BEI0
This function evaluates the Kelvin function of the first kind, bei, of order zero.
Function Return Value
BEI0 — Function value. (Output)
Required Arguments
X — Argument for which the function value is desired. (Input)
ABS(X) must be less than 119.
FORTRAN 90 Interface
Generic: BEI0 (X)
Specific: The specific interface names are S_BEI0 and D_BEI0.
FORTRAN 77 Interface
Single: BEI0 (X)
Double: The double precision name is DBEI0.
Description
The Kelvin function bei
0(
x) is defined to be
ℑJ0(
xe3πi∕4). The Bessel function
J0(
x) is defined in
BSJ0. Function
BEI0 is based on the work of Burgoyne (1963).
In BEI0, x must be less than 119.
Example
In this example, bei0(0.4) is computed and printed.
USE BEI0_INT
USE UMACH_INT
IMPLICIT NONE
! Declare variables
INTEGER NOUT
REAL VALUE, X
! Compute
X = 0.4
VALUE = BEI0(X)
! Print the results
CALL UMACH (2, NOUT)
WRITE (NOUT,99999) X, VALUE
99999 FORMAT (' BEI0(', F6.3, ') = ', F6.3)
END
Output
BEI0( 0.400) = 0.040
