sec
The trigonometric secant function.
Syntax

sec(x)

x
is a real or complex number.

Description
sec(z)
is defined as 1 / cos(z)
for all complex z
.
Notes
If you want to specify the argument in degrees, you can use the ° postfix operator, which amounts to multiplication by π/180.
Examples
sec(π/3)
2
sec(30°)
1.15470053838 (=(2/3)⋅√3)
sec(i)
0.648054273664