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SUBROUTINE SROT(N,SX,INCX,SY,INCY,C,S)
* .. Scalar Arguments ..
REAL C,S
INTEGER INCX,INCY,N
* ..
* .. Array Arguments ..
REAL SX(*),SY(*)
* ..
*
* Purpose
* =======
*
* applies a plane rotation.
*
* Further Details
* ===============
*
* jack dongarra, linpack, 3/11/78.
* modified 12/3/93, array(1) declarations changed to array(*)
*
* =====================================================================
*
* .. Local Scalars ..
REAL STEMP
INTEGER I,IX,IY
* ..
IF (N.LE.0) 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
STEMP = C*SX(IX) + S*SY(IY)
SY(IY) = C*SY(IY) - S*SX(IX)
SX(IX) = STEMP
IX = IX + INCX
IY = IY + INCY
10 CONTINUE
RETURN
*
* code for both increments equal to 1
*
20 DO 30 I = 1,N
STEMP = C*SX(I) + S*SY(I)
SY(I) = C*SY(I) - S*SX(I)
SX(I) = STEMP
30 CONTINUE
RETURN
END
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