mirror of
https://git.planet-casio.com/Lephenixnoir/OpenLibm.git
synced 2024-12-29 13:03:42 +01:00
99 lines
3.6 KiB
Fortran
99 lines
3.6 KiB
Fortran
SUBROUTINE ZACAI(ZR, ZI, FNU, KODE, MR, N, YR, YI, NZ, RL, TOL,
|
|
* ELIM, ALIM)
|
|
C***BEGIN PROLOGUE ZACAI
|
|
C***REFER TO ZAIRY
|
|
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***ROUTINES CALLED ZASYI,ZBKNU,ZMLRI,ZSERI,ZS1S2,D1MACH,ZABS
|
|
C***END PROLOGUE ZACAI
|
|
C COMPLEX CSGN,CSPN,C1,C2,Y,Z,ZN,CY
|
|
DOUBLE PRECISION ALIM, ARG, ASCLE, AZ, CSGNR, CSGNI, CSPNR,
|
|
* CSPNI, C1R, C1I, C2R, C2I, CYR, CYI, DFNU, ELIM, FMR, FNU, PI,
|
|
* RL, SGN, TOL, YY, YR, YI, ZR, ZI, ZNR, ZNI, D1MACH, ZABS
|
|
INTEGER INU, IUF, KODE, MR, N, NN, NW, NZ
|
|
DIMENSION YR(N), YI(N), CYR(2), CYI(2)
|
|
DATA PI / 3.14159265358979324D0 /
|
|
NZ = 0
|
|
ZNR = -ZR
|
|
ZNI = -ZI
|
|
AZ = ZABS(COMPLEX(ZR,ZI))
|
|
NN = N
|
|
DFNU = FNU + DBLE(FLOAT(N-1))
|
|
IF (AZ.LE.2.0D0) GO TO 10
|
|
IF (AZ*AZ*0.25D0.GT.DFNU+1.0D0) GO TO 20
|
|
10 CONTINUE
|
|
C-----------------------------------------------------------------------
|
|
C POWER SERIES FOR THE I FUNCTION
|
|
C-----------------------------------------------------------------------
|
|
CALL ZSERI(ZNR, ZNI, FNU, KODE, NN, YR, YI, NW, TOL, ELIM, ALIM)
|
|
GO TO 40
|
|
20 CONTINUE
|
|
IF (AZ.LT.RL) GO TO 30
|
|
C-----------------------------------------------------------------------
|
|
C ASYMPTOTIC EXPANSION FOR LARGE Z FOR THE I FUNCTION
|
|
C-----------------------------------------------------------------------
|
|
CALL ZASYI(ZNR, ZNI, FNU, KODE, NN, YR, YI, NW, RL, TOL, ELIM,
|
|
* ALIM)
|
|
IF (NW.LT.0) GO TO 80
|
|
GO TO 40
|
|
30 CONTINUE
|
|
C-----------------------------------------------------------------------
|
|
C MILLER ALGORITHM NORMALIZED BY THE SERIES FOR THE I FUNCTION
|
|
C-----------------------------------------------------------------------
|
|
CALL ZMLRI(ZNR, ZNI, FNU, KODE, NN, YR, YI, NW, TOL)
|
|
IF(NW.LT.0) GO TO 80
|
|
40 CONTINUE
|
|
C-----------------------------------------------------------------------
|
|
C ANALYTIC CONTINUATION TO THE LEFT HALF PLANE FOR THE K FUNCTION
|
|
C-----------------------------------------------------------------------
|
|
CALL ZBKNU(ZNR, ZNI, FNU, KODE, 1, CYR, CYI, NW, TOL, ELIM, ALIM)
|
|
IF (NW.NE.0) GO TO 80
|
|
FMR = DBLE(FLOAT(MR))
|
|
SGN = -DSIGN(PI,FMR)
|
|
CSGNR = 0.0D0
|
|
CSGNI = SGN
|
|
IF (KODE.EQ.1) GO TO 50
|
|
YY = -ZNI
|
|
CSGNR = -CSGNI*DSIN(YY)
|
|
CSGNI = CSGNI*DCOS(YY)
|
|
50 CONTINUE
|
|
C-----------------------------------------------------------------------
|
|
C CALCULATE CSPN=EXP(FNU*PI*I) TO MINIMIZE LOSSES OF SIGNIFICANCE
|
|
C WHEN FNU IS LARGE
|
|
C-----------------------------------------------------------------------
|
|
INU = INT(SNGL(FNU))
|
|
ARG = (FNU-DBLE(FLOAT(INU)))*SGN
|
|
CSPNR = DCOS(ARG)
|
|
CSPNI = DSIN(ARG)
|
|
IF (MOD(INU,2).EQ.0) GO TO 60
|
|
CSPNR = -CSPNR
|
|
CSPNI = -CSPNI
|
|
60 CONTINUE
|
|
C1R = CYR(1)
|
|
C1I = CYI(1)
|
|
C2R = YR(1)
|
|
C2I = YI(1)
|
|
IF (KODE.EQ.1) GO TO 70
|
|
IUF = 0
|
|
ASCLE = 1.0D+3*D1MACH(1)/TOL
|
|
CALL ZS1S2(ZNR, ZNI, C1R, C1I, C2R, C2I, NW, ASCLE, ALIM, IUF)
|
|
NZ = NZ + NW
|
|
70 CONTINUE
|
|
YR(1) = CSPNR*C1R - CSPNI*C1I + CSGNR*C2R - CSGNI*C2I
|
|
YI(1) = CSPNR*C1I + CSPNI*C1R + CSGNR*C2I + CSGNI*C2R
|
|
RETURN
|
|
80 CONTINUE
|
|
NZ = -1
|
|
IF(NW.EQ.(-2)) NZ=-2
|
|
RETURN
|
|
END
|