arrow/benches/length_kernel.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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// under the License.

#[macro_use]
extern crate criterion;
use criterion::Criterion;

extern crate arrow;

use arrow::array::*;
use arrow::compute::kernels::length::length;

fn bench_length(array: &StringArray) {
    criterion::black_box(length(array).unwrap());
}

fn add_benchmark(c: &mut Criterion) {
    fn double_vec<T: Clone>(v: Vec<T>) -> Vec<T> {
        [&v[..], &v[..]].concat()
    }

    // double ["hello", " ", "world", "!"] 10 times
    let mut values = vec!["one", "on", "o", ""];
    for _ in 0..10 {
        values = double_vec(values);
    }
    let array = StringArray::from(values);

    c.bench_function("length", |b| b.iter(|| bench_length(&array)));
}

criterion_group!(benches, add_benchmark);
criterion_main!(benches);