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SUBROUTINE ZDSCAL(N,DA,ZX,INCX)
* .. Scalar Arguments .. DOUBLE PRECISION DA INTEGER INCX,N * .. * .. Array Arguments .. DOUBLE COMPLEX ZX(*) * .. * * Purpose * ======= * * ZDSCAL scales a vector by a constant. * * Further Details * =============== * * jack dongarra, 3/11/78. * modified 3/93 to return if incx .le. 0. * modified 12/3/93, array(1) declarations changed to array(*) * * ===================================================================== * * .. Local Scalars .. INTEGER I,NINCX * .. * .. Intrinsic Functions .. INTRINSIC DCMPLX * .. IF (N.LE.0 .OR. INCX.LE.0) RETURN IF (INCX.EQ.1) THEN * * code for increment equal to 1 * DO I = 1,N ZX(I) = DCMPLX(DA,0.0d0)*ZX(I) END DO ELSE * * code for increment not equal to 1 * NINCX = N*INCX DO I = 1,NINCX,INCX ZX(I) = DCMPLX(DA,0.0d0)*ZX(I) END DO END IF RETURN END |