From af6562721bb97e7d0067a27a3162220cae9f9508 Mon Sep 17 00:00:00 2001
From: Abdulaziz Ghuloum <aghuloum@cs.indiana.edu>
Date: Fri, 4 Jan 2008 21:46:50 -0500
Subject: [PATCH] Fixes bug 180170: Missing bignum sqrt

---
 scheme/ikarus.numerics.ss | 12 +++++++++++-
 scheme/last-revision      |  2 +-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/scheme/ikarus.numerics.ss b/scheme/ikarus.numerics.ss
index 5e73ba6..a0b43d7 100644
--- a/scheme/ikarus.numerics.ss
+++ b/scheme/ikarus.numerics.ss
@@ -2065,7 +2065,17 @@
       (cond
         [(flonum? x) (foreign-call "ikrt_fl_sqrt" x)]
         [(fixnum? x) (foreign-call "ikrt_fx_sqrt" x)]
-        [(bignum? x) (die 'sqrt "BUG: bignum sqrt not implemented")]
+        [(bignum? x) 
+         (unless ($bignum-positive? x) 
+           (error 'sqrt "complex results not supported" x))
+         (let-values ([(s r) (exact-integer-sqrt x)])
+           (cond
+             [(eq? r 0) s]
+             [else 
+              (let ([v (sqrt (inexact x))])
+                (cond
+                  [(infinite? v) (inexact s)]
+                  [else v]))]))]
         [(ratnum? x) (/ (sqrt ($ratnum-n x)) (sqrt ($ratnum-d x)))]
         [else (die 'sqrt "BUG: unsupported" x)])))
 
diff --git a/scheme/last-revision b/scheme/last-revision
index a38c571..7ae5be6 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1328
+1329