s****y
发帖数: 297 | 1 比如我有一列变量如下：
x <- c("d",rep("a",2),"c",rep("b",6),rep("c",3),"a","a","b",rep("d",8))
这样x 为："d" "a" "a" "a" "a" "a" "c" "b" "b" "b" "b" "b" "b" "c" "c" "c" "a
" "a" "b" "d" "d" "d" "d" "d" "d" "d" "d"
x有四种值："d" "a" "c" "b"
我想做的事情是：当某一种值的个数少于5个的时候，将它替换成统一的字符“o”.
这样结果将会是："d" "o" "o" "o" "b" "b" "b" "b" "b" "b" "o" "o" "o" "o" "o"
"b" "d" "d" "d" "d" "d" "d" "d" "d"
也就是原数据中a和c全部被替换成了o。
我能想到的是用for 循环做对每种值逐一替换。
请大牛们指点一下：能否避免用for循环，直接用什么命令就可以解决的？
因为数据太庞大，用for循环的话时间太长了。。。。
非常感谢！！！ | s*****n
发帖数: 2174 | 2 temp <- tapply(x, x, length)
x[x %in% names(temp)[temp < 5]] <- "o"
"a
"
【在 s****y 的大作中提到】
: 比如我有一列变量如下：
: x <- c("d",rep("a",2),"c",rep("b",6),rep("c",3),"a","a","b",rep("d",8))
: 这样x 为："d" "a" "a" "a" "a" "a" "c" "b" "b" "b" "b" "b" "b" "c" "c" "c" "a
: " "a" "b" "d" "d" "d" "d" "d" "d" "d" "d"
: x有四种值："d" "a" "c" "b"
: 我想做的事情是：当某一种值的个数少于5个的时候，将它替换成统一的字符“o”.
: 这样结果将会是："d" "o" "o" "o" "b" "b" "b" "b" "b" "b" "o" "o" "o" "o" "o"
: "b" "d" "d" "d" "d" "d" "d" "d" "d"
: 也就是原数据中a和c全部被替换成了o。
: 我能想到的是用for 循环做对每种值逐一替换。
| l*********s
发帖数: 5409 | 3
so cool
【在 s*****n 的大作中提到】
: temp <- tapply(x, x, length)
: x[x %in% names(temp)[temp < 5]] <- "o"
:
: "a
: "
| s****y
发帖数: 297 | |
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