1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
use std::ops::Sub;
use super::number::Number;
/// Returns the absolute value of number `n`.
///
/// # Arguments
///
/// * `n` - The number to calculate absolute value.
///
/// # Returns
///
/// Absolute value of number `n`.
///
/// # Examples
///
/// ```
/// use rufl::math;
///
/// assert_eq!(1, math::abs(-1).unwrap());
///
/// assert_eq!(2 as i8, math::abs(-2 as i8).unwrap());
///
/// assert_eq!(0.1, math::abs(-0.1).unwrap());
///
/// ```
pub fn abs<T: Number + Sub<Output = T>>(n: T) -> Result<T, String> {
if n == T::MIN {
Err("Overflow: minimum value can't be representable".to_string())
} else if n < T::ZERO {
Ok(T::ZERO - n)
} else {
Ok(n)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_abs() {
assert_eq!(0.1 as f32, abs(-0.1 as f32).unwrap());
assert_eq!(0.2, abs(-0.2).unwrap());
assert_eq!(1, abs(-1).unwrap());
assert_eq!(2 as i8, abs(-2 as i8).unwrap());
}
}