Subject: 30.0.50; Wrong definition of gamma function in calc.texi [PATCH]
From: Vladimir Nikishkin <[email-masked]>
To: [email-masked]
Date: Thu, 15 Jun 2023 12:25:04 +0800
List-Id: <debbugs-submit.debbugs.gnu.org>

No Emacs code is affected, but the Gamma Function is defined by a
convergent integral, not a divergent one.

Patch below:

---   doc/misc/calc.texi
@@ -18614,7 +18614,7 @@ Advanced Math Functions
 factorial function:  @samp{gamma(n+1) = fact(n)}.  For general complex
 arguments the gamma function can be defined by the following definite
 integral:
-@texline @math{\Gamma(a) = \int_0^\infty t^{a-1} e^t dt}.
+@texline @math{\Gamma(a) = \int_0^\infty t^{a-1} e^{-t} dt}.
 @infoline @expr{gamma(a) = integ(t^(a-1) exp(t), t, 0, inf)}.
 (The actual implementation uses far more efficient computational methods.)

-- 
Your sincerely,
Vladimir Nikishkin (MiEr, lockywolf)
(Laptop)