BESSELK

Description: Returns the modified Bessel function Kn(x), which is equivalent to the Bessel function evaluated for purely imaginary arguments.

Syntax: BESSELK(Number, Order)

• Number is the value at which to evaluate the function.

• Order is the order of the function.

Remarks:

• Both arguments must be numerical.

• Order must be >= 0 and an integer.

• The n-th order modified Bessel function of the variable x is:

where Jn and Yn are the J and Y Bessel functions, respectively.

• When used in an event analysis flowchart, the parameters must evaluate to numerical values. They can include:

• Numerical values

• Standard operands (+, -, *, /)

• Predefined mathematical functions (exp, log, sin, etc.)

• Event analysis internal functions

• Event analysis resources

• References to any ReliaSoft Workbooks

Example:

• Compute the Modified Bessel function at x = 1.5 with an order of n = 1.

BESSELK(1.5, 1) = (0.277388)