read_network(): Consistency of node coordinates.

- Test

- Stop also at different nodes sharing the same coordinates (may be a typo)

DESCRIPTION

 Package: mapMCDA
 Title: Produce an epidemiological risk map by weighting multiple risk
         factors
-Version: 0.4.49
+Version: 0.4.50
 Date: 2020-04-29
 Authors@R: c( person("Andrea", "Apolloni", email =
         "andrea.apolloni@cirad.fr", role = c("ctb"), comment = "Animal

R/network.R

@@ -168,12 +168,33 @@ must be respected:",
   v_coord <- v_coord[order(v_coord$Node),]
   v_coord$Node <- as.factor(v_coord$Node)
   
-  ## Check consistency of coordinates
+  ## Check consistency of node coordinates
+  ## Each node has consistent coordinates
   if (any((idx <- table(v_coord$Node)) > 1)) {
     idx.nodes <- paste(names(idx)[idx > 1], collapse = ", ")
     stop("Inconsistent coordinates.\n",
          "The file specifies different coordinates in different lines for node(s): ", idx.nodes)
   }
+  ## Each coordinates represent a single node
+  if ( any(idx <- duplicated(v_coord[, -1])) ) {
+    
+    ## Return the nodes in dat (first col) matching a given set of coords x.
+    matching_coords <- function(x, dat) {
+      vapply(seq_len(nrow(dat)), function(i) all(dat[i, -1] == x), TRUE)
+    }
+    
+    iso_nodes <- 
+      lapply(
+        which(idx),
+        function(x) as.character(v_coord[matching_coords(v_coord[x, -1], v_coord), 1])
+      )
+    
+    stop("Detected different locations with the same coordinates.\n",
+         "This can be due to typos in location names.\n",
+         "Verify the coordinates of nodes ", 
+         paste(lapply(iso_nodes, paste, collapse = ", "), collapse = " and "),
+         ".")
+  }
   
   ans <- geonetwork::geonetwork(e_list, v_coord, directed = TRUE)
   

tests/testthat/test-load.R

@@ -93,6 +93,50 @@ test_that("Informative errors for incorrectly formatted network data", {
   )
 })
 
+test_that("Informative errors for inconsistent network data", {
+  
+  ## Same locations with different coordinates
+  df <- data.frame(
+    orig = LETTERS[c(1, 1)],
+    dest = letters[1:2],
+    olon = rep(1:2),
+    olat = rep(1:2),
+    dlon = rep(2:1),
+    dlat = rep(2:1),
+    vol = 10*1:2,
+    stringsAsFactors = FALSE
+  )
+  
+  tf <- tempfile(fileext = ".csv")
+  write.csv(df, file = tf, row.names = FALSE)
+  expect_error(
+    read_network(tf),
+    "Inconsistent coordinates"
+  )
+  
+  
+  ## Same coordinates with different location names
+  ## (typos in the names?)
+  df <- data.frame(
+    orig = LETTERS[1:2],
+    dest = letters[1:2],
+    olon = rep(1:2),
+    olat = rep(1:2),
+    dlon = rep(2:3),
+    dlat = rep(2:3),
+    vol = 10*1:2,
+    stringsAsFactors = FALSE
+  )
+  
+  tf <- tempfile(fileext = ".csv")
+  write.csv(df, file = tf, row.names = FALSE)
+  expect_error(
+    read_network(tf),
+    "Detected different locations with the same coordinates."
+  )
+  
+})
+
 test_that("read_network aggregates volume for multiple links", {
   
   base_df <- data.frame(