str_replace() is used to replace the given string with a particular value in R Programming Language. It is available in stringr library, so we have to load this library.
Syntax:
str_replace( "replacing string", "replaced string")
where,
- replacing string is the string to be replaced
- replaced string is the final string
We will use str_replace in dataframe. We can replace particular string in dataframe column by using the following syntax
str_replace(dataframe$column_name, "replacing string", "replaced string")
where,
- dataframe is the input dataframe
- column_name is the column in the dataframe
Example:
# load the library
library(stringr)
# create a dataframe with 3 columns
data = data.frame(name1=c('java', 'python', 'php'),
name2=c('html', 'css', 'jsp'),
marks=c(78, 89, 77))
# replace the java with oops in name1 column
print(str_replace(data$name1, "java", "oops"))
# replace the htmlwith oops in name2 column
print(str_replace(data$name2, "html", "HTML5"))
Output:
[1] "oops" "python" "php" [1] "HTML5" "css" "jsp"
Method 2: Replace String with Nothing
We can replace the string with "" empty.
Syntax:
str_replace(dataframe$column_name, "replacing string", "")
Example :
# load the library
library(stringr)
# create a dataframe with 3 columns
data = data.frame(name1=c('java', 'python', 'php'),
name2=c('html', 'css', 'jsp'),
marks=c(78, 89, 77))
# replace the java with nothing in name1 column
print(str_replace(data$name1, "java", ""))
# replace the html with nothing in name2 column
print(str_replace(data$name2, "html", ""))
Output:
[1] "" "python" "php" [1] "" "css" "jsp"
Method 3: Replace Multiple Strings
We can replace multiple string in a particular column by using str_replace_all method.
Syntax:
str_replace_all(dataframe$column_name, c("string1" = "new string",.................,"stringn" = "new string"))
Example:
# load the library
library(stringr)
# create a dataframe with 3 columns
data = data.frame(name1=c('java', 'python', 'php'),
name2=c('html', 'css', 'jsp'),
marks=c(78, 89, 77))
# replace the java with oops and php with sql in name1 column
print(str_replace_all(data$name1, c("java"="oops", "php"="sql")))
# replace the html with r and jsp with servletsin name2 column
print(str_replace_all(data$name2, c("html"="R", "jsp"="servlets")))
Output:
[1] "oops" "python" "sql" [1] "R" "css" "servlets"