如何手動創建樹狀圖（或「hclust」）對象？ （in R）

Question

我有一個樹形圖給我作爲圖像。由於它不是很大，我可以將它「手工」構造成一個R對象。

所以我的問題是如何手動創建樹狀圖（或「hclust」）對象，當我擁有的是樹狀圖像？

我看到有一個叫做「as.dendrogram」的函數，但我沒有找到如何使用它的例子。

（PS：這篇文章是由here以下我的問題）

非常感謝， 塔爾

Answer 1

我認爲你是在創建一個hclust對象，然後將其轉換爲使用as.dendrogram樹狀圖的更好，然後嘗試直接創建樹狀圖。查看?hclust幫助頁面，查看hclust對象元素的含義。

下面是一個簡單的例子有四片葉子A，B，C，和d，結合第一AB，然後是CD，最後AB-CD：

a <- list() # initialize empty object 
# define merging pattern: 
# negative numbers are leaves, 
# positive are merged clusters (defined by row number in $merge) 
a$merge <- matrix(c(-1, -2, 
        -3, -4, 
        1, 2), nc=2, byrow=TRUE) 
a$height <- c(1, 1.5, 3) # define merge heights 
a$order <- 1:4    # order of leaves(trivial if hand-entered) 
a$labels <- LETTERS[1:4] # labels of leaves 
class(a) <- "hclust"  # make it an hclust object 
plot(a)      # look at the result 

#convert to a dendrogram object if needed 
ad <- as.dendrogram(a) 

Answer 2

完全手冊......不建議大數據集。

tree<-list(); 
attributes(tree)<-list(members=18,height=3); 
class(tree)<-"dendrogram"; 

tree[[1]]<-list(); 
attributes(tree[[1]])<-list(members=4,height=2,edgetext="1"); 
tree[[1]][[1]]<-list(); 
attributes(tree[[1]][[1]])<-list(members=2,height=1,edgetext="H"); 
    tree[[1]][[1]][[1]]<-list(); 
    attributes(tree[[1]][[1]][[1]])<-list(members=1,height=0,edgetext="H",label="1HH",leaf=TRUE); 
    tree[[1]][[1]][[2]]<-list(); 
    attributes(tree[[1]][[1]][[2]])<-list(members=1,height=0,edgetext="T",label="1HT",leaf=TRUE); 
tree[[1]][[2]]<-list(); 
attributes(tree[[1]][[2]])<-list(members=2,height=1,edgetext="T"); 
    tree[[1]][[2]][[1]]<-list(); 
    attributes(tree[[1]][[2]][[1]])<-list(members=1,height=0,edgetext="H",label="1TH",leaf=TRUE); 
    tree[[1]][[2]][[2]]<-list(); 
    attributes(tree[[1]][[2]][[2]])<-list(members=1,height=0,edgetext="T",label="1TT",leaf=TRUE); 
tree[[2]]<-list(); 
attributes(tree[[2]])<-list(members=2,height=2,edgetext="2"); 
tree[[2]][[1]]<-list(); 
attributes(tree[[2]][[1]])<-list(members=1,height=0,edgetext="H",label="2H",leaf=TRUE); 
tree[[2]][[2]]<-list(); 
attributes(tree[[2]][[2]])<-list(members=1,height=0,edgetext="T",label="2T",leaf=TRUE); 
tree[[3]]<-list(); 
attributes(tree[[3]])<-list(members=4,height=2,edgetext="3"); 
tree[[3]][[1]]<-list(); 
attributes(tree[[3]][[1]])<-list(members=2,height=1,edgetext="H"); 
    tree[[3]][[1]][[1]]<-list(); 
    attributes(tree[[3]][[1]][[1]])<-list(members=1,height=0,edgetext="H",label="3HH",leaf=TRUE); 
    tree[[3]][[1]][[2]]<-list(); 
    attributes(tree[[3]][[1]][[2]])<-list(members=1,height=0,edgetext="T",label="3HT",leaf=TRUE); 
tree[[3]][[2]]<-list(); 
attributes(tree[[3]][[2]])<-list(members=2,height=1,edgetext="T"); 
    tree[[3]][[2]][[1]]<-list(); 
    attributes(tree[[3]][[2]][[1]])<-list(members=1,height=0,edgetext="H",label="3TH",leaf=TRUE); 
    tree[[3]][[2]][[2]]<-list(); 
    attributes(tree[[3]][[2]][[2]])<-list(members=1,height=0,edgetext="T",label="3TT",leaf=TRUE); 
tree[[4]]<-list(); 
attributes(tree[[4]])<-list(members=2,height=2,edgetext="4"); 
tree[[4]][[1]]<-list(); 
attributes(tree[[4]][[1]])<-list(members=1,height=0,edgetext="H",label="4H",leaf=TRUE); 
tree[[4]][[2]]<-list(); 
attributes(tree[[4]][[2]])<-list(members=1,height=0,edgetext="T",label="4T",leaf=TRUE); 
tree[[5]]<-list(); 
attributes(tree[[5]])<-list(members=4,height=2,edgetext="5"); 
tree[[5]][[1]]<-list(); 
attributes(tree[[5]][[1]])<-list(members=2,height=1,edgetext="H"); 
    tree[[5]][[1]][[1]]<-list(); 
    attributes(tree[[5]][[1]][[1]])<-list(members=1,height=0,edgetext="H",label="5HH",leaf=TRUE); 
    tree[[5]][[1]][[2]]<-list(); 
    attributes(tree[[5]][[1]][[2]])<-list(members=1,height=0,edgetext="T",label="5HT",leaf=TRUE); 
tree[[5]][[2]]<-list(); 
attributes(tree[[5]][[2]])<-list(members=2,height=1,edgetext="T"); 
    tree[[5]][[2]][[1]]<-list(); 
    attributes(tree[[5]][[2]][[1]])<-list(members=1,height=0,edgetext="H",label="5TH",leaf=TRUE); 
    tree[[5]][[2]][[2]]<-list(); 
    attributes(tree[[5]][[2]][[2]])<-list(members=1,height=0,edgetext="T",label="5TT",leaf=TRUE); 
tree[[6]]<-list(); 
attributes(tree[[6]])<-list(members=2,height=2,edgetext="6"); 
tree[[6]][[1]]<-list(); 
attributes(tree[[6]][[1]])<-list(members=1,height=0,edgetext="H",label="6H",leaf=TRUE); 
tree[[6]][[2]]<-list(); 
attributes(tree[[6]][[2]])<-list(members=1,height=0,edgetext="T",label="6T",leaf=TRUE); 


windows(width=3,rescale="fixed"); 
par(ps=8); 
plot(rev(tree),center=TRUE,horiz=TRUE);