ATANH

Purpose:

Calculates the inverse hyperbolic tangent of any expression.

ATANH(val)

val

A scalar, series or table.

A scalar, series, or table.

atanh(-1..0.01..1);gridhv;griddot

$image\atanhpic01.gif$

displays the inverse hyperbolic tangent from –1 to 1.

atanh(i)

returns 0 + 0.785398 i or (π/4)i.

atanh(-2..0.1..2)

returns a 41 point real series.

The inverse hyperbolic tangent is defined as:

$image\atanh01.gif$

for all complex z. The function is multi-valued and this definition places the branch cut in the complex plane at [-∞, -1] and [1, ∞].

For |x| > 1, atanh(x) returns a complex result.

SETDEGREE and SETRADIAN have no effect on this function because it always operates in radians.