## ----echo = TRUE, eval = FALSE------------------------------------------------ # install.packages("igraph") ## ----echo = FALSE------------------------------------------------------------- knitr::opts_chunk$set(fig.width = 6, fig.height = 6) ## ----setup-------------------------------------------------------------------- library("igraph") ## ----------------------------------------------------------------------------- g <- make_empty_graph() ## ----------------------------------------------------------------------------- g <- make_graph(edges = c(1, 2, 1, 5), n = 10, directed = FALSE) ## ----echo = TRUE-------------------------------------------------------------- g <- make_graph(~ 1--2, 1--5, 3, 4, 5, 6, 7, 8, 9, 10) ## ----echo = TRUE-------------------------------------------------------------- g ## ----echo = TRUE-------------------------------------------------------------- summary(g) ## ----echo = TRUE-------------------------------------------------------------- g <- make_graph("Zachary") ## ----------------------------------------------------------------------------- plot(g) ## ----------------------------------------------------------------------------- g <- add_vertices(g, 3) ## ----------------------------------------------------------------------------- g <- add_edges(g, edges = c(1, 35, 1, 36, 34, 37)) ## ----echo = TRUE, eval=FALSE-------------------------------------------------- # g <- g + edges(c(1, 35, 1, 36, 34, 37)) ## ----echo = TRUE, error = TRUE------------------------------------------------ g <- add_edges(g, edges = c(38, 37)) ## ----echo = TRUE-------------------------------------------------------------- g <- g %>% add_edges(edges = c(1, 34)) %>% add_vertices(3) %>% add_edges(edges = c(38, 39, 39, 40, 40, 38, 40, 37)) g ## ----echo = TRUE-------------------------------------------------------------- edge_id_to_delete <- get_edge_ids(g, c(1, 34)) edge_id_to_delete ## ----------------------------------------------------------------------------- g <- delete_edges(g, edge_id_to_delete) ## ----echo = TRUE-------------------------------------------------------------- g <- make_ring(10) %>% delete_edges("10|1") plot(g) ## ----echo = TRUE-------------------------------------------------------------- g <- make_ring(5) g <- delete_edges(g, get_edge_ids(g, c(1, 5, 4, 5))) plot(g) ## ----------------------------------------------------------------------------- g1 <- graph_from_literal( A - B:C:I, B - A:C:D, C - A:B:E:H, D - B:E:F, E - C:D:F:H, F - D:E:G, G - F:H, H - C:E:G:I, I - A:H ) plot(g1) ## ----echo = TRUE-------------------------------------------------------------- is_chordal(g1, fillin = TRUE) ## ----echo = TRUE-------------------------------------------------------------- chordal_graph <- add_edges(g1, is_chordal(g1, fillin = TRUE)$fillin) plot(chordal_graph) ## ----echo = TRUE-------------------------------------------------------------- graph1 <- make_tree(127, 2, mode = "undirected") summary(graph1) ## ----------------------------------------------------------------------------- graph2 <- make_tree(127, 2, mode = "undirected") ## ----echo = TRUE-------------------------------------------------------------- identical_graphs(graph1, graph2) ## ----echo = TRUE-------------------------------------------------------------- graph1 <- sample_grg(100, 0.2) summary(graph1) ## ----echo = TRUE-------------------------------------------------------------- graph2 <- sample_grg(100, 0.2) identical_graphs(graph1, graph2) ## ----echo = TRUE-------------------------------------------------------------- isomorphic(graph1, graph2) ## ----------------------------------------------------------------------------- g <- make_graph( ~ Alice - Boris:Himari:Moshe, Himari - Alice:Nang:Moshe:Samira, Ibrahim - Nang:Moshe, Nang - Samira ) ## ----echo = TRUE-------------------------------------------------------------- V(g)$age <- c(25, 31, 18, 23, 47, 22, 50) V(g)$gender <- c("f", "m", "f", "m", "m", "f", "m") E(g)$is_formal <- c(FALSE, FALSE, TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, FALSE) summary(g) ## ----echo = TRUE, eval=FALSE-------------------------------------------------- # g <- make_graph( # ~ Alice - Boris:Himari:Moshe, Himari - Alice:Nang:Moshe:Samira, # Ibrahim - Nang:Moshe, Nang - Samira # ) %>% # set_vertex_attr("age", value = c(25, 31, 18, 23, 47, 22, 50)) %>% # set_vertex_attr("gender", value = c("f", "m", "f", "m", "m", "f", "m")) %>% # set_edge_attr("is_formal", value = c(FALSE, FALSE, TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, FALSE)) # summary(g) ## ----echo = TRUE-------------------------------------------------------------- E(g)$is_formal E(g)$is_formal[1] <- TRUE E(g)$is_formal ## ----echo = TRUE-------------------------------------------------------------- g$date <- c("2022-02-11") graph_attr(g, "date") ## ----echo = TRUE-------------------------------------------------------------- match(c("Ibrahim"), V(g)$name) ## ----echo = TRUE-------------------------------------------------------------- V(g)$name[1:3] <- c("Alejandra", "Bruno", "Carmina") V(g) ## ----echo = TRUE-------------------------------------------------------------- g <- delete_vertex_attr(g, "gender") V(g)$gender ## ----echo = TRUE-------------------------------------------------------------- degree(g) ## ----echo = TRUE-------------------------------------------------------------- degree(g, 7) ## ----echo = TRUE-------------------------------------------------------------- degree(g, v = c(3, 4, 5)) ## ----echo = TRUE-------------------------------------------------------------- degree(g, v = c("Carmina", "Moshe", "Nang")) ## ----echo = TRUE-------------------------------------------------------------- degree(g, "Bruno") ## ----echo = TRUE-------------------------------------------------------------- edge_betweenness(g) ## ----echo = TRUE-------------------------------------------------------------- ebs <- edge_betweenness(g) as_edgelist(g)[ebs == max(ebs), ] ## ----echo = TRUE-------------------------------------------------------------- which.max(degree(g)) ## ----echo = TRUE-------------------------------------------------------------- graph <- graph.full(n = 10) only_odd_vertices <- which(V(graph) %% 2 == 1) length(only_odd_vertices) ## ----echo = TRUE-------------------------------------------------------------- seq <- V(graph)[2, 3, 7] seq ## ----echo = TRUE-------------------------------------------------------------- seq <- seq[1, 3] # filtering an existing vertex set seq ## ----echo = TRUE, eval = FALSE------------------------------------------------ # seq <- V(graph)[2, 3, 7, "foo", 3.5] # ## Error in simple_vs_index(x, ii, na_ok) : Unknown vertex selected ## ----echo = TRUE-------------------------------------------------------------- V(g)[age < 30]$name ## ----echo = TRUE-------------------------------------------------------------- `%notin%` <- Negate(`%in%`) ## ----echo = TRUE-------------------------------------------------------------- V(g)$degree <- c("A", "B", "B+", "A+", "C", "A", "B") V(g)$degree[degree(g) == 3] ## ----echo = TRUE-------------------------------------------------------------- V(g)$name[degree(g) == 3] ## ----echo = TRUE, warning = FALSE--------------------------------------------- E(g)[.from(3)] ## ----echo = TRUE, warning = FALSE--------------------------------------------- E(g)[.from("Carmina")] ## ----echo = TRUE-------------------------------------------------------------- E(g)[3:5 %--% 5:6] ## ----------------------------------------------------------------------------- V(g)$gender <- c("f", "m", "f", "m", "m", "f", "m") ## ----echo = TRUE-------------------------------------------------------------- men <- V(g)[gender == "m"]$name men ## ----echo = TRUE-------------------------------------------------------------- women <- V(g)[gender == "f"]$name women ## ----echo = TRUE-------------------------------------------------------------- E(g)[men %--% women] ## ----echo = TRUE-------------------------------------------------------------- as_adjacency_matrix(g) ## ----------------------------------------------------------------------------- layout <- layout_with_kk(g) ## ----------------------------------------------------------------------------- layout <- layout_as_tree(g, root = 2) ## ----------------------------------------------------------------------------- layout <- layout_with_kk(g) ## ----------------------------------------------------------------------------- plot(g, layout = layout, main = "Social network with the Kamada-Kawai layout algorithm") ## ----------------------------------------------------------------------------- plot( g, layout = layout_with_fr, main = "Social network with the Fruchterman-Reingold layout algorithm" ) ## ----------------------------------------------------------------------------- V(g)$color <- ifelse(V(g)$gender == "m", "yellow", "red") plot( g, layout = layout, vertex.label.dist = 3.5, main = "Social network - with genders as colors" ) ## ----------------------------------------------------------------------------- plot(g, layout = layout, vertex.label.dist = 3.5, vertex.color = as.factor(V(g)$gender)) ## ----------------------------------------------------------------------------- plot(g, layout = layout, vertex.label.dist = 3.5, vertex.size = 20, vertex.color = ifelse(V(g)$gender == "m", "yellow", "red"), edge.width = ifelse(E(g)$is_formal, 5, 1) ) ## ----session-info------------------------------------------------------------- sessionInfo()