diff options
Diffstat (limited to 'src/c/elementaryFunctions/cosh/i16coshs.c')
-rw-r--r-- | src/c/elementaryFunctions/cosh/i16coshs.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/src/c/elementaryFunctions/cosh/i16coshs.c b/src/c/elementaryFunctions/cosh/i16coshs.c new file mode 100644 index 0000000..7d6084f --- /dev/null +++ b/src/c/elementaryFunctions/cosh/i16coshs.c @@ -0,0 +1,27 @@ +/* + * Scilab ( http://www.scilab.org/ ) - This file is part of Scilab + * Copyright (C) 2008-2008 - 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 + * + */ + +/* +// cosh(z) = 0.5 (exp(|z|) + exp(-|z|)) +// = 0.5 ( y + 1/y ) with y = exp(|z|) +*/ + +#include <math.h> +#include "cosh.h" +#include "exp.h" +#include "abs.h" +#include "types.h" + +float i16coshs(int16 x) { + double y = i16exps(i16abss(x)); + return (0.5 * (y + 1.0/y)); +} |