Rで解析：Sankey Plotに便利です「sankey」パッケージ

#パッケージのインストール
install.packages("sankey")

#パッケージの読み込み
library("sankey")

###データ例の作成#####
n <- 15
#結合データを用意
#同じ長さの2つの配列
V1 <- sample(letters[1:24], n, replace = TRUE)
V2 <- sample(letters[1:24], n, replace = TRUE)

#配列からグラフ用のデータを作成
GraphText <- NULL
for(i in seq(V1)){
  
  GraphText <- paste(GraphText, V1[i], V2[i], "\n", sep = " ")
  
}
########

#edge読み込みデータの作成
edges <- read.table(stringsAsFactors = FALSE, textConnection(GraphText))

#edgeデータの作成:make_sankeyコマンド
PlotEdgeData <- make_sankey(edges = edges)
#構造の確認
str(PlotEdgeData)
List of 2
$ nodes:'data.frame':	16 obs. of  19 variables:
..$ id     : chr [1:16] "a" "t" "p" "v" ...
..$ col    : chr [1:16] "#2ca25f" "#2ca25f" "#2ca25f" "#2ca25f" ...
..$ shape  : chr [1:16] "rectangle" "rectangle" "rectangle" "rectangle" ...
..$ lty    : num [1:16] 1 1 1 1 1 1 1 1 1 1 ...
..$ srt    : num [1:16] 0 0 0 0 0 0 0 0 0 0 ...
..$ textcol: chr [1:16] "black" "black" "black" "black" ...
..$ label  : chr [1:16] "a" "t" "p" "v" ...
..$ adjx   : num [1:16] 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 ...
..$ adjy   : num [1:16] 1 1 1 1 1 1 1 1 1 1 ...
..$ boxw   : num [1:16] 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 ...
..$ cex    : num [1:16] 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 ...
..$ size   : num [1:16] 2 1 1 3 2 1 2 1 1 2 ...
..$ x      : num [1:16] 0 0 0 0 0 1 1 1 1 1 ...
..$ bottom : num [1:16] -1.35 -6.05 -9.75 -13.45 -19.15 ...
..$ top    : num [1:16] -3.35 -7.05 -10.75 -16.45 -21.15 ...
..$ center : num [1:16] -2.35 -6.55 -10.25 -14.95 -20.15 ...
..$ pos    : num [1:16] 2 2 2 2 2 1 1 1 1 1 ...
..$ textx  : num [1:16] -0.1 -0.1 -0.1 -0.1 -0.1 1 1 1 1 1 ...
..$ texty  : num [1:16] -2.35 -6.55 -10.25 -14.95 -20.15 ...
$ edges:'data.frame':	15 obs. of  6 variables:
..$ V1        : chr [1:15] "w" "w" "v" "v" ...
..$ V2        : chr [1:15] "e" "c" "c" "l" ...
..$ colorstyle: chr [1:15] "gradient" "gradient" "gradient" "gradient" ...
..$ curvestyle: chr [1:15] "sin" "sin" "sin" "sin" ...
..$ col       : chr [1:15] "#99d8c9" "#99d8c9" "#99d8c9" "#99d8c9" ...
..$ weight    : num [1:15] 1 1 1 1 1 1 1 1 1 1 ...
- attr(*, "class")= chr [1:3] "sankey" "simplegraph_df" "simplegraph"

#プロット:sankeyコマンド
sankey(PlotEdgeData)

###グラフ体裁はedgeデータ内容を変更します########
#ノードの色を変更
PlotEdgeData$nodes$col <- ifelse(PlotEdgeData$nodes$id %in% c("a", "p", "v", "h"), "blue", "#2ca25f")
#エッジの色を変更
PlotEdgeData$edges$col <- ifelse(PlotEdgeData$edges$V1 %in% c("a", "p", "v", "h"), "red", "yellow")
#エッジの塗りつぶし方法を変更
PlotEdgeData$edges$colorstyle <- ifelse(PlotEdgeData$edges$V1 %in% c("a", "p", "v", "h"), "col", "gradient")
#エッジの塗りつぶし方法を変更
PlotEdgeData$edges$curvestyle <- ifelse(PlotEdgeData$edges$V1 %in% c("a", "p", "v", "h"), "line", "sin")
#プロット
sankey(PlotEdgeData)