SLATEC Routines --- ZACAI ---

*DECK ZACAI
      SUBROUTINE ZACAI (ZR, ZI, FNU, KODE, MR, N, YR, YI, NZ, RL, TOL,
     +   ELIM, ALIM)
C***BEGIN PROLOGUE  ZACAI
C***SUBSIDIARY
C***PURPOSE  Subsidiary to ZAIRY
C***LIBRARY   SLATEC
C***TYPE      ALL (CACAI-A, ZACAI-A)
C***AUTHOR  Amos, D. E., (SNL)
C***DESCRIPTION
C
C     ZACAI APPLIES THE ANALYTIC CONTINUATION FORMULA
C
C         K(FNU,ZN*EXP(MP))=K(FNU,ZN)*EXP(-MP*FNU) - MP*I(FNU,ZN)
C                 MP=PI*MR*CMPLX(0.0,1.0)
C
C     TO CONTINUE THE K FUNCTION FROM THE RIGHT HALF TO THE LEFT
C     HALF Z PLANE FOR USE WITH ZAIRY WHERE FNU=1/3 OR 2/3 AND N=1.
C     ZACAI IS THE SAME AS ZACON WITH THE PARTS FOR LARGER ORDERS AND
C     RECURRENCE REMOVED. A RECURSIVE CALL TO ZACON CAN RESULT IF ZACON
C     IS CALLED FROM ZAIRY.
C
C***SEE ALSO  ZAIRY
C***ROUTINES CALLED  D1MACH, ZABS, ZASYI, ZBKNU, ZMLRI, ZS1S2, ZSERI
C***REVISION HISTORY  (YYMMDD)
C   830501  DATE WRITTEN
C   910415  Prologue converted to Version 4.0 format.  (BAB)
C***END PROLOGUE  ZACAI