From f08690d79eeea6f564576cad6fa890d409eebe7d Mon Sep 17 00:00:00 2001
From: Vadim Nazarov <vdn@mailbox.org>
Date: Fri, 3 Apr 2015 17:03:07 +0300
Subject: [PATCH] add fix for chao1 function

---
 R/diversity.R | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/R/diversity.R b/R/diversity.R
index a7877e1..3eff888 100644
--- a/R/diversity.R
+++ b/R/diversity.R
@@ -119,7 +119,7 @@ chao1 <- function (.data) {
   # f1 != && f2 != 0
   else {
     const <- (n - 1) / n
-    e <- D + f1^2 / (2 * f1) * const
+    e <- D + f1^2 / (2 * f2) * const
     f12 <- f1 / f2
     v <- f2 * (const * f12^2 / 2 + const^2 * f12^3 + const^2 * f12^4 / 4)
     t <- e - D