用`gsub`替换点 [英] Replace dots using `gsub`

问题描述

我正在尝试替换所有的."在数据框的特定列中使用"/".每个单元格中还有其他字符，我想确保只更改.". 当我使用gsub时，我得到的输出似乎可以进行更改，但是当我转到View()时，实际上并没有进行更改...我认为gsub应该实际上是在更改数据帧中的值.我使用不正确吗?我下面有我的代码.

I am trying to replace all the "." in a specific column of my data frame with "/". There are other characters in each cell and I want to make sure I only change the "."'s. When I use gsub, I get an output that appears to make the changes, but then when I go to View(), the changes are not actually made...I thought gsub was supposed to actually change the value in the data frame. Am I using it incorrectly? I have my code below.

gsub(".", "/", spy$Identifier, ignore.case = FALSE, perl = FALSE,
    fixed = TRUE, useBytes = FALSE)

我也尝试了sub，但是下面的代码将每个条目本身更改为"/"，我不确定如何更改它.

I also tried sub, but the code I have below changed every entry itself to "/" and I am not sure how to change it.

spy$Identifier <- sub("^(.).*", "/", spy$Identifier)

谢谢！

推荐答案

我的建议是转义".字符:

My recommendation would be to escape the "." character:

        spy$Identifier <- gsub("\\.", "/", spy$Identifier)

在正则表达式中，句点是与任何字符匹配的特殊字符. 转义"它告诉搜索寻找实际时期.在R的gsub中，这是通过两个反斜杠(即:"\\")完成的.在其他语言中，它通常只是一个反斜杠.

In regular expression, a period is a special character that matches any character. "Escaping" it tells the search to look for an actual period. In R's gsub this is accomplished with two backslashes (i.e.: "\\"). In other languages, it's often just one backslash.

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