Download data for each bottom node in the pxweb api
test_pxweb_api_get_data(nodes, nodesList, download_all = FALSE,
seed = as.integer(Sys.time()))
Nodes downloaded with test_pxweb_api_get_nodes
Node metadata downloaded with test_pxweb_api_get_node_metadata
Should all data be downloaded (TRUE) or sample (FALSE)
Seed to use if download_all is FALSE and a sample is downloaded
data.frame with information download_error
containing download errors