ch_get_url_data {CSHShydRology}

Gets remote data sets

Description

Accesses data sets, via a url the first time, saves them locally, then accesses them locally after the first time the script is executed.

Usage

ch_get_url_data(gd_url, gd_filename, quiet = FALSE)

Arguments

gd_url

url for accessing data set

gd_filename

name of file on local drive, including full path

quiet

Optional. If FALSE (the default) error/warning messages are printed if the data cannot be found.

Value

Returns a data frame (from a .csv file), a raster object (from a .tif file), or an sf object (from a GeoJSON file).

Author(s)

Dan Moore

Examples

# Example not tested automatically as multiple large data files are downloaded which is slow

# Tested using files in the Upper Penticton Creek
# zenodo repository https://zenodo.org/record/4781469
library(ggplot2)
library(raster)

# create directory to store data sets
dir_name <- tempdir(check = FALSE)
if (!dir.exists(dir_name)) {
  dir.create(dir_name)
}
 
# test with soil moisture data in csv format
sm_fn <- file.path(dir_name, "sm_data.csv")
sm_url <- "https://zenodo.org/record/4781469/files/sm_data.csv"
sm_data <- ch_get_url_data(sm_url, sm_fn)
head(sm_data)

# test with tif/tiff file containing a dem
ra_fn <- file.path(dir_name, "gs_dem25.tif")
ra_url <- "https://zenodo.org/record/4781469/files/gs_dem25.tif"
ra_data <- ch_get_url_data(ra_url, ra_fn)
plot(ra_data)

# test with GeoJSON
gs_fn <- file.path(dir_name, "gs_soilmaps.GeoJSON")
gs_url <- "https://zenodo.org/record/4781469/files/gs_soilmaps.GeoJSON"
gs_data <- ch_get_url_data(gs_url, gs_fn)

ggplot(gs_data) +
  geom_sf(aes(fill = new_key)) +
  labs(fill = "Soil class",
       x = "UTM Easting (m)",
       y = "UTM Northing (m)") +
  coord_sf(datum = 32611) +
  theme_bw()