Moving average from data stream

#[test]
fn t1() {
    let start = std::time::Instant::now();
    let mut ma = MovingAverage::new(3);
    let val = ma.next(1);
    let expected = 1.0;
    log_result!((val - expected).abs() < 1e-5, "t1_next1", start, &expected, &val);
    assert!((val - expected).abs() < 1e-5);
}

#[test]
fn t2() {
    let start = std::time::Instant::now();
    let mut ma = MovingAverage::new(3);
    ma.next(1);
    let val = ma.next(10);
    let expected = 5.5;
    log_result!((val - expected).abs() < 1e-5, "t2_next2", start, &expected, &val);
    assert!((val - expected).abs() < 1e-5);
}

#[test]
fn t3() {
    let start = std::time::Instant::now();
    let mut ma = MovingAverage::new(3);
    ma.next(1);
    ma.next(10);
    let val = ma.next(3);
    let expected = 4.66667;
    log_result!((val - expected).abs() < 1e-4, "t3_next3", start, &expected, &val);
    assert!((val - expected).abs() < 1e-4);
}

#[test]
fn t4() {
    let start = std::time::Instant::now();
    let mut ma = MovingAverage::new(3);
    ma.next(1);
    ma.next(10);
    ma.next(3);
    let val = ma.next(5);
    let expected = 6.0;
    log_result!((val - expected).abs() < 1e-5, "t4_next4", start, &expected, &val);
    assert!((val - expected).abs() < 1e-5);
}

#[test]
fn t5() {
    let start = std::time::Instant::now();
    let mut ma = MovingAverage::new(1);
    let v1 = ma.next(5);
    let v2 = ma.next(10);
    log_result!((v1 - 5.0).abs() < 1e-5 && (v2 - 10.0).abs() < 1e-5, "t5_size1", start, &(5.0, 10.0), &(v1, v2));
    assert!((v1 - 5.0).abs() < 1e-5);
    assert!((v2 - 10.0).abs() < 1e-5);
}