From 8d84138897671dbbe329e0308e74ab445ea0e286 Mon Sep 17 00:00:00 2001
From: "Matthew R. Becker" <beckermr@users.noreply.github.com>
Date: Thu, 29 Sep 2016 17:10:33 -0500
Subject: [PATCH] BUG clip effective sample size at maximum number of samples

---
 pymc3/diagnostics.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pymc3/diagnostics.py b/pymc3/diagnostics.py
index dfdaa3a8b9..838b29bcd0 100644
--- a/pymc3/diagnostics.py
+++ b/pymc3/diagnostics.py
@@ -259,7 +259,7 @@ def calc_n_eff(x):
 
             t += 1
 
-        return int(m * n / (1. + 2 * rho[1:t].sum()))
+        return min(m * n, int(m * n / (1. + 2 * rho[1:t].sum())))
 
     n_eff = {}
     for var in mtrace.varnames: