6.15 Trim and Pad

20180608 One of the major challenges of string parsing is removing and adding whitespaces and wrapping text.

Additional white space can be present on the left, right or both sides of the word. The stringr::str_trim() function offers an effective way to get rid of these whitespaces.

ws <- c(" abc",  "def ", " ghi ")
str_trim(ws)
## [1] "abc" "def" "ghi"
str_trim(ws, side="left")
## [1] "abc"  "def " "ghi "
str_trim(ws, side="right")
## [1] " abc" "def"  " ghi"
str_trim(ws, side="both")
## [1] "abc" "def" "ghi"

Conversely we can also pad a string with additional characters for up to a specified width using stringr::str_pad(). The default padding character is a space but we can override that.

str_pad("abc", width=7)
## [1] "    abc"
str_pad("abc", width=7, side="left")
## [1] "    abc"
str_pad("abc", width=7, side="right")
## [1] "abc    "
str_pad("abc", width=7, side="both", pad="#")
## [1] "##abc##"


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