Function interleave

ciphercore-base/src/ops/adder.rs:218–231

Takes arrays `[a1, a2, ..., a_n]` and `[b1, b2, ..., b_n]` Returns `[a1, b1, a2, b2, ..., a_n, b_n]`

(first: Node, second: Node)

///
/// Returns `[a1, b1, a2, b2, ..., a_n, b_n]`
fn interleave(first: Node, second: Node) -> Result<Node> {
    let first = expand_dims(first, &[0])?;
    let second = expand_dims(second, &[0])?;
    let graph = first.get_graph();
    let joined = graph.concatenate(vec![first, second], 0)?;
    let mut axes: Vec<_> = (0..joined.get_type()?.get_shape().len() as u64).collect();
    axes.swap(0, 1);
    let joined = joined.permute_axes(axes)?;
    let mut shape = joined.get_type()?.get_shape();
    shape[0] *= 2;
    shape.remove(1);
    let scalar = joined.get_type()?.get_scalar_type();
    joined.reshape(array_type(shape, scalar))
}

/// This function generates a graph for the "segment tree" to calculate
/// carry bits.