DOUBLE PRECISION FUNCTION DBESY0(X)
C***BEGIN PROLOGUE  DBESY0
C***DATE WRITTEN   770701   (YYMMDD)
C***REVISION DATE  820801   (YYMMDD)
C***CATEGORY NO.  C10A1
C***KEYWORDS  BESSEL FUNCTION,DOUBLE PRECISION,ORDER ZERO,SECOND KIND,
C             SPECIAL FUNCTION
C***AUTHOR  FULLERTON, W., (LANL)
C***PURPOSE  Computes the d.p. Bessel function of the second kind of
C            order zero.
C***DESCRIPTION
C
C DBESY0(X) calculates the double precision Bessel function of the
C second kind of order zero for double precision argument X.
C
C Series for BY0        on the interval  0.          to  1.60000E+01
C                                        with weighted error   8.14E-32
C                                         log weighted error  31.09
C                               significant figures required  30.31
C                                    decimal places required  31.73
C***REFERENCES  (NONE)
C***ROUTINES CALLED  D1MACH,D9B0MP,DBESJ0,DCSEVL,INITDS,XERROR
C***END PROLOGUE  DBESY0