创建一个逗号分隔的向量

我有一个数值向量，我要把它变成一个字符向量 每个元素用逗号分隔。

> one = c(1:5)
> paste(as.character(one), collapse=", ")
[1] "1, 2, 3, 4, 5"
> paste(as.character(one), sep="' '", collapse=", ")
[1] "1, 2, 3, 4, 5"

但是，我希望输出看起来像:

"1", "2", "3", "4", "5"

我是否遗漏了粘贴函数中的某些参数？ 救命! ？

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Assuming you want your output in a character string (as opposed to a vector of characters) you could try:

paste("'",as.character(one),"'",collapse=", ",sep="")

That gives you single quotes around the numbers rather than double quotes, but it's basically what you seem to want.

And you can always escape to get double quotes:

rs <- paste("\"",as.character(one),"\"",collapse=", ",sep="")
cat(rs)

that should print out what you want with the double quotes.

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最佳答案

shQuote is probably the best way to do this. Specifically, this gets you the output you want:

cat(paste(shQuote(one, type="cmd"), collapse=", "))

If single quotes are fine, you can use:

paste(shQuote(one), collapse=", ")

type="cmd" actually provides escaped quotes, which is what's actually useful for most contexts, but if you really want to display it somewhere with unescaped quotes, cat provides that.

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You say you want a character vector with that output, but others who find this question may be looking for one of these functions instead:

First, a way to get output ready for input to R; that would be dput:

> dput(as.character(one))
c("1", "2", "3", "4", "5")

Second, a way to output a csv file, which would be write.csv or write.table. These functions take a parameter file, not used here, to directly output to a file.

> write.table(matrix(as.character(one),nrow=1), sep=",",
row.names=FALSE, col.names=FALSE)
"1","2","3","4","5"


> write.csv(matrix(as.character(one),nrow=1),row.names=FALSE)
"V1","V2","V3","V4","V5"
"1","2","3","4","5"
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In addition to shQuote, see the functions sQuote and dQuote to wrap text in single and double quotes respectively. You'll also want to set options(useFancyQuotes=FALSE) to get plain (unidirectional) ASCII quotes.

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Just to add on to Noah's answer if you want to use the paste function:

paste(shQuote(one, type="sh"), collapse=", ")

Should give you:

[1] '1','2','3','4','5'
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Something similar with toString

toString(paste0("'",1:10,"'") )

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