tanh(3I)

NAME
     TANH, DTANH, QTANH - Computes hyperbolic tangent

SYNOPSIS
     TANH ([X=]x)
     DTANH ([X=]x)
     QTANH ([X=]x)

IMPLEMENTATION
     UNICOS, UNICOS/mk, IRIX systems

     CF90, MIPSpro 7 Fortran 90, MIPSpro Fortran 77

STANDARDS
     Fortran

     Fortran extension:  QTANH

DESCRIPTION
     The TANH, DTANH, and QTANH intrinsic functions compute the hyperbolic
     tangent of x.  These functions evaluate y = tanh(x).  They are
     elemental functions.  They accept the following argument:

     x         Must be of type real.  The type and kind type of x is
               identical to the type and kind type of the return value.
               See the RETURN VALUES section for information on input data
               types and return values.

     TANH is the generic function name; the others are specifics.

NOTES
     The TANH and DTANH intrinsic function names can be passed as
     arguments; the other cannot.

     On CRAY T90 systems that support IEEE arithmetic, these return values
     occur:

          TANH(x) = 1.0 if x > 19.1

          TANH(x) = -1.0 if x < -19.1

          TANH(NaN) = NaN

RETURN VALUES
     TANH returns the real hyperbolic tangent of its real argument.

     DTANH returns the double-precision real hyperbolic tangent of its
     double-precision argument.

     QTANH returns the quad-precision real hyperbolic tangent of its
     quad-precision argument.

SEE ALSO
     Intrinsic Procedures Reference Manual for the printed version of this
     man page.