00001 SUBROUTINE ZBUNK(ZR, ZI, FNU, KODE, MR, N, YR, YI, NZ, TOL, ELIM, 00002 * ALIM) 00003 C***BEGIN PROLOGUE ZBUNK 00004 C***REFER TO ZBESK,ZBESH 00005 C 00006 C ZBUNK COMPUTES THE K BESSEL FUNCTION FOR FNU.GT.FNUL. 00007 C ACCORDING TO THE UNIFORM ASYMPTOTIC EXPANSION FOR K(FNU,Z) 00008 C IN ZUNK1 AND THE EXPANSION FOR H(2,FNU,Z) IN ZUNK2 00009 C 00010 C***ROUTINES CALLED ZUNK1,ZUNK2 00011 C***END PROLOGUE ZBUNK 00012 C COMPLEX Y,Z 00013 DOUBLE PRECISION ALIM, AX, AY, ELIM, FNU, TOL, YI, YR, ZI, ZR 00014 INTEGER KODE, MR, N, NZ 00015 DIMENSION YR(N), YI(N) 00016 NZ = 0 00017 AX = DABS(ZR)*1.7321D0 00018 AY = DABS(ZI) 00019 IF (AY.GT.AX) GO TO 10 00020 C----------------------------------------------------------------------- 00021 C ASYMPTOTIC EXPANSION FOR K(FNU,Z) FOR LARGE FNU APPLIED IN 00022 C -PI/3.LE.ARG(Z).LE.PI/3 00023 C----------------------------------------------------------------------- 00024 CALL ZUNK1(ZR, ZI, FNU, KODE, MR, N, YR, YI, NZ, TOL, ELIM, ALIM) 00025 GO TO 20 00026 10 CONTINUE 00027 C----------------------------------------------------------------------- 00028 C ASYMPTOTIC EXPANSION FOR H(2,FNU,Z*EXP(M*HPI)) FOR LARGE FNU 00029 C APPLIED IN PI/3.LT.ABS(ARG(Z)).LE.PI/2 WHERE M=+I OR -I 00030 C AND HPI=PI/2 00031 C----------------------------------------------------------------------- 00032 CALL ZUNK2(ZR, ZI, FNU, KODE, MR, N, YR, YI, NZ, TOL, ELIM, ALIM) 00033 20 CONTINUE 00034 RETURN 00035 END
1.7.1
