Inverse hyperbolic sine elementwise.
x : array_like
out : ndarray
arcsinh is a multivalued function: for each x there are infinitely many numbers z such that sinh(z) = x. The convention is to return the z whose imaginary part lies in [-pi/2, pi/2].
For real-valued input data types, arcsinh always returns real output. For each value that cannot be expressed as a real number or infinity, it returns nan and sets the invalid floating point error flag.
For complex-valued input, arccos is a complex analytical function that has branch cuts [1j, infj] and [-1j, -infj] and is continuous from the right on the former and from the left on the latter.
The inverse hyperbolic sine is also known as asinh or sinh^-1.
|||M. Abramowitz and I.A. Stegun, “Handbook of Mathematical Functions”, 10th printing, 1964, pp. 86. http://www.math.sfu.ca/~cbm/aands/|
|||Wikipedia, “Inverse hyperbolic function”, http://en.wikipedia.org/wiki/Arcsinh|
>>> np.arcsinh(np.array([np.e, 10.0])) array([ 1.72538256, 2.99822295])