XML file not being extracted in R - r

Question

I am working on a project that requires me to go through various pages of links, and within these links find the xml file and parse it. I am having trouble extracting the xml file. There are two xml files within each link and I am interested in the one that is bigger. How can I extract the xml file, and find the the one with the max size. I tried using the grep function but its constantly giving me an error.
sotu<-data.frame()
for (i in seq(1,501, 100))
{
securl <- paste0("https://www.sec.gov/cgi-bin/srch-edgar?text=abs-
ee&start=", i, "&count=100&first=2016")
main.page <- read_html(securl)
urls <- main.page %>%
html_nodes("div td:nth-child(2) a")%>%
html_attr("href")
baseurl <- "https://www.sec.gov"
fulllink <-paste(baseurl, urls, sep = "")
names <- main.page %>%
html_nodes ("div td:nth-child(2) a") %>%
html_text()
date <- main.page %>%
html_nodes ("td:nth-child(5)") %>%
html_text()
result <- data.frame(urls=fulllink,companyname=names,FilingDate=date, stringsAsFactors = FALSE)
sotu<- rbind(sotu,result)
}
for (i in seq(nrow(sotu)))
{
getXML <- read_html(sotu$urls[1]) %>%
grep("xml", getXML, ignore.case=FALSE )
}
Everything works except when I try to loop over every link and find the xml file, I keep getting an error. Is this not the right function?

Answer 1

With some help from dplyr we can do:
sotu %>%
rowwise() %>%
do({
read_html(.$urls) %>%
html_table() %>%
as.data.frame() %>%
filter(grepl('.*\\.xml', Document)) %>%
filter(Size == max(Size))
})
or, as the type is always 'EX-102' at least in the example:
sotu %>%
rowwise() %>%
do({
read_html(.$urls) %>%
html_table() %>%
as.data.frame() %>%
filter(Type == 'EX-102')
})
This also get rid of the for loop, which is rarely a good idea in R.