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I'd be really happy if you could help me with this problem. I want to geom_point the df "daa_84" into the shp file "shp_5". After viewing multiple related questions on stackoverflow and testing their answers (as create a sp object from "daa_84" and transform UTM coordinates to match it with the coordinates of "shp_5"), I only get something like the plot. Also, I know that the UTM zone (19S) and the EPSG code related to my country (32719) of the coords system (WGS84) are needed for "something" haha. Any ideas?

> head(daa_84)
            # A tibble: 6 x 2
              utm_este utm_norte
                 <dbl>     <dbl>
            1   201787   6364077
            2   244958   6247258
            3   245947   6246281
            4   246100   6247804
            5   246358   6242918
            6   246470   6332356
            
    
    > head(shp_5)
            Simple feature collection with 6 features and 1 field
            geometry type:  MULTIPOLYGON
            dimension:      XY
            bbox:           xmin: -7973587 ymin: -3976507 xmax: -7838155 ymax: -3766040
            projected CRS:  WGS 84 / Pseudo-Mercator
                 Comuna                       geometry
            1 Rinconada MULTIPOLYGON (((-7871440 -3...
            2   Cabildo MULTIPOLYGON (((-7842610 -3...
            3   Petorca MULTIPOLYGON (((-7873622 -3...
            4 Panquehue MULTIPOLYGON (((-7874932 -3...
            5     Olmué MULTIPOLYGON (((-7916865 -3...
            6 Cartagena MULTIPOLYGON (((-7973501 -3...
            
        
        ggplot() + geom_sf(data = shp_5, aes()) + 
              geom_point(data = daa_84, aes(x= "utm_este", "utm_norte"),
                         alpha = 0.05, size = 0.5) + 
              labs(x = "Latitude", y = "Longitude")+
              theme_bw()

my progress so far

EDIT

in addition to the answer of william3031, this code also works

library(sf)
daa_84 = tribble(~utm_este, ~utm_norte,
201787,   6364077,
244958,   6247258,
245947,   6246281,
246100,   6247804,
246358,   6242918,
246470,   6332356)


daa_84 = st_as_sf(daa_84, 
                  coords=c('utm_este', 'utm_norte'), 
                  crs=st_crs(32719)) %>% 
      st_transform(st_crs(shp_5))
MPZ
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1 Answers1

0

This will work for you. I have used a different dataset for South America as you haven't provided a reproducible example.

library(tidyverse)
library(sf)
library(spData) # just for the 'world' dataset

# original
daa_84 <- data.frame(
  utm_este = c(201787L, 244958L, 245947L, 246100L, 246358L, 246470L),
  utm_norte = c(6364077L, 6247258L, 6246281L, 6247804L, 6242918L, 6332356L)
)

# converted
daa_84_sf <- st_as_sf(daa_84, coords = c("utm_este", "utm_norte"), crs = 32719)


# load world to get South America
data("world")
sam <- world %>% 
  filter(continent == "South America")

# plot
ggplot() +
  geom_sf(data = sam) + 
  geom_sf(data = daa_84_sf)

enter image description here

william3031
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