format Default for read_sf or R version >= 4. two-, three- or four-column numeric matrix, or object that can be coerced into a matrix; columns 3 and 4 contain z and t values. aggregate. 0 is FALSE, for st_read and R version < 4. Improve this answer. path. Even better, {sf} spatial objects are simply data. Object of class crs, which is a list with elements input (length-1 character) and wkt (length-1 character). 4 strings’ (or ‘proj4strings’), referring to the long-standing version 4 of the PROJ library. 0. If TRUE, geometries that can only partially be represented in the output crs are included in the output. Spatial Data in Text Format Feb 13, 2018 · An other solution is to force R to assign the projection via the epsg code when you import the data in R to ensure that the right projection will be used: SF <- read_sf(your_layer, crs = 28992) This will cause the following warning that can be ignored here because indeed we don't want to reproject this data: This episode will review how to import spatial points stored in . Spatial Data in Text Format Jun 24, 2021 · I had previous functioning R code that took an interpolated dataset of class sf, and turned it into a raster. To use the projectRaster function, we need to define two things: the object we want to reproject and. lst consist of 19 raster stacks like this: May 16, 2020 · Which shouldn't be that surprising as you're using a library that predates R itself, coming from the language S. Specifically, I have a map of average spring temperatures in Europe (Object A) and I want to crop it using a separate stars object containing presence of deciduous May 29, 2024 · column elements to be binded into an sf object or a single list or data. st_crs(nc) May 11, 2018 · 3. ggplot2. csv (Comma Separated Value) format into R as an sf spatial object. sf aggregate an sf object Description aggregate an sf object, possibly union-ing geometries Usage ## S3 method for class ’sf’ aggregate(x, by, FUN,, do_union = TRUE, simplify = TRUE, join = st_intersects) Arguments x object of classsf by either a list of grouping vectors with length equal to nrow(x)(seeaggregate), or May 24, 2018 · Transform a Multipolygon SF object in R from XY coordinates to lat/lon. In this example, the input geotiff was in a NAD83 geographic coordinate system and I reproject to a NAD 83 UTM 15 projected coordinate system. 1 Occasionally you may have to change the coordinates of your spatial object into a new Coordinate Reference System (CRS). </p> Alternatively, you can provide a coordinate reference system (CRS) description. When performing this operation in ArcMap using the Project tool, the default Geographic Transformation is NAD_1983_HARN_To_WGS_1984_2 (WKID 1900, accuracy 0. type transformations (e. This has given us the metadata about the file, but has not read it into R’s memory. 10 m). st_as_sfc has a Feb 14, 2019 · 3,656 5 29 54. i. op to. I am using a calculated bounding box based EPSG: 28992: sf::st_bbox(xmin = 187470, xmax =194587, ymin = 409753, ymax = 412715, crs = st_crs(28992)) It looks like you are not actually reading in the shapefile into R. Sep 23, 2020 · You can create an sf object from a SpatVector like this: s <- sf::st_as_sf(v) To go in the other direction to create SpatVector from an sf: vv <- vect(s) 1. Feb 11, 2016 · I'm trying to change raster projection using R and the raster package. Spatial Data in Text Format May 29, 2024 · Format. 75 Now let’s crop and reproject it, it looks almost identical to reprojecting a polygon in sf:. >outer_extent outer_extent class : Extent xmin : -5559753 xmax : -4447753 ymin : -4447852 ymax : -3335852 sf. Its also not a raster file. logical, default FALSE; if TRUE drop the geometry column and return a data. Feb 23, 2020 · I have read my raster data using r &lt;- raster("F:\\\\Studies\\\\Whole2015. It is not possible to use st_transform() to transform it to another CRS. Below, I used the slice function to split the nc object to nc1 and nc2. Radius of rounded corners. File path, default is the current working directory. When readOGR is used to import these data this information is automatically linked to the R spatial object. table is a list of list so ggplot is complaining st_can_transform returns a boolean indicating whether coordinates with CRS src can be transformed into CRS dst. 1st Qu. new nc. new ## stars object with 2 dimensions and 1 attribute Jul 8, 2021 · They are used by most geospatial tools, including the key geospatial R packages rgdal, sp, sf, stars, terra and raster. , POLYGON to MULTIPOLYGON) affine transformation (shift, scale, rotate) transformation into a different coordinate reference system. the CRS that we want to reproject it to. Create a sfc object from the coordinates of a bounding box. You can use a data. max. The other, df_raster, is a raster file" Firstly, df_raster is not a data frame. The above code looks more like you just clone shp into shputm and then assign the output of crs(shp) to shputm without performing an actual reprojection. Author(s) Tracey S. It tries to be complete about the plot methods sf provides, and give examples and pointers to options to plot simple feature objects with other packages (mapview, tmap, ggplot2). sf_add_proj_units loads the PROJ units link, us_in, ind_yd, ind_ft, and ind_ch into the udunits database, and returns TRUE invisibly on success. Nov 21, 2023 · I'm looking for a way to extract/infer a polygon from some sf object, that describes an outline that encompasses valid data. Viewed 3k times 5 I am trying to Apr 29, 2022 · 1. Name of the shapefile, without the . Here is an example: xlim = c(-3200, 4500), ylim = c(-4900, 4900)) # I need it in north easting! Because sf extends base R plotting methods plot()’s arguments such as main = (which specifies the title of the map) work with sf objects (see ?graphics::plot and ?par). The first argument is the spatial dataset to reproject. But neither the sf or the sfc objects currently exist. You should therefore probably just remove this line: Keep this in mind as we work with raster data. object of class sf. Using the PROJ. utm <- spTransform(xy, CRS("+proj=utm +zone=31N +datum=WGS84")) However it doesnt allow me to use the function proj4strong for a dataframe to convert the coordinates. Usage bbox_to_poly(bbox = NA, xmin = NA, ymin = NA, xmax = NA, ymax = NA, crs = 4326) Arguments Mar 2, 2024 · 1. Reprojecting geographic data. x. Examples. geometry. When I use sf::st_transform(), the results do not match. Ask Question Asked 7 years, 3 months ago. The sample output from the USAboundaries dataset looks like this: First, let’s open a connection to our COG, which is stored in the cloud. Default is 100, therefore care should be exercised when The st_transform() function is used to reproject sf objects. character description of target CRS, or object of class crs. 1 RasterStack vs RasterBrick; 1. Value. Oct 13, 2017 · In your code: you are overwriting the original projection of BatRange_data to lat/long before trying to reproject it. For the Second Edition of Geocomputation with R, due for publication in 2022, see geocompr. plot = 14) Switching between vector and raster in stars objects. you don't want to reproject to "NEW YORK LONG ISLAND STATE PLANE PROJECTION " as stated in your question (and which by the way seems to be the projection of your input), but to lat/lon 4326. names for the created sf object. , +proj=longlat +datum=WGS84 ), or an EPSG code (e. In Geospatial Sciences we’re constantly working with spatial datasets that come in many different projections. 1 Transform or reproject sf objects; 1. 4 or with a WKT string epsg: reads the epsg code from the header. 1. It seems that raster is now throwing errors. To do this, we need to pass a URL to the file’s online location to terra. I see spTransform and st_transform as methods to reproject a spatial object into a new space. The sp package in R, by default often uses the proj4 format to define CRS of an object. variable selection, see [. Jul 3, 2019 · Warning message: Computation failed in stat_sf(): no applicable method for 'st_bbox' applied to an object of class "list" I guess my problem is happening as the slocationzone column of my data. number of colors breaks (ignored for factor or character variables) breaks. 1) Provide a crs argument, and, optionally, a res argument, but do not provide a to argument. point_sf <- st_set_crs(point_sf, 4326) In this other line of code, the function, st_set_crs(), retrieves a coordinate reference system from sf or sfc objects. Figure 2. GCS_ETRS_1989. May 13, 2021 · the object we want to reproject and. and ymax values; if obj is of class sf, sfc, Spatial or Raster, the object returned has a class bbox, an attribute crs and a method to print the bbox and an st_crs method to retrieve the coordinate reference system corresponding to obj (and hence the bounding box). either a numeric vector with the actual breaks, or a name of a method accepted by the style argument of classIntervals. Any suggestion to improve the process? my rstack. nbreaks. keep. st_crs(points) <- st_crs(polygons) Note: the points should be registered in the same coordinate system, of course. frame(events) coordinates(xy) proj4string(xy) <- CRS("+proj=longlat +datum=WGS84") events. plot = 14 to plot ## all. Also, all binary operations st_op2(x,y) called with a single argument, as st_op2(x), are handled as st_op2(x,x). Feb 13, 2020 · You need to reproject your points as well; sf::st_transform() should do the job. Each polygon's centroid (Inside_X & Inside_Y) was calculated in arcmap (Example: X: 32570914 Y: 5791442). 4 (e. fun. I'm using ggplot2 to plot a projected polygon (sf) object. Note: this is the first edition of Geocomputation with R, first published in 2019 and with minor updates since then until summer 2021. As it says in the examples: st_crs(x) <- value. The syntax is projectRaster(RasterObject, crs = CRSToReprojectTo) We want the CRS of our hillshade to match the DTM_HARV raster. To solve your problem you can use: Oct 1, 2018 · It is actually faster than velox and coercing to a different object class is not necessary as the exact_extract function operates on raster class objects. Defaults to 0. 5 Raster data in R. #create an extent object ext2 <- st_bbox(r) #constrain it in x direction ext2[1] <- 120 ext2[3] <- 170 r2 <- st_crop(r, ext2) r3 <- st_transform(r2, "+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs +towgs84 Creating an sf object from the maps package. 15 lines. We’ve previously shown how R can be used to read in spatial data, reproject spatial data, and resample spatial datasets. I was able to get some census data from the cancensus package and demonstrate how you might crop it here: get data as sf object: Create a box first by converting the extent object to SpatialPolygons then to sf object and set crs to 4326: Finally use st_intersection: Here is the cropped census data: There are two approaches you can follow to project the values of a Raster object. frame to make a SpatVector of points; or a "geom" matrix to make a SpatVector of any supported geometry (see examples and geom ). so (of course) nothing changes. . If sf object has more than 1 record, it will be returned but not exported. However, I have a case where I have a complicated spatial polygon object centered on a point. sf_add_proj_units() directly transform a set of coordinates. See the following reprex: Oct 20, 2021 · I am new-ish to using the stars package in R and I am having trouble with figuring out how to create a stars object C that has the values from object A but the extent of object B. To retrieve the CRS for a spatial object: proj4string(x) To assign a known CRS to spatial data: Jun 4, 2024 · This episode will review how to import spatial points stored in . The second argument is the coordinate system into which the data will be reprojected. 1 Sep 9, 2019 · I downloaded the USAboundaries library in R, and so I think I have enough data to create the polygons in leaflet, but the data is not in the SpatialPointsDataFrame format. You can use an existing object, or use projectExtent for this or an existing Raster* object. net. CRS in R for sp classes: Some spatial data files have associated projection data, such as ESRI shapefiles. 1 Attribute Join. palette function, similar to rainbow, or palette values; if omitted, sf. record selection, see [. A filename can be for a shapefile or any spatial file format. Latitude_Of_Origin: 52,000000. As we discussed in the Open and Plot Shapefiles in R episode, we can view metadata associated with an R object using: st_geometry_type() - The type of vector data stored in the object. This is a good thing because sf provides a unified solution to most of the geospatial operations that are often used within R. Size of label border, in mm. This CRS contains the datum, units and other information that R needs to reproject your data. frames or matrices to SpatialPointsDataFrame objects. Mar 8, 2019 · The result of the function st_bbox() is of class bbox. 8GB so it would do bad things if we tried to read the whole thing in…. nc. Support for simple features, a standardized way to encode spatial vector data. Let’s Sep 24, 2018 · The sf package is the successor to the common suite of geospatial analysis packages for R: sp, rgdal, and rgeos. frame with such columns; at least one of these columns shall be a geometry list-column of class sfc or be a list-column that can be converted into an sfc by st_as_sfc. 50 -72. I guessed on the crs. stringsAsFactors() int64_as_string logical; if TRUE , Int64 attributes are returned as string; if FALSE , they are returned as double and a warning is given when precision is lost (i. st %>% st_warp(newgrid) -> nc. Sep 3, 2019 · When you reproject the data, you specify the CRS that you wish to transform your data to. Note that the function may warn about the incorrectness of the main. epsg. data. sf = st_xy2sfc (x, as_points = TRUE) x. A function that takes a sfc object and returns a sfc_POINT with the same length as the input. 1. Binds to 'GDAL' for reading and writing data, to 'GEOS' for geometrical operations, and to 'PROJ' for projection conversions and datum transformations. Therefore, it is possible to use R to address all your data processing needs in a single environment without the need to move between tools for tabular main. 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. The default plot of an sf object is a multi-plot of all attributes, up to a reasonable maximum: plot (nc) ## Warning: plotting the first 9 out of 14 attributes; use max. proj4string: +proj=longlat +datum=WGS84 +no_defs. We will also reproject data imported from an ESRI shapefile format, export the reprojected data as an ESRI shapefile, and plot raster and vector data as layers in the same plot. I don't have access to the {albersusa} package, so I am using {USABoundaries} to get a map of the lower 48, but that is not the point; the point is applying st_transform(crs = crs_use) to both your spatial objects before plotting. Projection issues point over multipolygon data sf objects. row. sf ## stars object with 2 dimensions and 1 attribute ## attribute(s): ## Min. You have to use st_set_crs to set the coordinate-system of the original shapefile and then use st_transform to transform to 32736. size. frame, or a sf object to work with the op argument. Apr 27, 2024 · Say I have a MODIS LAI raster and a simple feature (sf) object (points) with two different crs. colors is used. Sep 9, 2020 · And since there is no sfc object, the next line of code does not work. All geometrical operations st_op(x) or st_op2(x,y) work both for sf objects and for sfc objects x and y; since the operations work on the geometries, the non-geometry parts of an sf object are simply discarded. nc1 <- nc %>% slice(1:50) nc2 <- nc %>% slice(51:100) # Print the crs of nc, nc1, and nc2. I only have limited experience with sf, so any advice aside from an answer is appreciated too. If NULL, function(x) sf::st_point_on_surface(sf::st_zm(x)) will be used. g. The projection (currently only: "3031", or "3995" ). 4 syntax, you specify the complete set of parameters including the ellipse, datum, projection units and projection definition that define a particular CRS. frame. Mar 13, 2020 · Note that the sf package is moving towards the more concise EPSG format. The default for the layer name is the basename (filename without path) of the the data source name. Jun 16, 2020 · I have one more question regarding the transformation of the events. 9. label. Uses by default the 's2' package for spherical geometry operations on ellipsoidal (long Mar 12, 2024 · This episode will review how to import spatial points stored in . shp" # class(shp) is character shp = st_read(shp) # class(shp) is now an sf data frame shp = st_transform(shp, newcrs) # show is now transformed and I think you are missing the second step there. I have a shapfile in R which I want to use to calculate the K nearest neighbor. As attributes are typically stored in data. We will also reproject data imported from a shapefile format, export this data as a shapefile as well as plot raster and vector data as layers in the same plot. shp") The file name is taken as the data source name. with a warning when not all attributes can be reasonably plotted. We can thus assign the CRS of our DTM_HARV to our hillshade within the projectRaster() function as follows: crs = crs(DTM_HARV). . frame objects (or the very similar tbl_df ), we will also store feature The sf or stars object to be re-projected. Mar 29, 2019 · I have a big list of raster stacks and I want to reproject and then clip them in R. One, df_points, has spatial information saved as points. 5) knitr::opts_chunk\) set(fig. A good reference for Proj4 format projections, which are used by RGDAL, can be found at spatialreference. When I use it, ggplot is ploting the axis as degrees (north/south - east/west), however I prefer that it keeps the axis as northing-easting (which is the correct). 2 Attribute Selection (or non-spatial subsetting) 2. robinlovelace. False_Easting: 4321000,000000. st_bbox() - The spatial extent (geographic area covered by) of the object. a numeric vector of length four, with xmin, ymin, xmax and ymax values; if obj is of class sf, sfc, Spatial or Raster, the object returned has a class bbox, an attribute crs and a method to print the bbox and an st_crs method to retrieve the coordinate reference system Uses read_sf in package 'sf' to read a river shapefile, and establishes connectivity of segment endpoints based on spatial proximity. You can use st_crs. In your case it would probably be. I have done the same procedure in ArcGIS using batch processing which was significantly faster. plot. 3. It updates the header of the LAS object either with the EPSG code for LAS formats < 1. Its an object of class "RasterLayer" (and "Raster" and "BasicRaster") from the raster package. Modified 5 years, 6 months ago. drop. You can use the following formats to define coordinate reference systems: WKT, PROJ. agr. , values are larger than 2^53). tolerance. 1 How to do this in sf; 2. title for plot ( NULL to remove) pal. geom_sf in ggplot is designed to work with spatial objects, ideally in sf format, but it is easy to convert between different kinds of spatial Spatial Plots with. wkt: reads the WKT string from the header. pts. , "epsg:4326" ). shp extension. But note that the PROJ. frame, else make the geometry sticky and return a sf object. ⁠st_crs<-⁠: assigns a CRS from a CRS (sp), a crs (sf), a WKT string, a proj4string or an epsg code. See ?"SpatialPointsDataFrame-class" for more on how to convert simple data. Snapping tolerance of segment endpoints to determine connectivity. Mar 2, 2024 · 1. Features that cannot be transformed are returned as empty geometries. 5 illustrates this flexibility by overlaying circles, whose diameters (set with cex =) represent country populations, on a map of the world. I then preformed an average of raster values over specific overlayed polygons. Uses by default the 's2' package for spherical geometry operations on ellipsoidal (long/lat) coordinates. My event data is the format of a dataframe. Transforms coordinates of object to new projection. A st_crs() returns a sf::crs. You can supply a list of SpatVectors to append them into a single Warping a raster means creating a new regular grid in a new CRS, based on a (usually regular) grid in another CRS. nrow() - The number of features in the object. 25 181. Also, since coercion is not necessary for exact_extract , cropping the raster data to the extent of the polygons is not necessary and would actually slow things down. Since long, coordinate reference systems in R (and many other tools) have been represented by so called ‘PROJ. plot (nc, max. Elements may be NA valued; if all elements are NA the CRS is missing valued, and This vignette describes the functions in sf that can help to plot knitr::opts_chunk \(set(fig. stringsAsFactors. sf: Simple Features for R. The syntax is project (RasterObject, crs) We want the CRS of our hillshade to match the DTM_HARV raster. 4. 5. st_bbox(r) ## xmin ymin xmax ymax ## 82. partial: logical. The spTransform() function requires two inputs: the name of the object that you wish to transform; the CRS that you wish to transform Jun 4, 2024 · To use the project () function, we need to define two things: the object we want to reproject and. Let's say I have some data in some unusual projection. Share. width = 6) simple features. – Wimpel. Anyway, if you import both the shapefile and the NDVI raster, and then reproject shp using spTransform, subsequent data extraction should work out fine. It is not going well in R. 2. names. org. One can increase the maximum number of maps to be plotted by. May 29, 2024 · sf-package: sf: Simple Features for R; sf_project: directly transform a set of coordinates; sgbp: Methods for dealing with sparse geometry binary predicate st: Create simple feature from a numeric vector, matrix or list; st_agr: get or set relation_to_geometry attribute of an 'sf' object; stars: functions only exported to be used internally Nov 18, 2021 · "I have two dataframes in R. epsg (SRID): 4326. 0 equal to default. # Split the nc object to two sf objects. Sep 5, 2013 · To ensure that appropriate projection metadata are at every step associated with the coordinates, I'd suggest converting the points to a SpatialPointsDataFrame object as soon as possible. We can convert a raster dimension to a vector dimension while keeping other dimensions as they are in a stars object by. Central_Meridian: 10,000000. If not, you would have to find out the correct coordinate system for them and then use st_transform to put them into the Chapter 6. Method used for estimating the new cell values of a The st_write (sf) function is called. Frescino Examples May 8, 2018 · 12. Optional input as an sf object, if shapefile has already been read into the R environment. 3 Spatial Query. We can thus assign the CRS of our DTM_HARV to our hillshade within the project () function as follows 3 days ago · If x is a SpatVector, you can provide a crs definition as discussed above, or any other object from which such a crs can be extracted with crs. height = 4. 2) Create a template Raster with the CRS you want to project to. Variable names are changed before export using an internal function (trunc10shp). Once a spatial dataset can be stored in R as a data frame, we can use ggplot to Oct 23, 2023 · obj: The sf or stars object to be re-projected. a sf object with st_transform() Sep 15, 2020 · I wrote an R script to automate work that was being done in ESRI ArcMap. The way you interact with spatial data in the sf universe is more intuitive than in the past because the structure of the sf class in R is very simple Aug 20, 2020 · Stack Overflow Public questions & answers; Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Talent Build your employer brand This tutorial will review how to import spatial points stored in . For this, st_write() needs to guess the driver. 4 Reprojecting or Projection Transform. frames with a geometry column, so all of the tidy, wrangle, join, and plot capabilities from {dplyr} and {ggplot2} also work on {sf} objects. you first say the coordinates are 32736: st_set_crs(32736), and the you transform to the same coordinates; st_transform(crs=32736) . NA_bbox_ represents the missing value for a bbox object Value. tif") class(r) &gt; class(r) [1] "RasterLayer" attr(,"package") [1] "raster" How can I Simple features are implemented as R native data, using simple data structures (S3 classes, lists, matrix, vector). If keep is TRUE, then such points will yield Inf or -Inf in the return value Jul 14, 2015 · This is how you can reproject a raster in R using the raster package. 1 Using the sf package; 2. 4 notation has been deprecated, and you can only use it with the WGS84/NAD83 and Mar 3, 2020 · st_as_sf will take your lat and lon coordinates that we created in the previous step and convert to an sf object. To write a simple features object to a file, we need at least two arguments, the object and a filename: st_write(nc, "nc1. Typical use involves reading, manipulating and writing of sets of features, with attributes and geometries. This is why your extent is not changing. uj tj hp mx kq ns pi ko ux sd