Name

acot — computes the element-wise inverse cotangeant of the argument.

Calling Sequence

y = acot(x)

Parameters

x

Real or complex array.

y

Real or complex array.

Description

Computes the element-wise inverse cotangeant of the argument. For real argument the result is real.

The following equalities hold: acot(z) = %pi-acot(-z)=%pi/2-atan(z)=%i*acoth(%i*z)+%pi/2*(1-csgn(z+%i))

Examples

 
x=[1 2 -2 sqrt(2) -sqrt(2) 2/sqrt(3) -2/sqrt(3) -1];
acot(x)/%pi
 

See Also

cotg, acotd

References

Kahan, W., "Branch cuts for complex elementary functions, or, Much ado about nothing's sign bit", Proceedings of the joing IMA/SIAM conference on The State of the Art in Numerical Analysis, University of Birmingham, A. Iserles and M.J.D. Powell, eds, Clarendon Press, Oxford, 1987, 165-210.

Authors

Serge Steer, INRIA