setwd("...") #insert your work directory

library ("igraph") #for network analysis

# Load matrix from csv 
M = as.matrix(read.csv(file.choose(), sep = ";", header = T, row.names = 1))

#Transform into an unweighted, directed, twomode igraph object (optional, only for unweighted analysis), otherwise jump to #multiply the transposes... and proceed with M instead of M2
two_mode_network <- graph.incidence(M, directed = TRUE, mode = "out", weighted = NULL)

# Delete isolates from the twomode network (optional)
Isolated <- which(degree(two_mode_network)==0)
two_mode_network_ni <- delete.vertices(two_mode_network, Isolated)
class(two_mode_network_ni)

# Transform twomode back to an incidence matrix (optional)
M2 <- as_incidence_matrix(two_mode_network_ni, names = TRUE)

# multiply the transpose of M by M -> create a onemode network of concepts
om_concept_actor <- t(M2)%*%(M2)

# multiply M by the transpose of M -> create a onemode network of actors
om_actor_concept <- (M2)%*%t(M2)

# set diagonals to zero
diag(om_actor_concept)<-0
diag(om_concept_actor)<-0

write.table (om_concept_actor, file ="om_concept_nonorm.csv", dec = ".", sep = ";", col.names = NA)
write.table (om_actor_concept, file = "om_actor_nonorm.csv", dec = ".", sep = ";", col.names = NA)
write.table (M2, file = "tm_unweighted.csv", dec = ".", sep = ";", col.names = NA)