SLATEC Routines --- DBESJ1 ---

*DECK DBESJ1
      DOUBLE PRECISION FUNCTION DBESJ1 (X)
C***BEGIN PROLOGUE  DBESJ1
C***PURPOSE  Compute the Bessel function of the first kind of order one.
C***LIBRARY   SLATEC (FNLIB)
C***CATEGORY  C10A1
C***TYPE      DOUBLE PRECISION (BESJ1-S, DBESJ1-D)
C***KEYWORDS  BESSEL FUNCTION, FIRST KIND, FNLIB, ORDER ONE,
C             SPECIAL FUNCTIONS
C***AUTHOR  Fullerton, W., (LANL)
C***DESCRIPTION
C
C DBESJ1(X) calculates the double precision Bessel function of the
C first kind of order one for double precision argument X.
C
C Series for BJ1        on the interval  0.          to  1.60000E+01
C                                        with weighted error   1.16E-33
C                                         log weighted error  32.93
C                               significant figures required  32.36
C                                    decimal places required  33.57
C
C***REFERENCES  (NONE)
C***ROUTINES CALLED  D1MACH, D9B1MP, DCSEVL, INITDS, XERMSG
C***REVISION HISTORY  (YYMMDD)
C   780601  DATE WRITTEN
C   890531  Changed all specific intrinsics to generic.  (WRB)
C   890531  REVISION DATE from Version 3.2
C   891214  Prologue converted to Version 4.0 format.  (BAB)
C   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ)
C   910401  Corrected error in code which caused values to have the
C           wrong sign for arguments less than 4.0.  (WRB)
C***END PROLOGUE  DBESJ1