#einhorn_13F_2016.R
# Holdings of D. Einhorns Hedge Fund
# Metadata / Background Info
#https://www.sec.gov/Archives/edgar/data/1079114/000107911416000025/xslForm13F_X01/primary_doc.xml
library(ggplot2)
library(rvest)
library(stringi)
library(purrr)
library(tidyr)
library(dplyr)

# data
# read in HTML:
html_url <- "https://www.sec.gov/Archives/edgar/data/1079114/000107911416000025/xslForm13F_X01/Greenlight_13FXML_06302016.xml"
html_dat <- read_html(html_url)

#find the right table in HTML DOM
html_dat <- html_table(html_dat, header = TRUE, fill=TRUE)[[4]]
glimpse(html_dat)

# parse messed-up table header
einhorn_col <- map2_chr(html_dat[1,],html_dat[2,], paste)
einhorn <- html_dat
colnames(einhorn) <-  make.names(stri_trim(stringi::stri_trans_tolower(paste0( einhorn_col, sep=""))))
einhorn <- einhorn[3:nrow(einhorn),]

# there are 2 important numeric columns
einhorn[, "value..x.1000."] <- as.numeric(gsub(",", "",einhorn[, "value..x.1000."]))
einhorn[, "shrs.or.prn.amt"] <- as.numeric(gsub(",", "", einhorn[, "shrs.or.prn.amt"]))

# most important holdings by value
einhorn %>%
        group_by(name.of.issuer) %>%
        summarise(sum_value=sum(value..x.1000.),sum_shares=sum(shrs.or.prn.amt)) %>%
        arrange(desc(sum_value))

# show some company names
companies <- unique(einhorn$name.of.issuer)
sample(companies, 6)

colnames(einhorn)
 [1] "name.of.issuer"          "title.of.class"          "cusip"
 [4] "value..x.1000."          "shrs.or.prn.amt"         "sh..prn"
 [7] "put..call"               "investment.discretion"   "other.manager"
[10] "voting.authority.sole"   "voting.authority.shared" "voting.authority.none"

company        CIK  SIC state state.inc FY.end            street.address             city.state
  1 GOOGLE INC. 0001288776 7370    CA        DE   1231 1600 AMPHITHEATRE PARKWAY MOUNTAIN VIEW CA 94043

sample(companies, 6)
[1] "TAKE-TWO INTERACTIVE SOFTWAR" "TERRAFORM PWR INC"
[3] "APPLE INC"                    "VOYA FINL INC"
[5] "AERCAP HOLDINGS NV"           "PERRIGO CO PLC

finreportr::CompanyInfo("TERRAFORM PWR INC")

Error in open.connection(x, "rb") : HTTP error 400.
Calls: <Anonymous> -> <Anonymous> -> read_html.default