Update spatial network funs - load sf if needed

R/SpatialLinesNetwork.R

@@ -86,9 +86,9 @@ setClass("sfNetwork", representation(sl = "sf",
 #' plot(shortpath, col = "red", lwd = 4, add = TRUE)
 #' library(sf)
 #' SLN_sf <- SpatialLinesNetwork(route_network_sf)
-#' plot(SLN_sf@sl$geometry)
-#' # shortpath <- sum_network_routes(SLN_sf, 1, 50, sumvars = "length")
-#' # plot(shortpath, col = "red", lwd = 4, add = TRUE)
+#' plot(SLN_sf)
+#' shortpath <- sum_network_routes(SLN_sf, 1, 50, sumvars = "length")
+#' plot(shortpath$geometry, col = "red", lwd = 4, add = TRUE)
 SpatialLinesNetwork <- function(sl, uselonglat = FALSE, tolerance = 0.000) {
   UseMethod("SpatialLinesNetwork")
 }
@@ -120,10 +120,6 @@ SpatialLinesNetwork.Spatial <- function(sl, uselonglat = FALSE, tolerance = 0.00
 #' @export
 SpatialLinesNetwork.sf <-function(sl, uselonglat = FALSE, tolerance = 0.000) {
 
-  if ("sf" %in% (.packages()) == FALSE) {
-    stop("sf package must be loaded first. Run library(sf)")
-  }
-
   nodecoords <- as.data.frame(sf::st_coordinates(sl)) %>%
     dplyr::group_by(.data$L1) %>%
     dplyr::mutate(nrow = n(), rownum = 1:n()) %>%
@@ -165,10 +161,9 @@ SpatialLinesNetwork.sf <-function(sl, uselonglat = FALSE, tolerance = 0.000) {
 #' representation.
 #' @param ... Arguments to pass to relevant plot function.
 #' @examples
-#' data(routes_fast)
-#' rnet <- overline(routes_fast, attrib = "length")
-#' SLN <- SpatialLinesNetwork(rnet)
+#' SLN <- SpatialLinesNetwork(route_network)
 #' plot(SLN)
+#' plot(SLN, component = "graph")
 #' @export
 setMethod("plot", signature = c(x="SpatialLinesNetwork"),
           definition = function(x, component = "sl", ...){
@@ -183,23 +178,21 @@ setMethod("plot", signature = c(x="SpatialLinesNetwork"),
             }
           })
 
-#' Plot a sfNetwork
+#' Plot an sfNetwork
 #'
 #' @param x The sfNetwork to plot
 #' @param component The component of the network to plot. Valid values are "sl"
 #' for the geographic (sf) representation or "graph" for the graph
 #' representation.
 #' @param ... Arguments to pass to relevant plot function.
 #' @examples
-#' data(routes_fast)
-#' rnet <- overline(routes_fast, attrib = "length")
-#' SLN <- SpatialLinesNetwork(rnet)
-#' plot(SLN)
+#' SLN_sf <- SpatialLinesNetwork(route_network_sf)
+#' plot(SLN_sf)
 #' @export
 setMethod("plot", signature = c(x="sfNetwork"),
           definition = function(x, component = "sl", ...){
             if (component == "sl") {
-              sp::plot(x@sl, ...)
+              sp::plot(x@sl$geometry, ...)
             }
             else if (component == "graph") {
               igraph::plot.igraph(x@g, ...)
@@ -482,16 +475,16 @@ sum_network_routes <- function(sln, start, end, sumvars, combinations = FALSE) {
   if (length(start) != length(end) && combinations == FALSE) {
     stop("start and end not the same length.")
   }
-  if (is(sln, "sfNetwork") & "sf" %in% (.packages()) == FALSE) {
-    stop("sf package must be loaded first. Run library(sf)")
-  }
 
   if (combinations == FALSE) {
     routesegs <- lapply(1:length(start), function(i) {
         unlist(igraph::get.shortest.paths(sln@g, start[i], end[i], output="epath")$epath)
       })
 
     if (is(sln, "sfNetwork")) {
+      if (is(sln, "sfNetwork") & "sf" %in% (.packages()) == FALSE) {
+        stop("Load the sf package, e.g. with\nlibrary(sf)")
+        }
       routecoords <- mapply(function(routesegs, start) {
         linecoords <- sf::st_coordinates(sln@sl[routesegs,])
         linecoords <- lapply(1:max(linecoords[,'L1']), function(x){