MATLAB Functions

Secant and hyperbolic secant

Y = sec(X)
Y = sech(X)

Description

The sec and sech commands operate element-wise on arrays. The functions' domains and ranges include complex values. All angles are in radians.

Y = sec(X)

returns an array the same size as X containing the secant of the elements of X.

Y = sech(X)

returns an array the same size as X containing the hyperbolic secant of the elements of X.

Examples

Graph the secant over the domains

and

and the hyperbolic secant over the domain

x1 = -pi/2+0.01:0.01:pi/2-0.01; 
x2 = pi/2+0.01:0.01:(3*pi/2)-0.01; 
plot(x1,sec(x1),x2,sec(x2))
x = -2*pi:0.01:2*pi; plot(x,sech(x))

The expression sec(pi/2) does not evaluate as infinite but as the reciprocal of the floating-point accuracy eps, because pi is a floating-point approximation to the exact value of

Algorithm