From: Taylor R Campbell <campbell@mumble.net>
Date: Sun, 18 Nov 2018 03:36:52 +0000 (+0000)
Subject: Teach (log1p x) to return complex results for real x < -1.
X-Git-Tag: mit-scheme-pucked-10.1.2~16^2~37
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=f3a2daf645ff0415ead5a67b311b14d7e9ac78cb;p=mit-scheme.git

Teach (log1p x) to return complex results for real x < -1.
---

diff --git a/src/runtime/arith.scm b/src/runtime/arith.scm
index d8e0b5faa..e5409c8cd 100644
--- a/src/runtime/arith.scm
+++ b/src/runtime/arith.scm
@@ -1744,7 +1744,9 @@ USA.
       ((copy real:expm1) z)))
 
 (define (complex:log1p z)
-  (if (recnum? z)
+  (if (or (recnum? z)
+	  (and (real:real? z)
+	       (<= z -1)))
       (complex:log (complex:+ z 1))	;XXX
       ((copy real:log1p) z)))
 
diff --git a/tests/runtime/test-arith.scm b/tests/runtime/test-arith.scm
index 362087ec6..c93f276d5 100644
--- a/tests/runtime/test-arith.scm
+++ b/tests/runtime/test-arith.scm
@@ -252,7 +252,7 @@ USA.
    (list 0.25 .22314355131420976)
    (list (- 1 (sqrt 1/2)) 0.25688251232181475)
    (list 0.3 .26236426446749106)
-   (list -2 +3.141592653589793i 'xfail))
+   (list -2 +3.141592653589793i))
   (lambda (v)
     (let ((x (car v))
           (z (cadr v))