tanhreturns a value for the hyperbolic tangent, .
For full information please refer to the NAG Library document for s10aa
The argument of the function.
The value of the hyperbolic tangent, .
tanhcalculates an approximate value for the hyperbolic tangent of its argument, .
For it is based on the Chebyshev expansion
For , to within the representation accuracy of the machine and so this approximation is used.
NIST Digital Library of Mathematical Functions