From b45d93a7dc65c50cefc9299e6c2daf9cfe07e838 Mon Sep 17 00:00:00 2001
From: Quaternions <krakow20@gmail.com>
Date: Thu, 29 Aug 2024 13:16:09 -0700
Subject: [PATCH] more sqrt tests

---
 fixed_wide/src/tests.rs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/fixed_wide/src/tests.rs b/fixed_wide/src/tests.rs
index 3b40d7f..05c911a 100644
--- a/fixed_wide/src/tests.rs
+++ b/fixed_wide/src/tests.rs
@@ -25,3 +25,22 @@ fn test_sqrt_low(){
 	let b=a*a;
 	assert_eq!(b.sqrt(),a);
 }
+fn find_equiv_sqrt_via_f64(n:I32F32)->I32F32{
+	//GIMME THEM BITS BOY
+	let &[bits]=n.to_bits().to_bits().digits();
+	let ibits=bits as i64;
+	let f=(ibits as f64)/((1u64<<32) as f64);
+	let f_ans=f.sqrt();
+	let mut i=(f_ans*((1u64<<32) as f64)) as i64;
+	let s=(i as i128)*(i as i128);
+	if s<((ibits as i128)<<32){
+		i+=1;
+	}
+	I32F32::from_bits(bnum::BInt::<1>::from(i))
+}
+#[test]
+fn test_sqrt_exact(){
+	let a=I32F32::ONE*2;
+	let b=find_equiv_sqrt_via_f64(a);
+	assert_eq!(a.sqrt(),b);
+}