Questions tagged [r-sf]
The motivation behind the `sf` package is to provide a complete, standardized implementation of simple features in R, with links to GDAL, GEOS and Proj.4. There is a also https://gis.stackexchange.com/ for spatial R questions.
r-sf
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Is it possible to pass an SQL query that contains an SQL function to the query parameter of the st_read function in R's sf package? What alternative?
I have a shapefile and I want to load only the observations that satisfy some condition (to avoid unnecessarily loading the whole dataset). To do it using R's sf package, I have to pass to the query ...
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Transparent or uniform colour for outer-most Voronoi polygons in a figure
I'm trying to remove the outer polygons in a Voronoi diagram. The main plot looks like this:
require(ggplot2)
require(ggvoronoi)
set.seed(2023)
N <- 80
x <- runif(N)
y <- runif(N)
df <- ...
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R filling in a matrix with values from spatial data
I have a matrix in R called “habitat” with latitude as the rownames and longitude as the column names. The cells are filled with NA right now. My end goal is to have the whole matrix filled with ...
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How to get outline of sf object?
I'm looking for a way to extract/infer a polygon from some sf object, that describes an outline that encompasses valid data. I only have limited experience with sf, so any advice aside from an answer ...
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How to plot a map with south up using the ggplot2 and sf packages?
I am trying to plot a map with south up using the packages ggplot2 and sf.
I tried the functions coord_flip and scale_y_reverse, but I was not successful.
The base code I am using is:
library(...
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Error with M values and st_zm function in sf package
I have imported a multipolygon shp file containing different forest patches (called 'patch'):
patch
Then, I have bricked different Sentinel-2 bands for the same region in a raster called 'SenBel'
data:...
- 15
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Aggregate grid cells to larger resolution in sf
Consider a grid cell, where each cell is 10x10.
library(sf)
grid1 <- st_make_grid()
plot(grid1)
I would like to create another grid cell, based on grid1, where each cell is 30x30 and consists of ...
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Select random rows until threshold value from other column is reached
I have an SF-object in R. It looks as follows:
Type Value Geometry
A 1 ()
A 3 ()
B 2 ()
A 1 ()
C 4 ()
In the geometry column, the ...
- 421
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votes
1
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How to create a line from 2 sf objects
I have 2 shapefiles that have the same number of rows. I want to create a line for each row.
I can't figure out how to do it.
Here is my example code
library(sf)
#> Linking to GEOS 3.11.2, GDAL 3.6....
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How to create (using R's sf) a spatial data frame whose geometry column is the difference between the geometry columns of other two data frames?
I have two spatial data frames that I've loaded using the sf package in R. In the first data frame I have (61) US counties, while in the second I have a subpart of each of these (61) counties. Both ...
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How to transform a sf table to a stars cube with stars::st_as_stars function?
I want to transform a sf data.frame into a stars cube, and choose the dimensions.
But I don't succeed in using the function stars::st_as_stars properly and get what I want.
Why do I want to transform ...
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Weighted aggregation of stars object
I was wondering if it's possible to adjust the following code in such a way that the aggregate() function takes into account the overlapping area between each pixel defined in a stars object and the &...
- 3,630
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st_transform not accurately projecting connecting lines of a polygon
I am currently having an issue where I am trying to project rectangular polygons onto a map of North America. My issue stems from the fact that I am specifying the polygon in lat/long, then projecting ...
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Convert a vector grid created with sf::st_make_grid into a raster stack
I have a vector grid created with sf::st_make_grid() with several columns of
values. I would like to convert it to a raster stack, with each column of values becoming
a layer of the raster stack.
I ...
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How to add multiple points to map with tmap in R?
I'm learning how to make maps with R so I'm kinda new to all of this. I'm using tmap to plot a map (you can find the shp here https://www.data.rio/datasets/%C3%A1reas-program%C3%A1ticas-da-sa%C3%BAde/...
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