Extract the nth non-numeric substring from a string.

Extract the nth non-numeric bit of a string where numbers are optionally defined with decimals, scientific notation and thousand separators.

str_first_non_numeric(...) is just str_nth_non_numeric(..., n = 1).
str_last_non_numeric(...) is just str_nth_non_numeric(..., n = -1).

str_nth_non_numeric(
  string,
  n,
  decimals = FALSE,
  leading_decimals = decimals,
  negs = FALSE,
  sci = FALSE,
  big_mark = "",
  commas = FALSE
)

str_first_non_numeric(
  string,
  decimals = FALSE,
  leading_decimals = decimals,
  negs = FALSE,
  sci = FALSE,
  big_mark = "",
  commas = FALSE
)

str_last_non_numeric(
  string,
  decimals = FALSE,
  leading_decimals = decimals,
  negs = FALSE,
  sci = FALSE,
  big_mark = ""
)

Arguments

string: A string.
n: A vector of integerish values. Must be either length 1 or have length equal to the length of string. Negative indices count from the back: while n = 1 and n = 2 correspond to first and second, n = -1 and n = -2 correspond to last and second-last. n = 0 will return NA.
decimals: Do you want to include the possibility of decimal numbers (TRUE) or not (FALSE, the default).
leading_decimals: Do you want to allow a leading decimal point to be the start of a number?
negs: Do you want to allow negative numbers? Note that double negatives are not handled here (see the examples).
sci: Make the search aware of scientific notation e.g. 2e3 is the same as 2000.
big_mark: A character. Allow this character to be used as a thousands separator. This character will be removed from between digits before they are converted to numeric. You may specify many at once by pasting them together e.g. big_mark = ",_" will allow both commas and underscores. Internally, this will be used inside a [] regex block so e.g. "a-z" will behave differently to "az-". Most common separators (commas, spaces, underscores) should work fine.
commas: Deprecated. Use big_mark instead.

Examples

strings <- c(
  "abc123def456", "abc-0.12def.345", "abc.12e4def34.5e9",
  "abc1,100def1,230.5", "abc1,100e3,215def4e1,000"
)
str_nth_non_numeric(strings, n = 2)
#> [1] "def" "."   "e"   ","   ","  
str_nth_non_numeric(strings, n = -2, decimals = TRUE)
#> [1] "abc"  "abc-" "def"  "def"  "e"   
str_first_non_numeric(strings, decimals = TRUE, leading_decimals = FALSE)
#> [1] "abc"  "abc-" "abc." "abc"  "abc" 
str_last_non_numeric(strings, big_mark = ",")
#> [1] "def"  "def." "e"    "."    "e"   
str_nth_non_numeric(strings,
  n = 1, decimals = TRUE, leading_decimals = TRUE,
  sci = TRUE
)
#> [1] "abc"  "abc-" "abc"  "abc"  "abc" 
str_first_non_numeric(strings,
  decimals = TRUE, leading_decimals = TRUE,
  sci = TRUE, big_mark = ",", negs = TRUE
)
#> [1] "abc" "abc" "abc" "abc" "abc"
str_first_non_numeric(c("22", "1.2.3"), decimals = TRUE)
#> Warning: `NA`s introduced by ambiguity.
#> ℹ The first such ambiguity is in string number 2 which is '1.2.3'.
#> ✖ The offending part of that string is '.2.3'.
#> [1] NA NA

Extract the `n`th non-numeric substring from a string.

Arguments

See also

Examples