Function arrow::compute::kernels::window::shift

pub fn shift(array: &dyn Array, offset: i64) -> Result<ArrayRef>

Shifts array by defined number of items (to left or right) A positive value for offset shifts the array to the right a negative value shifts the array to the left.

Examples

use arrow::array::Int32Array;
use arrow::error::Result;
use arrow::compute::shift;

let a: Int32Array = vec![Some(1), None, Some(4)].into();

// shift array 1 element to the right
let res = shift(&a, 1).unwrap();
let expected: Int32Array = vec![None, Some(1), None].into();
assert_eq!(res.as_ref(), &expected);

// shift array 1 element to the left
let res = shift(&a, -1).unwrap();
let expected: Int32Array = vec![None, Some(4), None].into();
assert_eq!(res.as_ref(), &expected);

// shift array 0 element, although not recommended
let res = shift(&a, 0).unwrap();
let expected: Int32Array = vec![Some(1), None, Some(4)].into();
assert_eq!(res.as_ref(), &expected);

// shift array 3 element tot he right
let res = shift(&a, 3).unwrap();
let expected: Int32Array = vec![None, None, None].into();
assert_eq!(res.as_ref(), &expected);