Mercurial > octave-nkf
view libcruft/blas/scasum.f @ 7789:82be108cc558
First attempt at single precision tyeps
* * *
corrections to qrupdate single precision routines
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prefer demotion to single over promotion to double
* * *
Add single precision support to log2 function
* * *
Trivial PROJECT file update
* * *
Cache optimized hermitian/transpose methods
* * *
Add tests for tranpose/hermitian and ChangeLog entry for new transpose code
author | David Bateman <dbateman@free.fr> |
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date | Sun, 27 Apr 2008 22:34:17 +0200 |
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REAL FUNCTION SCASUM(N,CX,INCX) * .. Scalar Arguments .. INTEGER INCX,N * .. * .. Array Arguments .. COMPLEX CX(*) * .. * * Purpose * ======= * * takes the sum of the absolute values of a complex vector and * returns a single precision result. * 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 STEMP INTEGER I,NINCX * .. * .. Intrinsic Functions .. INTRINSIC ABS,AIMAG,REAL * .. SCASUM = 0.0e0 STEMP = 0.0e0 IF (N.LE.0 .OR. INCX.LE.0) RETURN IF (INCX.EQ.1) GO TO 20 * * code for increment not equal to 1 * NINCX = N*INCX DO 10 I = 1,NINCX,INCX STEMP = STEMP + ABS(REAL(CX(I))) + ABS(AIMAG(CX(I))) 10 CONTINUE SCASUM = STEMP RETURN * * code for increment equal to 1 * 20 DO 30 I = 1,N STEMP = STEMP + ABS(REAL(CX(I))) + ABS(AIMAG(CX(I))) 30 CONTINUE SCASUM = STEMP RETURN END