Merge pull request #337 from YichiZhang0613/fix_inconsistency

Fix wrong comment and add assertion

Author: tolik518

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "factorion-math"
-version = "1.0.3"
+version = "1.0.4"
 edition = "2024"
 description = "The math (factorials and related functions) used by factorion"
 license = "MIT"

factorion-math/Cargo.toml

@@ -339,7 +339,10 @@ pub fn approximate_termial_digits_float(k: u32, n: Float) -> Integer {
 /// Will panic if `x` is not finite.
 pub fn adjust_approximate((x, e): (Float, Integer)) -> (Float, Integer) {
     let prec = x.prec();
-    let (extra, _) = (x.clone().ln() / Float::with_val(prec, 10).ln())
+    if x == 0.0 {
+        return (Float::with_val(prec, 0), Integer::ZERO.clone());
+    }
+    let (extra, _) = (x.clone().abs().ln() / Float::with_val(prec, 10).ln())
         .to_integer_round(rug::float::Round::Down)
         .unwrap_or_else(|| panic!("Got non-finite number, x was {x}"));
     let x = x / (Float::with_val(prec, 10).pow(extra.clone()));