scraping zappa wikipedia page

Loading lots of packages

The following is loading necessary packages.

library(rvest)
library(xml2)
library(tidyr)
library(dplyr)
library(tibble)

## Warning: le package 'tibble' a été compilé avec la version R 3.5.3

library(purrr)

library(ggplot2)

library(tidygraph)
library(ggraph)
library(igraph)

library(ggiraph)
library(flextable)
table_head <- function(x){
  ft <- regulartable(head(x))
  autofit(ft)
}

Scrapping the data

List of Frank Zappa performers

We will scrap a list of performers from wikipedia page here.

Frank Zappa performers wikipedia page

performers <- read_html('https://en.wikipedia.org/wiki/List_of_performers_on_Frank_Zappa_records') %>%
  html_nodes('#mw-content-text > div > table.wikitable') %>% 
  map_df( html_table ) %>% 
  as_tibble()
table_head(performers) 

Name	Year(s)	Appeared on	Instrument
Murray Adler	1978, 1996	Studio Tan, Läther	Violin
Phyllis Altenhaus	1987	Uncle Meat	Voice
Mike Altschul	1972, 1978–1981, 1996, 2004, 2007, 2008	Waka/Jawaka, The Grand Wazoo, Studio Tan, Orchestral Favorites, Tinseltown Rebellion, Läther, QuAUDIOPHILIAc, Wazoo, One Shot Deal	Woodwinds
Jay Anderson	1983–1985	The Man from Utopia, Thing-Fish, Cruising with Ruben & the Jets (1985 Remix)	Bass
Peter Arcaro	1962, 1996	The Lost Episodes	Trumpet, Conductor
Harold Ayres	1968	Lumpy Gravy	Violin

Frank Zappa discography

And few details about the discography here. We are only considering live and studio albums.

Frank Zappa discography wikipedia page

discography <- read_html("https://en.wikipedia.org/wiki/Frank_Zappa_discography") %>%
  html_node('#mw-content-text > div > table.wikitable')
xml_remove( discography %>% xml_child("tbody/tr") )

discography <- html_table(discography, fill = TRUE)
discography <- discography[, c(2, 4)] %>% 
  set_names(c("year", "album")) %>% 
  filter(!grepl("on Stage", album))
table_head(discography)

year	album
1966	Freak Out! (with The Mothers of Invention)
1967	Absolutely Free (with The Mothers of Invention)
1967	Lumpy Gravy (with Abnuceals Emuukha Electric Symphony Orchestra)
1968	We're Only in It for the Money (with The Mothers of Invention)
1968	Cruising with Ruben & the Jets (with The Mothers of Invention)
1969	Mothermania (with The Mothers of Invention)

Clean our data

There are few annoying data corrections to make the analysis easier later:

• clean album names when there is a comma - the comma will be used to separate album name later.
• change few album names when two or more spelling are used
• drop some specific strings

# manual cleaning ----

clean_album_name <- function(data){
  data$album <- gsub(", Vol.", "- Volume", data$album )
  data$album <- gsub("Civilization, ", "Civilization - ", data$album )
  data$album <- gsub("Overnight", "Over-Nite", data$album )
  data$album <- gsub(" \\(\'\\)", "", data$album )
  data$album <- gsub("\\[1\\]", "", data$album )
  data
}

performers <- rename(performers, musician = "Name", years = `Year(s)`, album = `Appeared on`)

performers <- clean_album_name(performers) %>% 
  select(album, musician ) %>% 
  separate_rows(album, sep = ", ")
discography <- clean_album_name(discography)
table_head(discography)

First explorations

We can already perform few quick analysis, i.e.:

how much album have been released each years

count(discography, year) %>% 
  ggplot(aes(year, n)) + geom_col()

How many musicians are in each albums?

We are using a semi_join to subset our album list.

performers <- performers %>% 
  semi_join(discography, by = "album")
table_head(performers) 

Frank Zappa was often collaborating with 10 musicians at least per album.

count(performers, album) %>% 
  ggplot(aes(album, n)) + geom_point() + 
  geom_segment(aes(xend = album, yend = 0)) + 
  theme(axis.text.x = element_text(angle = 90, hjust = 1))

musician_entities <- performers %>%
  transmute(name=musician, entity="musician") %>%
  distinct()

album_entities <- performers %>%
  left_join(discography, by = "album") %>%
  transmute(name=album, entity="album") %>%
  distinct()
  

entities <- bind_rows(musician_entities, album_entities) %>% 
  mutate(id = seq_along(entity))

edges <- entities %>% 
  filter(entity %in% "album") %>% 
  select(-entity) %>% rename(to = id, album = name) %>% 
  right_join(performers, by = c("album" = "album"))

edges <- entities %>%
  filter(entity %in% "musician") %>%
  select(-entity) %>% rename(from = id, musician = name) %>%
  right_join(edges, by = c("musician" = "musician"))

edges <- edges %>% select(from, to, musician, album)

entities_df <- entities %>% 
  select(id, name, entity) %>% 
  rename(type=entity) 

net <- graph_from_data_frame(d=edges, vertices=entities_df, directed=T) 

ggraph(net) +
    geom_edge_fan(alpha = .8, edge_width = 0.2, edge_colour= "gray") +
    geom_point(aes(x, y, fill = type ), colour="black", stroke = 1, shape = 21, size = 4 ) +
    theme_graph(background="#FFFFFF") + theme(legend.position = "none") +
    scale_fill_manual(values = c("album" = "black", "musician" = "#006699")) + 
    scale_alpha_continuous(range = c(0.4, 0.75))

## Using `nicely` as default layout