Remove character from string in R

问题

I have a data frame as given below:

data$Latitude
"+28.666428" "+28.666470" "+28.666376" "+28.666441" "+28.666330" "+28.666391"

str(data$Latitude)
Factor w/ 1368 levels "+10.037451","+10.037457",..

I want to remove the "+" character from each of the Latitude values. I tried using gsub()

data$Latitude<-gsub("+","",as.character(factor(data$Latitude)))

This isn't working.

回答1:

You can use a combination of sapply, substring and regexpr to achieve the result.
regexpr(<character>,<vector>)[1] gives you the index of the character.
Using the value as the start index for substring, the rest of the string can be separated.
sapply allows you loop through the values.

Here is the data.

d<-c("+28.666428","+28.666470","+28.666376","+28.666441","+28.666330")

Here is the logic.

v <- sapply(d, FUN = function(d){substring(d, regexpr('+',d) + 1, nchar(d))}, USE.NAMES=FALSE)  

Here is the output

> v
[1] "28.666428" "28.666470" "28.666376" "28.666441" "28.666330" "28.666391"

来源：https://stackoverflow.com/questions/42973681/remove-character-from-string-in-r