From 51eb5beab56dabead088f093fd12f3dc1d25adf4 Mon Sep 17 00:00:00 2001
From: Rob Adams <rob@ebeep.org>
Date: Wed, 20 May 2020 03:05:03 +0000
Subject: [PATCH] fix: sqrt_double hangs on x < 1 (#760)

---
 math/sqrt_double.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/math/sqrt_double.cpp b/math/sqrt_double.cpp
index e3418bfc3..5a0fd1c88 100644
--- a/math/sqrt_double.cpp
+++ b/math/sqrt_double.cpp
@@ -6,6 +6,9 @@ number in O(logn) time,
 with precision fixed */
 
 double Sqrt(double x) {
+    if ( x > 0 && x < 1 ) {
+        return 1/Sqrt(1/x);
+    }
     double l = 0, r = x;
     /* Epsilon is the precision. 
     A great precision is