# R igraph manual pages

Use this if you are using igraph from R

## Sample the hierarchical stochastic block model

### Description

Sampling from a hierarchical stochastic block model of networks.

### Usage

sample_hierarchical_sbm(n, m, rho, C, p)


### Arguments

 n Integer scalar, the number of vertices. m Integer scalar, the number of vertices per block. n / m must be integer. Alternatively, an integer vector of block sizes, if not all the blocks have equal sizes. rho Numeric vector, the fraction of vertices per cluster, within a block. Must sum up to 1, and rho * m must be integer for all elements of rho. Alternatively a list of rho vectors, one for each block, if they are not the same for all blocks. C A square, symmetric numeric matrix, the Bernoulli rates for the clusters within a block. Its size must mach the size of the rho vector. Alternatively, a list of square matrices, if the Bernoulli rates differ in different blocks. p Numeric scalar, the Bernoulli rate of connections between vertices in different blocks. ... Passed to sample_hierarchical_sbm.

### Details

The function generates a random graph according to the hierarchical stochastic block model.

An igraph graph.

### Author(s)

Gabor Csardi csardi.gabor@gmail.com

### See Also

sbm.game

### Examples


## Ten blocks with three clusters each
C <- matrix(c(1  , 3/4,   0,
3/4,   0, 3/4,
0  , 3/4, 3/4), nrow=3)
g <- sample_hierarchical_sbm(100, 10, rho=c(3, 3, 4)/10, C=C, p=1/20)
g
if (require(Matrix)) { image(g[]) }


[Package igraph version 1.2.3 Index]