SUBROUTINE ZAXPY(N,ZA,ZX,INCX,ZY,INCY) * .. Scalar Arguments .. DOUBLE COMPLEX ZA INTEGER INCX,INCY,N * .. * .. Array Arguments .. DOUBLE COMPLEX ZX(*),ZY(*) * .. * * Purpose * ======= * * ZAXPY constant times a vector plus a vector. * * Further Details * =============== * * jack dongarra, 3/11/78. * modified 12/3/93, array(1) declarations changed to array(*) * * ===================================================================== * * .. Local Scalars .. INTEGER I,IX,IY * .. * .. External Functions .. DOUBLE PRECISION DCABS1 EXTERNAL DCABS1 * .. IF (N.LE.0) RETURN IF (DCABS1(ZA).EQ.0.0d0) RETURN IF (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20 * * code for unequal increments or equal increments * not equal to 1 * IX = 1 IY = 1 IF (INCX.LT.0) IX = (-N+1)*INCX + 1 IF (INCY.LT.0) IY = (-N+1)*INCY + 1 DO 10 I = 1,N ZY(IY) = ZY(IY) + ZA*ZX(IX) IX = IX + INCX IY = IY + INCY 10 CONTINUE RETURN * * code for both increments equal to 1 * 20 DO 30 I = 1,N ZY(I) = ZY(I) + ZA*ZX(I) 30 CONTINUE RETURN END