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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package math
/*
* tanh(x) computes the hyperbolic tangent of its floating
* point argument.
*
* sinh and cosh are called except for large arguments, which
* would cause overflow improperly.
*/
// Tanh computes the hyperbolic tangent of x.
func Tanh(x float64) float64 {
if x < 0 {
x = -x
if x > 21 {
return -1
}
return -Sinh(x) / Cosh(x)
}
if x > 21 {
return 1
}
return Sinh(x) / Cosh(x)
}