Function test_underflow 

pub fn test_underflow(result: &Float, o: Ordering) -> bool

Given the (Float, Ordering) result of an operation, determines whether an underflow occurred.

We’re defining an underflow to occur whenever the actual result is outside the representable finite range, and is rounded to zero, to the minimum positive value, or to the maximum negative value. An underflow can present itself in four ways:

• The result is $0.0$ or $-0.0$ and the Ordering is Less
• The result is $0.0$ or $-0.0$ and the Ordering is Greater
• The result is the smallest positive value and the Ordering is Greater
• The result is the largest (least negative) negative value and the Ordering is Less

Worst-case complexity

$T(n) = O(n)$

$M(n) = O(1)$

where $T$ is time, $M$ is additional memory, and $n$ is self.significant_bits().

Examples

use malachite_base::num::basic::traits::{One, Zero};
use malachite_float::{test_underflow, Float};
use std::cmp::Ordering::*;

assert!(test_underflow(&Float::ZERO, Less));
assert!(test_underflow(&Float::ZERO, Greater));
assert!(test_underflow(&Float::min_positive_value_prec(10), Greater));
assert!(test_underflow(&-Float::min_positive_value_prec(10), Less));

assert!(!test_underflow(&Float::ZERO, Equal));
assert!(!test_underflow(&Float::ONE, Less));