Function nearest_k_spatial_tensor_parallel 

pub fn nearest_k_spatial_tensor_parallel<I: ChunkedNearestNeighborIndex + Sync>(
    index: &I,
    x: &[f32],
    y: &[f32],
    z: &[f32],
    tensor: &SpatialTensor<'_>,
    k: usize,
) -> Vec<(usize, Neighbor)>

Parallel k-NN search over SpatialTensor chunks.