BERP0
This function evaluates the derivative of the Kelvin function of the first kind, ber, of order zero.
Function Return Value
BERP0 — Function value. (Output)
Required Arguments
X — Argument for which the function value is desired. (Input)
FORTRAN 90 Interface
Generic: BERP0 (X)
Specific: The specific interface names are S_BERP0 and D_BERP0.
FORTRAN 77 Interface
Single: BERP0 (X)
Double: The double precision name is DBERP0.
Description
The function berʹ0(x) is defined to be
where ber0(x) is a Kelvin function, see BER0. Function BERP0 is based on the work of Burgoyne (1963).
If x > 119, then NaN (not a number) is returned.
Example
In this example, berʹ0(0.6) is computed and printed.
 
USE BERP0_INT
USE UMACH_INT
 
IMPLICIT NONE
! Declare variables
INTEGER NOUT
REAL VALUE, X
! Compute
X = 0.6
VALUE = BERP0(X)
! Print the results
CALL UMACH (2, NOUT)
WRITE (NOUT,99999) X, VALUE
99999 FORMAT (' BERP0(', F6.3, ') = ', F6.3)
END
Output
 
BERP0( 0.600) = -0.013