Merge branch 'master' of https://github.com/melvidoni/rsppfp

R/igraph.R

@@ -47,9 +47,19 @@ get_shortest_path <- function(g, origin, dest) {
   g.i <- graph_from_data_frame(g)
 
   # Get all the shortest paths to each node
-  sp <- shortest_paths(g.i, from = origin, to = get_all_nodes(gStar, dest), weights = E(g.i)$weight, output = "both")
+  sp <- shortest_paths(g.i, from = origin, to = get_all_nodes(g, dest), weights = E(g.i)$weight, output = "both")
 
-  # Return the shortest path
-  sp$vpath[which.min( lapply(sp$epath, function(y) 
-      ifelse(length(y) != 0, sum(E(g.i)$weight[ y[[1]] ]), 999999999)) )] [[1]]
+  # If there are no path, return NA
+  if(length(sp$vpath) == 1 & length(sp$vpath[[1]]) == 0)
+    return(NA)
+  # Otherwise...
+  else {
+    # Return the shortest path
+    sp$vpath[which.min( 
+      foreach(i = 1:length(sp$epath), .combine = c) %do% { 
+        ifelse( length(sp$epath[i]), sum(E(g.i)$weight[ sp$epath[[i]] ]), 999999999) 
+      } 
+    )]
+  }
+
 }

R/parsers.R

@@ -123,7 +123,7 @@ direct_graph <- function(graph, cores = 1L) {
 #'
 #' @family Parsers
 #'
-#' @param gStar A graph in data frame format, translated using one of the available functions.
+#' @param g A graph in data frame format, translated using one of the available functions.
 #' @param originalNode The name of the original node from G, that needs to be searched within G*. It is preferable
 #'    to use a character format, but this can also be of any simple type. No lists or vectors are allowed.
 #'
@@ -144,9 +144,9 @@ direct_graph <- function(graph, cores = 1L) {
 #' get_all_nodes(gStar, "v")                                                   
 #'
 #'
-get_all_nodes <- function(gStar, originalNode) {
+get_all_nodes <- function(g, originalNode) {
   # Get the list of nodes
-  nodes <- unique(c(gStar$from, gStar$to))
+  nodes <- unique(c(g$from, g$to))
 
   # Get all the nodes that end on that original node
   nodes[sapply(paste0("*\\s|", originalNode, "$"), function(y) grepl(y, nodes))]

vignettes/igraph.Rmd

@@ -97,25 +97,26 @@ get_shortest_path <- function(g, origin, dest) {
   g.i <- graph_from_data_frame(g)
   
   # Get all the shortest paths to each node
-  sp <- shortest_paths(g.i, from = origin, to = get_all_nodes(gStar, dest), weights = E(g.i)$weight, output = "both")
+  sp <- shortest_paths(g.i, from = origin, to = get_all_nodes(g, dest), weights = E(g.i)$weight, output = "both")
   
   # Return the shortest path
-  sp$vpath[which.min( lapply(sp$epath, function(y) 
-      ifelse(length(y) != 0, sum(E(g.i)$weight[ y[[1]] ]), 999999999)) )] [[1]]
+  sp$vpath[which.min( 
+    foreach(i = 1:length(sp$epath), .combine = c) %do% { 
+      ifelse( length(sp$epath[i]), sum(E(g.i)$weight[ sp$epath[[i]] ]), 999999999) 
+    } 
+  )]
 }
 ```
 
 And it can be used as in the following example:
 
 ```{r, warning=FALSE}
 # Obtain the shortest path using the simplified function
-shortestPath <- get_shortest_path(gStar, "u", "w")
+shortestPath <- get_shortest_path(gStar, "u", "t")
 shortestPath
 ```
 
-Also, 
-
-It is worth pointing out that a path can only be translated if it is presented as a list or vector of nodes, written sequentially. In iGraph, this is known as `vpaths` (vertexes paths).
+Also, it is worth pointing out that a path can only be translated if it is presented as a list or vector of nodes, written sequentially. In iGraph, this is known as `vpaths` (vertexes paths).
 
 ```{r}
 # Translate the vpath