adjacency-matrix

问题 Currently am developing a program that solves (if possible) any given labyrinth of dimensions from 3X4 to 26x30. I represent the graph using both adj matrix (sparse) and adj list. I would like to know how to output the total time taken by the DFS to find the solution using one and then the other method. Programatically, how could i produce such benchmark? 回答1: An useful table to work out with various graphs implementations: OPERATION EDGE LIST ADJ LIST ADJ MATRIX degree(v) O(m) O(d(v)) O(n)

问题 Edit: huge thanks to the users below for great contributions and to Gregor for benchmarking. Say I have a matrix filled with integer values like this... mat <- matrix(1:100, 10, 10) I can create a list of x, y coordinates of each element like this... addresses <- expand.grid(x = 1:10, y = 1:10) Now for each of these coordinates (i.e. for each element in mat) i would like to find the neighboring elements (including diagonals this should make 8 neighbors). I'm sure there is an easy way, can

问题 Hello I understand the concepts of adjacency list and matrix but I am confused as to how to implement them in Python: An algorithm to achieve the following two examples achieve but without knowing the input from the start as they hard code it in their examples: For adjacency list: a, b, c, d, e, f, g, h = range(8) N = [ {b:2, c:1, d:3, e:9, f:4}, # a {c:4, e:3}, # b {d:8}, # c {e:7}, # d {f:5}, # e {c:2, g:2, h:2}, # f {f:1, h:6}, # g {f:9, g:8} # h ] For adjacency matrix: a, b, c, d, e, f, g

问题 I have a matrix 2000x5 , in the first column the point number, and in columns 2-5 the 4 neighbours (0s if there isnt a neighbour). Is there an efficient way to create an adjacency matrix out of this ? 1 129 0 65 0 2 130 0 66 85 3 131 169 67 0 4 132 170 68 87 5 133 0 69 81 6 134 0 70 82 7 135 173 71 83 8 136 174 72 84 9 137 161 73 0 10 138 162 74 93 11 139 163 75 0 12 140 164 76 95 13 141 165 77 89 14 142 166 78 90 15 143 167 79 91 16 144 168 80 92 17 145 0 81 65 18 146 0 82 66 .... I found

问题 I want to make my matrix symmetric with regard to the row names and columns names, for example, I have a matrix > ma a b c d a 1 5 9 13 c 9 10 11 15 b 5 6 10 14 d 13 14 15 16 I want to make it like > ma a b c d a 1 5 9 13 b 5 6 10 14 c 9 10 11 15 d 13 14 15 16 Which means the matrix is symmetric in terms of row.names and column names are equal, so as the matrix is symmetric as well (actually I am working on adjacency matrix, thus it is rather important for adjacency matrix to be symmetric.

问题 is it possible to save an adjacency matrix after "get.adjacency()" as an adjacency matrix in R? I tried test <- get.adjacency(network) but I´m getting the error Error in View : cannot coerce class "structure("dgCMatrix", package = "Matrix")" to a data.frame. I´m using RStudio and the package iGraph. 回答1: Try using sparse=FALSE in the call to get.adjacency(...) g <- graph.full(5) test <- get.adjacency(g) class(test) # [1] "dgCMatrix" # attr(,"package") # [1] "Matrix" test <- get.adjacency(g

问题 I have this struct : struct graph { int** adj; /**< Adjacency matrix. */ int n; /**< Number of nodes in graph. */ }; and I have to create a void graph into this function: struct graph *graph_create(int nodes) { //To implement } How can I create a matrix using that double pointer int** adj ? 回答1: Here is the way to define a matrix with malloc() that i catch from GeeksForGeeks with some edition. 2D integer Matrix with int ** and malloc() int r = 3, c = 4, i, j, count; //arr[r][c] int **arr =

问题 This is my graphNEL object >mergedPathways_d A graphNEL graph with undirected edges Number of Nodes = 41 Number of Edges = 102 I have tried coerce . It did not work out. It asks to pre-define the matrix and To and From didnot work correctly, I had NA as entries in my adj matrix I tried using edgeL . It did not work out. The edge list I got had numbers as edges and not the names of the genes. And I don't know how to map genes onto those numbers. I tried converting it into igraph using igraph

问题 How can I combine these two functions to create a program that will allow a user to enter the count of vertices and then enter the graph edges? #include <iostream> using namespace std; int **malloc2d(int r, int c) { int **t = new int*[r]; for(int i = 0; i < r; i++) t[i] = new int[c]; return t; } int main() { int i; int j; int adj[V][V]; for(i = 0; i < V; i++) for(j = 0 ; j < V; j++) adj[i][j] = 0; for(i = 0; i < V; i++) adj[i][i]= 1; while (cin>> i >> j) { adj[i][j] = 1; adj[j][i] = 1; }

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 6 years ago . I have data frame like this: V1 V2 LABEL 1 83965 891552 A 2 88599 891552 B 3 42966 891552 C 4 83965 891553 D 5 88599 891553 D 6 42966 891553 B How can I convert it to something like adjacency matrix, but on the intersection of colum-row i would like to have, the third colum value, like that: 891552 891553 42966