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## ----include=FALSE------------------------------------------------------------
options(rdf_print_format = "nquads")
is_linux <- Sys.info()["sysname"] == "Linux"
knitr::opts_chunk$set(eval=FALSE)
## ----message = FALSE, warning=FALSE-------------------------------------------
# library(rdflib)
# library(dplyr)
# library(tidyr)
# library(tibble)
# library(jsonld)
## -----------------------------------------------------------------------------
# car_triples <-
# mtcars %>%
# rownames_to_column("Model") %>%
# gather(attribute,measurement, -Model)
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(car_triples)
## -----------------------------------------------------------------------------
# car_triples <-
# mtcars %>%
# rownames_to_column("Model") %>%
# rowid_to_column("subject") %>%
# gather(predicate, object, -subject)
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(car_triples)
## -----------------------------------------------------------------------------
# iris_triples <- iris %>%
# rowid_to_column("subject") %>%
# gather(key = predicate, value = object, -subject)
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(iris_triples)
## -----------------------------------------------------------------------------
# iris_triples <- iris %>%
# rowid_to_column("subject") %>%
# mutate(subject = paste0("http://example.com/", "iris#", subject)) %>%
# gather(key = predicate, value = object, -subject)
#
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(iris_triples)
## ----mesage = FALSE-----------------------------------------------------------
# iris_triples <- iris %>%
# rowid_to_column("subject") %>%
# mutate(subject = paste0("http://example.com/", "iris#", subject)) %>%
# gather(key = predicate, value = object, -subject) %>%
# mutate(predicate = paste0("http://example.com/", "iris#", predicate))
#
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(iris_triples)
## -----------------------------------------------------------------------------
# rdf <- rdf()
## -----------------------------------------------------------------------------
# base <- paste0("http://example.com/", "iris#")
#
# rdf %>%
# rdf_add(subject = paste0(base, "obs1"),
# predicate = paste0(base, "Sepal.Length"),
# object = 5.1)
#
# rdf
## -----------------------------------------------------------------------------
# rdf <- rdf()
# rdf %>% rdf_add("",
# "iris:Sepal.Length",
# object = 5.1)
# rdf
## -----------------------------------------------------------------------------
# rdf_serialize(rdf, "rdf.nq", format = "nquads")
## -----------------------------------------------------------------------------
# doc <- system.file("extdata/example.rdf", package="redland")
# rdf <- rdf_parse(doc, format = "rdfxml")
# rdf
## -----------------------------------------------------------------------------
# options(rdf_print_format = "rdfxml")
# rdf
## -----------------------------------------------------------------------------
# options(rdf_print_format = "turtle")
# rdf
## -----------------------------------------------------------------------------
# options(rdf_print_format = "jsonld")
# rdf
## -----------------------------------------------------------------------------
# rdf_serialize(rdf, "example.json", "jsonld") %>%
# jsonld_compact(context = '{"@vocab": "http://purl.org/dc/elements/1.1/"}')
## -----------------------------------------------------------------------------
# ex <- system.file("extdata/person.json", package="rdflib")
# cat(readLines(ex), sep = "\n")
# #jsonld_compact(ex, "{}")
#
## -----------------------------------------------------------------------------
# options(rdf_print_format = "nquads")
# rdf <- rdf_parse(ex, "jsonld")
# rdf
## -----------------------------------------------------------------------------
# jsonld_flatten(ex, context = "https://schema.org/")
## -----------------------------------------------------------------------------
# jsonld_flatten(ex) %>%
# jsonld_frame('{"@type": "https://schema.org//Person"}') %>%
# jsonld_compact(context = "https://schema.org/")
## -----------------------------------------------------------------------------
# as_rdf.list <- function(x, context = "https://schema.org/"){
# if(length(x) == 1) x <- x[[1]]
# x[["@context"]] <- context
# json <- jsonlite::toJSON(x, pretty = TRUE, auto_unbox = TRUE, force = TRUE)
# rdflib::rdf_parse(json, "jsonld")
# }
## -----------------------------------------------------------------------------
# context <- list("https://schema.org/",
# list(schema = "https://schema.org//",
# given = "givenName",
# family = "familyName",
# title = "name",
# year = "datePublished",
# note = "softwareVersion",
# comment = "identifier",
# role = "https://www.loc.gov/marc/relators/relaterm.html"))
#
## -----------------------------------------------------------------------------
# options(rdf_print_format = "nquads") # go back to the default
#
#
# R <- citation("rdflib")
# rdf <- as_rdf.list(R, context)
# rdf
## -----------------------------------------------------------------------------
# #source(system.file("examples/as_rdf.R", package="rdflib"))
# source(system.file("examples/tidy_schema.R", package="rdflib"))
#
# ## Testing: Digest some data.frames into RDF and extract back
# cars <- mtcars %>% rownames_to_column("Model")
# x1 <- as_rdf(iris, NULL, "iris:")
# x2 <- as_rdf(cars, NULL, "mtcars:")
# rdf <- c(x1,x2)
## -----------------------------------------------------------------------------
# sparql <-
# 'SELECT ?Species ?Sepal_Length ?Sepal_Width ?Petal_Length ?Petal_Width
# WHERE {
# ?s <iris:Species> ?Species .
# ?s <iris:Sepal.Width> ?Sepal_Width .
# ?s <iris:Sepal.Length> ?Sepal_Length .
# ?s <iris:Petal.Length> ?Petal_Length .
# ?s <iris:Petal.Width> ?Petal_Width
# }'
#
# iris2 <- rdf_query(rdf, sparql)
## ----echo=FALSE---------------------------------------------------------------
# DT::datatable(iris2)
## -----------------------------------------------------------------------------
# sparql <- tidy_schema("Species", "Sepal.Length", "Sepal.Width", prefix = "iris")
#
# rdf_query(rdf, sparql)
## ----include=FALSE------------------------------------------------------------
# unlink("rdf.nq")
# unlink("example.json")
|
