ATANH intrinsic function

Standard: F77 F90 F95 F2003 F2008 Example program



X : Real or Complex;

Result : Same type and kind as X.


The value of the result is an approximation to the arc hyperbolic tangent of X. Like many intrinsic functions, this is elemental; the result has the same shape as X, with the operation being applied elementwise.

If X is of type Real, it must lie in the range −1<X<+1 (the result is infinite if ABS(X)==1, and NaN if ABS(X)>1). If X is of type Complex, the imaginary part of the result is in radians, in the range −π/2≤AIMAG(ATANH(X))≤π/2.


ATAN intrinsic function, TANH intrinsic function.