acot

Arguments

x

a real or complex array.

y

a real or complex array.

Description

Computes the element-wise inverse cotangent 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)) .

Sample

Examples

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

See also

• cotg — cotangente
• acotd — computes the element-wise inverse cotangent of the argument, result in degree.
• csgn — returns the sign of a vector of real of complex values
• acoth — cotangente hyperbolique inverse des éléments de l'argument.
• atan — 2-quadrant and 4-quadrant inverse tangent

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.