This function evaluates the Kelvin function of the second kind, ker, of order one.
Function Return Value
AKER1 — Function value. (Output)
Required Arguments
X — Argument for which the function value is desired. (Input) It must be nonnegative.
FORTRAN 90 Interface
Generic: AKER1 (X)
Specific: The specific interface names are S_AKER1 and D_AKER1.
FORTRAN 77 Interface
Single: AKER1 (X)
Double: The double precision name is DKER1.
Description
The modified Kelvin function ker1(x) is defined to be . The Bessel function K1(x) is defined in BSK1. Function AKER1 is based on the work of Burgoyne (1963).
If x < 0, then NaN (not a number) is returned. If x≥ 119, then zero is returned.
Example
In this example, ker1(0.4) is computed and printed.
