Question

我有以下列表

  t <- c(22, 22, 8, 8, 8, 8, 8, 8, 8, 8, 8, 4, 4, 4, 4, 4, 4, 4, 18, 
    18, 18, 12, 12, 12, 1, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 
    7, 7, 7, 7, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 6, 
    6, 6, 6, 6, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 
    21, 20, 20, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 11, 11, 11, 11, 11, 
    11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 2, 2, 2, 3, 3, 3, 3, 
    5, 5, 5, 5, 5, 10, 10, 10, 17, 17, 17, 14, 14, 15, 15, 15)

我想用这段代码为每种颜色分配颜色

library(RColorBrewer)
rowcol <- colorRampPalette(brewer.pal(8,"Dark2"))
rowcol(length(unique(t)))[t]

但是为什么会产生NAs？

 [1] NA        NA        "#A66F20" "#A66F20" "#A66F20" "#A66F20" "#A66F20" "#A66F20" "#A66F20" "#A66F20" "#A66F20"
 [12] "#578A52" "#578A52" "#578A52" "#578A52" "#578A52" "#578A52" "#578A52" "#8A6C8D" "#8A6C8D" "#8A6C8D" "#C9611D"
 [23] "#C9611D" "#C9611D" "#1B9E77" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D"
 [34] "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#93762D" "#7F6EA0" "#7F6EA0"
 [45] "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F6EA0" "#7F7C39"
 [56] "#7F7C39" "#7F7C39" "#7F7C39" "#7F7C39" NA        NA        NA        NA        NA        NA        NA       
 [67] NA        NA        NA        NA        NA        NA        NA        "#7570B3" "#7570B3" "#BB6814" "#BB6814"
 [78] "#BB6814" "#BB6814" "#BB6814" "#BB6814" "#BB6814" "#BB6814" "#BB6814" "#BB6814" "#D35F0B" "#D35F0B" "#D35F0B"
 [89] "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B" "#D35F0B"
[100] "#D35F0B" "#2F976A" "#2F976A" "#2F976A" "#43905E" "#43905E" "#43905E" "#43905E" "#6B8345" "#6B8345" "#6B8345"
[111] "#6B8345" "#6B8345" "#CE6208" "#CE6208" "#CE6208" "#946A7B" "#946A7B" "#946A7B" "#B46543" "#B46543" "#A96755"
[122] "#A96755" "#A96755"

在一天结束时，我想在RowSideColors中将此最终向量用作heatmap.2参数。

Answer 1

让我们使用你的矢量＆＃34; t＆＃34;：

unique(t)的长度是多少？

length(unique(t))
# 20

如果我们使用rowcol会发生什么：

pal <- rowcol(length(unique(t)))
pal
#  [1] "#1B9E77" "#61864B" "#A66F20" "#CE6014" "#A96755" "#846D97" "#8D61AA" "#B7469B" "#E12C8C" "#BE5067" "#8E7E40"
# [12] "#6CA61C" "#9BA812" "#CBA907" "#DBA206" "#C48F10" "#AC7B1A" "#957130" "#7D6B4B" "#666666"

length(pal)
# 20

＆＃34; t＆＃34;的最大值是什么，即

max(t)
# 22

我们清楚地看到pal的长度和＆＃34; t＆＃34;的最大值不匹配。这就是为什么当＆＃34; t＆＃34;如果等于21或22，则得NA。

您需要使用rowcol(max(t))[t]

Answer 2

因为：

length(unique(t))
#> [1] 20
max(t)
#> [1] 22
all(is.na(rowcol(length(unique(t)))[t]) == (t>20))
#> [1] TRUE

并且索引超出其索引的向量长度并不是错误;当索引（t）超过其索引（rowcol(length(unique(t)))）

的对象时，R只返回NA＆＃s

为什么colorRampPalette会产生NA？

2 个答案: