This function calculates the secant of specified complex number.
IMSEC(complex_num)
The complex_num argument is a complex number to return the secant for.
An error is returned if the complex_num argument is not in the form "x+yi" or "x+yj".
Accepts numeric and string data. Returns string data.
IMSEC("11-2i") gives the result 0.00126
IMSEC("3-6i") gives the result -0.00490