如何将大量 igraph 组合成一个 igraph - R
How to combine a large list of igraphs into one igraph - R
我有一个大图需要过滤。过滤（子图）后，我得到了一个子图列表。我需要再次将所有这些子图组合成一个图。不知道怎么组合大列表（近百万子图）
> require(igraph)
> graph <- make_ring(7) #this is my original graph
> V(graph)$name <- c("A", "B", "C", "D", "E", "F", "G") #name of vertices
> V(graph)$att1 <- c(1,2,NA,1,2,3,NA) #some attribute
> selected_vertices <- V(graph)$name[which(V(graph)$att1 == 1)] #let's say i need to subgraph the graph to include only vertices with att1 == 1 (and their first order neighbours)
> subgraph_list <- make_ego_graph(graph, order=1, selected_vertices) #this creates a list of igraphs but I need one graph containing all the graphs
这失败了：
> subgraph <- induced_subgraph(graph, unlist(subgraph_list ))
Error in as.igraph.vs(graph, vids) :
(list) object cannot be coerced to type 'double'
我已经尝试过其他方法来对图进行自我子图化，但由于它是一个相当大的图，因此需要很长时间，并且运行良好且相对较快的一个函数是 make_ego_graph，它创建了一个列表.
我假设您想要这些图的并集：
do.call(union, subgraph_list)
好的，我找到了适合我的解决方案（速度非常快，不会让我的电脑崩溃）。
> #first convert the list of igrpahs to list of data.frames
> subgraph_list_df <- lapply(subgraph_list, as_data_frame)
> # then combine all the data.frames in the list into one data.frame
> subgraph_df <- do.call(rbind, subgraph_list_df)
> #then make a graph out of the one combined data.frame
> subgraph <- graph_from_data_frame(subgraph_df , directed = FALSE)
出于我的目的，我知道子图是孤立的（它们之间没有共享边）。但是如果它们是连接的，应该只做一个唯一的（subgraph_df）在转换为图形之前去除重复的边。
我有一个大图需要过滤。过滤（子图）后，我得到了一个子图列表。我需要再次将所有这些子图组合成一个图。不知道怎么组合大列表（近百万子图）
> require(igraph)
> graph <- make_ring(7) #this is my original graph
> V(graph)$name <- c("A", "B", "C", "D", "E", "F", "G") #name of vertices
> V(graph)$att1 <- c(1,2,NA,1,2,3,NA) #some attribute
> selected_vertices <- V(graph)$name[which(V(graph)$att1 == 1)] #let's say i need to subgraph the graph to include only vertices with att1 == 1 (and their first order neighbours)
> subgraph_list <- make_ego_graph(graph, order=1, selected_vertices) #this creates a list of igraphs but I need one graph containing all the graphs
这失败了：
> subgraph <- induced_subgraph(graph, unlist(subgraph_list ))
Error in as.igraph.vs(graph, vids) :
(list) object cannot be coerced to type 'double'
我已经尝试过其他方法来对图进行自我子图化，但由于它是一个相当大的图，因此需要很长时间，并且运行良好且相对较快的一个函数是 make_ego_graph，它创建了一个列表.
我假设您想要这些图的并集：
do.call(union, subgraph_list)
好的，我找到了适合我的解决方案（速度非常快，不会让我的电脑崩溃）。
> #first convert the list of igrpahs to list of data.frames
> subgraph_list_df <- lapply(subgraph_list, as_data_frame)
> # then combine all the data.frames in the list into one data.frame
> subgraph_df <- do.call(rbind, subgraph_list_df)
> #then make a graph out of the one combined data.frame
> subgraph <- graph_from_data_frame(subgraph_df , directed = FALSE)
出于我的目的，我知道子图是孤立的（它们之间没有共享边）。但是如果它们是连接的，应该只做一个唯一的（subgraph_df）在转换为图形之前去除重复的边。