> library("nycflights13")
> library("lubridate")
> library("DiagrammeR")
>
> # Choose a day from 2013 for NYC flight data
> # (You can choose any Julian day, it's interesting to see results for different days)
> day_of_year <- 10
>
> # Get a data frame of complete cases (e.g., flights have departure and arrival times)
> nycflights13 <-
+   nycflights13::flights[which(complete.cases(nycflights13::flights) == TRUE), ]
>
> # Generate a POSIXct vector of dates using the 'ISOdatetime' function
> # Columns 1, 2, and 3 are year, month, and day columns
> # Column 4 is a 4-digit combination of hours (00-23) and minutes (00-59)
> date_time <-
+   data.frame("date_time" =
+                ISOdatetime(year = nycflights13[,1],
+                            month = nycflights13[,2],
+                            day = nycflights13[,3],
+                            hour = gsub("[0-9][0-9]$", "", nycflights13[,4]),
+                            min = gsub(".*([0-9][0-9])$", "\\1", nycflights13[,4]),
+                            sec = 0, tz = "GMT"))
>
> # Add the POSIXct vector 'date_time' to the 'nycflights13' data frame
> nycflights13 <- cbind(date_time, nycflights13)
>
> # Select flights only from the specified day of the year 2013
> nycflights13_day <-
+   subset(nycflights13,
+          date_time >= ymd('2013-01-01', tz = "GMT") + days(day_of_year - 1) &
+            date_time < ymd('2013-01-01', tz = "GMT") + days(day_of_year))
>
> # Create the 'nodes' data frame where at least one column is named "nodes" or "node_id"
> # Column 12 is the 3-letter code for the airport departing from
> # Column 13 is for the airport arriving to
> # (Option: change df to 'nycflights13_day' and only airports used for the day will be included)
> nodes_df <- create_nodes(nodes = unique(c(nycflights13[,12],
+                                           nycflights13[,13])),
+                          label = FALSE)
>
> # The 'edges' data frame must have columns named 'edge_from' and 'edge_to'
> # The color attribute is determined with an 'ifelse' statement, where
> # column 8 is the minutes early (negative values) or minutes late (positive values)
> # for the flight arrival
> edges_df <- create_edges(edge_from = nycflights13_day[,12],
+                          edge_to = nycflights13_day[,13],
+                          color = ifelse(nycflights13_day[,8] < 0,
+                                         "green", "red"))
>
> # Set the graph diagram's default attributes for...
>
> # ...nodes
> node_attrs <- c("style = filled", "fillcolor = lightblue",
+                 "color = gray", "shape = circle", "fontname = Helvetica",
+                 "width = 1")
>
> # ...edges
> edge_attrs <- c("arrowhead = dot")
>
> # ...and the graph itself
> graph_attrs <- c("layout = circo",
+                  "overlap = false",
+                  "fixedsize = true",
+                  "ranksep = 3",
+                  "outputorder = edgesfirst")
>
> # Generate the graph diagram in the RStudio Viewer.
> # The green lines show flights that weren't late (red indicates late arrivals)
> # This graph is for a single day of flights, airports that are unconnected on a
> # given day may be destinations on another day
> graphviz_graph(nodes_df = nodes_df, edges_df = edges_df,
+                graph_attrs = graph_attrs, node_attrs = node_attrs,
+                edge_attrs = edge_attrs, directed = TRUE) %>>%
+   graphviz_render(width = 1200, height = 800)
Error: could not find function "%>>%"