vortex_array/arrays/list/vtable/
operations.rs

1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: Copyright the Vortex contributors
3
4use std::ops::Range;
5use std::sync::Arc;
6
7use vortex_scalar::Scalar;
8
9use crate::ArrayRef;
10use crate::IntoArray;
11use crate::arrays::ListArray;
12use crate::arrays::ListVTable;
13use crate::vtable::OperationsVTable;
14use crate::vtable::ValidityHelper;
15
16impl OperationsVTable<ListVTable> for ListVTable {
17    fn slice(array: &ListArray, range: Range<usize>) -> ArrayRef {
18        ListArray::new(
19            array.elements().clone(),
20            array.offsets().slice(range.start..range.end + 1),
21            array.validity().slice(range),
22        )
23        .into_array()
24    }
25
26    fn scalar_at(array: &ListArray, index: usize) -> Scalar {
27        // By the preconditions we know that the list scalar is not null.
28        let elems = array.list_elements_at(index);
29        let scalars: Vec<Scalar> = (0..elems.len()).map(|i| elems.scalar_at(i)).collect();
30
31        Scalar::list(
32            Arc::new(elems.dtype().clone()),
33            scalars,
34            array.dtype().nullability(),
35        )
36    }
37}