Averages/Simple moving average: Difference between revisions

=={{header|Rust}}==

===Vector Based===

<lang rust>struct SimpleMovingAverage {

period: usize,

numbers: Vec<usize>

}

impl SimpleMovingAverage {

fn new(p: usize) -> SimpleMovingAverage {

SimpleMovingAverage {

period: p,

numbers: Vec::new()

}

}

fn add_number(&mut self, number: usize) -> f64 {

self.numbers.push(number);

if self.numbers.len() > self.period {

self.numbers.remove(0);

}

if self.numbers.is_empty() {

return 0f64;

}else {

let sum = self.numbers.iter().fold(0, |acc, x| acc+x);

return sum as f64 / self.numbers.len() as f64;

}

}

}

fn main() {

for period in [3, 5].iter() {

println!("Moving average with period {}", period);

let mut sma = SimpleMovingAverage::new(*period);

for i in [1, 2, 3, 4, 5, 5, 4, 3, 2, 1].iter() {

println!("Number: {} | Average: {}", i, sma.add_number(*i));

}

}

}</lang>

<pre>Moving average with period 3

Number: 1 | Average: 1

Number: 2 | Average: 1.5

Number: 3 | Average: 2

Number: 4 | Average: 3

Number: 5 | Average: 4

Number: 5 | Average: 4.666666666666667

Number: 4 | Average: 4.666666666666667

Number: 3 | Average: 4

Number: 2 | Average: 3

Number: 1 | Average: 2

Moving average with period 5

Number: 1 | Average: 1

Number: 2 | Average: 1.5

Number: 3 | Average: 2

Number: 4 | Average: 2.5

Number: 5 | Average: 3

Number: 5 | Average: 3.8

Number: 4 | Average: 4.2

Number: 3 | Average: 4.2

Number: 2 | Average: 3.8

Number: 1 | Average: 3

</pre>