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See the recommended documentation of this function

Scilab help >> Elementary Functions > Trigonometry > asech


computes the element-wise inverse hyperbolic secant of the argument.

Calling Sequence

y = asech(x)



Real or complex array.


Real or complex array.


Computes the element-wise inverse hyperbolic secant of the argument. If the argument is real and have absolute value less than one the result is real.

The following equalities hold: asech(x) = acosh(1 ./ x)= %i*csgn(%i*(1−1 ./ x))*asec(x)=csgn(%i*(1 − 1 ./ x))*(%pi/2*(%i+acsch(%i*x)))



See Also

  • sech — Compute the element-wise hyperbolic secant of the argument.


  • 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.


  • Serge Steer, INRIA
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Last updated:
Wed Oct 05 12:09:40 CEST 2011