Function arrow2::compute::if_then_else::if_then_else

pub fn if_then_else(
    predicate: &BooleanArray, 
    lhs: &dyn Array, 
    rhs: &dyn Array
) -> Result<Box<dyn Array>>

Returns the values from lhs if the predicate is true or from the rhs if the predicate is false Returns None if the predicate is None.

Example

use arrow2::compute::if_then_else::if_then_else;
use arrow2::array::{Int32Array, BooleanArray};

let lhs = Int32Array::from_slice(&[1, 2, 3]);
let rhs = Int32Array::from_slice(&[4, 5, 6]);
let predicate = BooleanArray::from(&[Some(true), None, Some(false)]);
let result = if_then_else(&predicate, &lhs, &rhs)?;

let expected = Int32Array::from(&[Some(1), None, Some(6)]);

assert_eq!(expected, result.as_ref());