Mercurial > hg > octave-nkf
view libcruft/blas/icamax.f @ 9003:0631d397fbe0
replace lo_ieee_isnan by xisnan, add missing includes
author | Jaroslav Hajek <highegg@gmail.com> |
---|---|
date | Sat, 21 Mar 2009 20:46:21 +0100 |
parents | c42ba026faf1 |
children |
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INTEGER FUNCTION ICAMAX(N,CX,INCX) * .. Scalar Arguments .. INTEGER INCX,N * .. * .. Array Arguments .. COMPLEX CX(*) * .. * * Purpose * ======= * * finds the index of element having max. absolute value. * jack dongarra, linpack, 3/11/78. * modified 3/93 to return if incx .le. 0. * modified 12/3/93, array(1) declarations changed to array(*) * * * .. Local Scalars .. REAL SMAX INTEGER I,IX * .. * .. External Functions .. REAL SCABS1 EXTERNAL SCABS1 * .. ICAMAX = 0 IF (N.LT.1 .OR. INCX.LE.0) RETURN ICAMAX = 1 IF (N.EQ.1) RETURN IF (INCX.EQ.1) GO TO 20 * * code for increment not equal to 1 * IX = 1 SMAX = SCABS1(CX(1)) IX = IX + INCX DO 10 I = 2,N IF (SCABS1(CX(IX)).LE.SMAX) GO TO 5 ICAMAX = I SMAX = SCABS1(CX(IX)) 5 IX = IX + INCX 10 CONTINUE RETURN * * code for increment equal to 1 * 20 SMAX = SCABS1(CX(1)) DO 30 I = 2,N IF (SCABS1(CX(I)).LE.SMAX) GO TO 30 ICAMAX = I SMAX = SCABS1(CX(I)) 30 CONTINUE RETURN END