pub fn substring_by_char<OffsetSize: OffsetSizeTrait>(
array: &GenericStringArray<OffsetSize>,
start: i64,
length: Option<u64>,
) -> Result<GenericStringArray<OffsetSize>, ArrowError>
Expand description
Substrings based on character index
§Arguments
-
array
- The input string array -
start
- The start index of all substrings. Ifstart >= 0
, then count from the start of the string, otherwise count from the end of the string. -
length
(option) - The length of all substrings. Iflength
isNone
, then the substring is fromstart
to the end of the string.
Attention: Both start
and length
are counted by char.
§Performance
This function is slower than substring. Theoretically, the time complexity
is O(n)
where n
is the length of the value buffer. It is recommended to
use substring if the input array only contains ASCII chars.
§Basic usage
let array = StringArray::from(vec![Some("arrow"), None, Some("Γ ⊢x:T")]);
let result = substring_by_char(&array, 1, Some(4)).unwrap();
assert_eq!(result, StringArray::from(vec![Some("rrow"), None, Some(" ⊢x:")]));