Original Version

1 files changed, 23 insertions, 0 deletions

diff --git a/2.3-1/src/c/elementaryFunctions/atanh/datanhs.c b/2.3-1/src/c/elementaryFunctions/atanh/datanhs.c
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+++ b/2.3-1/src/c/elementaryFunctions/atanh/datanhs.c
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+/*
+ *  Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
+ *  Copyright (C) 2006-2008 - INRIA - Bruno JOFRET
+ *
+ *  This file must be used under the terms of the CeCILL.
+ *  This source file is licensed as described in the file COPYING, which
+ *  you should have received as part of this distribution.  The terms
+ *  are also available at
+ *  http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
+ *
+ */
+
+#include "atanh.h"
+#include "atan.h"
+/*
+//  METHOD
+//     based on the formula  atanh(z) = i atan(-i z)
+//
+// Real case : atanh(x) = -imag(atan(-i x))
+*/
+double	       datanhs(double x) {
+  return (-zimags(zatans(DoubleComplex(0.0, -x))));
+}