BER1
This function evaluates the Kelvin function of the first kind, ber, of order one.
Function Return Value
BER1 — Function value. (Output)
Required Arguments
X — Argument for which the function value is desired. (Input)
FORTRAN 90 Interface
Generic: BER1 (X)
Specific: The specific interface names are S_BER1 and D_BER1.
FORTRAN 77 Interface
Single: BER1 (X)
Double: The double precision name is DBER1.
Description
The Kelvin function ber1(x) is defined to be J1(xe3πi4). The Bessel function J1(x) is defined in BSJ1. Function BER1 is based on the work of Burgoyne (1963).
If x > 119, then NaN (not a number) is returned.
Example
In this example, ber1(0.4) is computed and printed.
 
USE BER1_INT
USE UMACH_INT
 
IMPLICIT NONE
! Declare variables
INTEGER NOUT
REAL VALUE, X
! Compute
X = 0.4
VALUE = BER1(X)
! Print the results
CALL UMACH (2, NOUT)
WRITE (NOUT,99999) X, VALUE
99999 FORMAT (' BER1(', F6.3, ') = ', F6.3)
END
Output
 
BER1( 0.400) = -0.144
Published date: 03/19/2020
Last modified date: 03/19/2020