Rでコード進行を丁寧丁寧丁寧に可視化してみる（Level 1） ref: http://qiita.com/sasanquaneuf/items/aed57423b4edce26f783

arules.R

library(arulesSequences)
# 上述の試行錯誤の名残…arulesSequencesでarulesも入る
# scraping.Rの続きで

t <- song_data_all[,c("before","after")]
result <- apriori(as(t,"transactions"), parameter = list(support = 0.008, confidence = 0.05))

# さだまさし→0.01/0.05
# 小田和正→0.005/0.05
# いきものがかり→0.005/0.05
# 図を適当にきれいにするための適当な条件

e <- as(result,"data.frame")
e$LHS <- str_replace_all(e$rules,"=>.+","")
e$RHS <- str_replace_all(e$rules,".+=>","")

scraping.R

library(rvest)
library(stringr)

# さだまさし
dataids <- c("27407","980","2699","7814","13411","25116","7815","7816","13416","27404","25115","4531","7817",
             "7810","7812","13421","13615","13426","13413","13422","13602","25113","25114","27402","25577",
             "2956","2955","7820","7819","7813","7811","7809","7818","13429","13428","13601","13430","13425",
             "13423","13424","13420","13418","13419","13603","13412","13415","13417","13414","13607","13606",
             "13600","13427","13613","13616","13612","13609","13610","13604","13608","13605","13614","13611",
             "27406","23108","27405","21513","21512","25576","26542","27403","27738")

# 小田和正
dataids <- c("3333","2338","2281","2532","9724","9988","2531","9723","9719","9503","9505","9718","9992","9990",
             "9717","10002","9714","10174","21171","20450","21174","21177","21175","2600","9981","9716","9986",
             "10172","10000","9999","9506","9509","10001","9998","10003","9715","9997","9504","9980","9984",
             "9722","9993","9725","9991","9987","9507","9995","9996","9721","9508","9510","9720","9994","9982",
             "10173","9983","9985","9989","22640","21170","17228","21176","20451","21173","21172","22071","25201")

# いきものがかり
dataids <- c("953","1928","3980","5177","1367","956","950","1378","1406","1400","24172","1375","3729","3976","5422",
             "5515","5180","13809","2085","5186","1927","5188","18414","27742","5419","5528","5426","6272","24298",
             "5522","5529","6265","7808","5517","5190","5418","5420","6264","6268","6271","13929","13930","14819",
             "16566","22620","2678","3979","5524","5518","5178","5184","5185","5521","5416","5421","5525","6269",
             "8565","1925","1926","2087","2086","3977","3978","5526","5523","5520","5175","5176","5179","5181","5182",
             "5183","5187","5189","5516","5417","5423","5424","5425","5427","5519","5527","5530","5531","5532","6266",
             "6267","6270","8485","8566","13927","13928","19814","16567","19330","24134","21524","25365","23789",
             "21709","21961","21525","21523","24135","24133")

# サカナクション
dataids <- c("27032","4676","5075","1035","2117","5070","5073","5074","2658","4689","1187","5072","5076","6759",
             "27437","5077","19186","9975","18078","23784","4677","5069","5068","5071","20248","27438")

song_data_all <- data.frame(id=1,seqid=1,before="A",after="A")
song_data_all <- song_data_all[F,]
song_info_all <- data.frame(id=1,title="A",author="A")
song_info_all <- song_info_all[F,]

for(dataid in dataids){
  q <- html(paste0("http://www.ufret.jp/song.php?data=", dataid))

  # 曲名とタイトル
  song_info <- html_nodes(q, xpath = '//title') %>%
    html_text() %>%
    iconv("utf-8", "cp932") %>%
    str_replace_all(' ギターコード譜.+',"") %>%
    str_split(" / ")

  song_info_all <- merge(song_info_all, 
                         data.frame(id = dataid, title=song_info[[1]][[1]], author=song_info[[1]][[2]]),
                         all.x=T, all.y=T)

  song_code <- html_nodes(q, xpath = '//rt') %>%
    html_text() %>%
    iconv("utf-8", "cp932")

  #song_code <- data.frame(before=c("",song_code), after=c(song_code,""))
  song_data <- data.frame(id=dataid, seqid=1:(length(song_code)+1), before=c("",song_code), after=c(song_code,""))

  song_data_all <- merge(song_data_all, song_data, all.x=T, all.y=T)

  Sys.sleep(1)
}

visualize.R

nodes <- e[!is.na(str_match(e$LHS, "before")),]
nodes$LHS <- nodes$LHS %>% str_replace_all("\\{before=","") %>% str_replace_all("\\}","")
nodes$RHS <- nodes$RHS %>% str_replace_all("\\{after=","") %>% str_replace_all("\\}","")
nodes$mermaid <- paste0(nodes$LHS, "-->|", (floor(nodes$confidence*1000)/10), "%|", nodes$RHS)
nodes$mermaid <- str_replace_all(nodes$mermaid, "♭", "b")
mermaid(paste("graph TD",Reduce(function(...){paste(...,sep="\n")},nodes$mermaid),sep="\n"))