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authorjason <jason@8a072113-8704-0410-8d35-dd094bca7971>2008-10-28 01:38:50 +0000
committerjason <jason@8a072113-8704-0410-8d35-dd094bca7971>2008-10-28 01:38:50 +0000
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Move LAPACK trunk into position.
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+ SUBROUTINE CLACRT( N, CX, INCX, CY, INCY, C, S )
+*
+* -- LAPACK auxiliary routine (version 3.1) --
+* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
+* November 2006
+*
+* .. Scalar Arguments ..
+ INTEGER INCX, INCY, N
+ COMPLEX C, S
+* ..
+* .. Array Arguments ..
+ COMPLEX CX( * ), CY( * )
+* ..
+*
+* Purpose
+* =======
+*
+* CLACRT performs the operation
+*
+* ( c s )( x ) ==> ( x )
+* ( -s c )( y ) ( y )
+*
+* where c and s are complex and the vectors x and y are complex.
+*
+* Arguments
+* =========
+*
+* N (input) INTEGER
+* The number of elements in the vectors CX and CY.
+*
+* CX (input/output) COMPLEX array, dimension (N)
+* On input, the vector x.
+* On output, CX is overwritten with c*x + s*y.
+*
+* INCX (input) INTEGER
+* The increment between successive values of CX. INCX <> 0.
+*
+* CY (input/output) COMPLEX array, dimension (N)
+* On input, the vector y.
+* On output, CY is overwritten with -s*x + c*y.
+*
+* INCY (input) INTEGER
+* The increment between successive values of CY. INCY <> 0.
+*
+* C (input) COMPLEX
+* S (input) COMPLEX
+* C and S define the matrix
+* [ C S ].
+* [ -S C ]
+*
+* =====================================================================
+*
+* .. Local Scalars ..
+ INTEGER I, IX, IY
+ COMPLEX CTEMP
+* ..
+* .. Executable Statements ..
+*
+ 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
+ CTEMP = C*CX( IX ) + S*CY( IY )
+ CY( IY ) = C*CY( IY ) - S*CX( IX )
+ CX( IX ) = CTEMP
+ IX = IX + INCX
+ IY = IY + INCY
+ 10 CONTINUE
+ RETURN
+*
+* Code for both increments equal to 1
+*
+ 20 CONTINUE
+ DO 30 I = 1, N
+ CTEMP = C*CX( I ) + S*CY( I )
+ CY( I ) = C*CY( I ) - S*CX( I )
+ CX( I ) = CTEMP
+ 30 CONTINUE
+ RETURN
+ END