Compiler Library/XL Reference Manual (32650-90029)

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Accuracy
Attributes
Parameter: A real number.
Result: A representable real number in the range [0.0,
1.0]. See Chapter 1 for details on the
internal representation of real numbers.
HP FORTRAN 77/XL: Intrinsic function: Y=TANH(X).
Error: If the argument is a NaN, there are two
possible actions. If the INVALID trap is
enabled, the message "TANH(X): X=NaN" occurs.
Otherwise, the INVALID flag is set. In either
case, a quiet NaN is returned.
When x-y ~ , maximum f-g ~ sech
2
x