Mercurial > octave
view liboctave/external/amos/zs1s2.f @ 23434:f4d4d83f15c5
maint: rename cruft/ directory to external/
* liboctave/external: Renamed from liboctave/cruft.
*
* configure.ac: Rename XTRA_CRUFT_SH_LDFLAGS to XTRA_EXTERNAL_SH_LDFLAGS.
Rename CRUFT_DLL_DEFS to EXTERNAL_DLL_DEFS.
* install.txi: Update documentation to refer to liboctave/external.
* HACKING: Update explanation of directory tree.
* liboctave/module.mk: Update build system to include liboctave/external
* liboctave/numeric/module.mk: Update CPPFLAGS to find Faddeeva in external/
directory.
* lo-blas-proto.h, lo-lapack-proto.h: Update comments which referred to cruft
directory.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 24 Apr 2017 21:03:38 -0700 |
parents | liboctave/cruft/amos/zs1s2.f@648dabbb4c6b |
children |
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SUBROUTINE ZS1S2(ZRR, ZRI, S1R, S1I, S2R, S2I, NZ, ASCLE, ALIM, * IUF) C***BEGIN PROLOGUE ZS1S2 C***REFER TO ZBESK,ZAIRY C C ZS1S2 TESTS FOR A POSSIBLE UNDERFLOW RESULTING FROM THE C ADDITION OF THE I AND K FUNCTIONS IN THE ANALYTIC CON- C TINUATION FORMULA WHERE S1=K FUNCTION AND S2=I FUNCTION. C ON KODE=1 THE I AND K FUNCTIONS ARE DIFFERENT ORDERS OF C MAGNITUDE, BUT FOR KODE=2 THEY CAN BE OF THE SAME ORDER C OF MAGNITUDE AND THE MAXIMUM MUST BE AT LEAST ONE C PRECISION ABOVE THE UNDERFLOW LIMIT. C C***ROUTINES CALLED XZABS,XZEXP,XZLOG C***END PROLOGUE ZS1S2 C COMPLEX CZERO,C1,S1,S1D,S2,ZR DOUBLE PRECISION AA, ALIM, ALN, ASCLE, AS1, AS2, C1I, C1R, S1DI, * S1DR, S1I, S1R, S2I, S2R, ZEROI, ZEROR, ZRI, ZRR, XZABS INTEGER IUF, IDUM, NZ DATA ZEROR,ZEROI / 0.0D0 , 0.0D0 / NZ = 0 AS1 = XZABS(S1R,S1I) AS2 = XZABS(S2R,S2I) IF (S1R.EQ.0.0D0 .AND. S1I.EQ.0.0D0) GO TO 10 IF (AS1.EQ.0.0D0) GO TO 10 ALN = -ZRR - ZRR + DLOG(AS1) S1DR = S1R S1DI = S1I S1R = ZEROR S1I = ZEROI AS1 = ZEROR IF (ALN.LT.(-ALIM)) GO TO 10 CALL XZLOG(S1DR, S1DI, C1R, C1I, IDUM) C1R = C1R - ZRR - ZRR C1I = C1I - ZRI - ZRI CALL XZEXP(C1R, C1I, S1R, S1I) AS1 = XZABS(S1R,S1I) IUF = IUF + 1 10 CONTINUE AA = DMAX1(AS1,AS2) IF (AA.GT.ASCLE) RETURN S1R = ZEROR S1I = ZEROI S2R = ZEROR S2I = ZEROI NZ = 1 IUF = 0 RETURN END