Commit: c2dc1be9243fb86daebdcc332f02d30c5189d32a - myprojects-hg-reborn (hg)

Commit MetaInfo

• Revisión: c2dc1be9243fb86daebdcc332f02d30c5189d32a (tree)
• Tiempo: 2025-01-17 21:32:00
• Autor: Lorenzo Isella <lorenzo.isella@gmai...>
• Commiter: Lorenzo Isella

Log Message

This script run queries on data.europa.eu and return the result as a tibble.

Cambiar Resumen

• add: R-codes/europa_rectangular_data.R

Diferencia incremental

diff -r 5d36c5e195f3 -r c2dc1be9243f R-codes/europa_rectangular_data.R
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/R-codes/europa_rectangular_data.R	Fri Jan 17 13:32:00 2025 +0100
@@ -0,0 +1,83 @@
+# Load necessary libraries
+library(httr)
+library(jsonlite)
+library(dplyr)
+library(purrr)
+
+# Function to query the data.europa.eu SPARQL endpoint and return results as a list
+query_data_europa_list <- function(query, endpoint = "https://data.europa.eu/sparql") {
+  # Send the query using POST and the httr package
+  response <- POST(
+    url = endpoint,
+    body = list(query = query),
+    encode = "form"
+  )
+  
+  # Check if the status code is 200 (successful)
+  if (status_code(response) == 200) {
+    # Parse and return the JSON content as a list
+    result <- content(response, "parsed", type = "application/json")
+    return(result$results$bindings)  # Return the "bindings" part of the result as a list
+  } else {
+    stop("Query failed with status code: ", status_code(response))
+  }
+}
+
+# Function to convert a list of SPARQL bindings into a tibble
+convert_list_to_tibble <- function(bindings_list) {
+  if (length(bindings_list) == 0) {
+    return(tibble())  # Return an empty tibble if the list is empty
+  }
+  
+  # Extract fields using purrr::map() and create a tibble
+  tibble(
+    dataset = map_chr(bindings_list, ~ .x$dataset$value),
+    title = map_chr(bindings_list, ~ .x$title$value),
+    description = map_chr(bindings_list, ~ .x$description$value)
+  )
+}
+
+# Example SPARQL query to get datasets related to "climate change"
+query_climate_change <- "
+PREFIX dcat: <http://www.w3.org/ns/dcat#>
+PREFIX dcterms: <http://purl.org/dc/terms/>
+
+SELECT ?dataset ?title ?description
+WHERE {
+  ?dataset a dcat:Dataset ;
+           dcterms:title ?title ;
+           dcterms:description ?description .
+  FILTER(CONTAINS(LCASE(?title), 'climate change'))
+}
+LIMIT 5
+"
+
+# Query to fetch all datasets (example query)
+query_all_datasets <- "
+PREFIX dcat: <http://www.w3.org/ns/dcat#>
+PREFIX dcterms: <http://purl.org/dc/terms/>
+
+SELECT ?dataset ?title ?description
+WHERE {
+  ?dataset a dcat:Dataset ;
+           dcterms:title ?title ;
+           dcterms:description ?description .
+}
+LIMIT 10
+"
+
+# Run the queries and return the results as a list
+result_climate_change_list <- query_data_europa_list(query_climate_change)
+result_all_datasets_list <- query_data_europa_list(query_all_datasets)
+
+# Convert list results into tibbles
+tibble_climate_change <- convert_list_to_tibble(result_climate_change_list)
+tibble_all_datasets <- convert_list_to_tibble(result_all_datasets_list)
+
+# Display the tibbles
+cat("Tibble for Climate Change Related Datasets:\n")
+print(tibble_climate_change)
+
+cat("\nTibble for All Datasets (First 10):\n")
+print(tibble_all_datasets)
+