SLATEC Routines --- DBSI1E ---

*DECK DBSI1E
      DOUBLE PRECISION FUNCTION DBSI1E (X)
C***BEGIN PROLOGUE  DBSI1E
C***PURPOSE  Compute the exponentially scaled modified (hyperbolic)
C            Bessel function of the first kind of order one.
C***LIBRARY   SLATEC (FNLIB)
C***CATEGORY  C10B1
C***TYPE      DOUBLE PRECISION (BESI1E-S, DBSI1E-D)
C***KEYWORDS  EXPONENTIALLY SCALED, FIRST KIND, FNLIB,
C             HYPERBOLIC BESSEL FUNCTION, MODIFIED BESSEL FUNCTION,
C             ORDER ONE, SPECIAL FUNCTIONS
C***AUTHOR  Fullerton, W., (LANL)
C***DESCRIPTION
C
C DBSI1E(X) calculates the double precision exponentially scaled
C modified (hyperbolic) Bessel function of the first kind of order
C one for double precision argument X.  The result is I1(X)
C multiplied by EXP(-ABS(X)).
C
C Series for BI1        on the interval  0.          to  9.00000E+00
C                                        with weighted error   1.44E-32
C                                         log weighted error  31.84
C                               significant figures required  31.45
C                                    decimal places required  32.46
C
C Series for AI1        on the interval  1.25000E-01 to  3.33333E-01
C                                        with weighted error   2.81E-32
C                                         log weighted error  31.55
C                               significant figures required  29.93
C                                    decimal places required  32.38
C
C Series for AI12       on the interval  0.          to  1.25000E-01
C                                        with weighted error   1.83E-32
C                                         log weighted error  31.74
C                               significant figures required  29.97
C                                    decimal places required  32.66
C
C***REFERENCES  (NONE)
C***ROUTINES CALLED  D1MACH, DCSEVL, INITDS, XERMSG
C***REVISION HISTORY  (YYMMDD)
C   770701  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***END PROLOGUE  DBSI1E