Internal-PageRank-Calculation-2.r

library(igraph)
library(dplyr)
library(ggplot2)
library(magrittr)
#library(ForceAtlas2)

file_outlinks <- 'C:/Users/evgeniy/Downloads/all_outlinks.csv'
website_url <- 'https//www.flyeralarm.com'

# transform raw internal page rank to page rank
map <- function(x, range = c(0,1), from.range=NA) {
 if(any(is.na(from.range))) from.range <- range(x, na.rm=TRUE)
 
 ## check if all values are the same
 if(!diff(from.range)) return(
 matrix(mean(range), ncol=ncol(x), nrow=nrow(x), 
 dimnames = dimnames(x)))
 
 ## map to [0,1]
 x <- (x-from.range[1])
 x <- x/diff(from.range)
 ## handle single values
 if(diff(from.range) == 0) x <- 0 
 
 ## map from [0,1] to [range]
 if (range[1]>range[2]) x <- 1-x
 x <- x*(abs(diff(range))) + min(range)
 
 x[x<min(range) | x>max(range)] <- NA
 
 x
}

 DF <- read.csv2(file_outlinks, header=TRUE, sep = ",", stringsAsFactors = F, skip=1 )
 ## we keep only link
 DF <- filter(DF,grepl(website_url,Source) & Type=="HREF" & Follow=="true") %>%
 select(Source,Destination)
 
 DF <- as.data.frame(sapply(DF,gsub,pattern=website_url,replacement=""))
 
 ## adapt colnames and rownames
 colnames(DF) <- c("Source","Destination")
 rownames(DF) <- NULL

# generate graph with data.frame
graphObject = graph.data.frame(DF)

# calculate pagerank
urls_pagerank <- page.rank(graphObject, directed= TRUE, damping = 0.85) %>%
 use_series("vector") %>%
 sort(decreasing = TRUE) %>%
 as.data.frame %>%
 set_colnames("raw.internal.pagerank")

urls_pagerank$Address<-rownames(urls_pagerank)
rownames(urls_pagerank) <- NULL

urls_pagerank <- mutate(urls_pagerank, internal.pagerank = map(raw.internal.pagerank, c(1,10)))