00001 SUBROUTINE SLARTV( N, X, INCX, Y, INCY, C, S, INCC ) 00002 * 00003 * -- LAPACK auxiliary routine (version 3.2) -- 00004 * -- LAPACK is a software package provided by Univ. of Tennessee, -- 00005 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 00006 * November 2006 00007 * 00008 * .. Scalar Arguments .. 00009 INTEGER INCC, INCX, INCY, N 00010 * .. 00011 * .. Array Arguments .. 00012 REAL C( * ), S( * ), X( * ), Y( * ) 00013 * .. 00014 * 00015 * Purpose 00016 * ======= 00017 * 00018 * SLARTV applies a vector of real plane rotations to elements of the 00019 * real vectors x and y. For i = 1,2,...,n 00020 * 00021 * ( x(i) ) := ( c(i) s(i) ) ( x(i) ) 00022 * ( y(i) ) ( -s(i) c(i) ) ( y(i) ) 00023 * 00024 * Arguments 00025 * ========= 00026 * 00027 * N (input) INTEGER 00028 * The number of plane rotations to be applied. 00029 * 00030 * X (input/output) REAL array, 00031 * dimension (1+(N-1)*INCX) 00032 * The vector x. 00033 * 00034 * INCX (input) INTEGER 00035 * The increment between elements of X. INCX > 0. 00036 * 00037 * Y (input/output) REAL array, 00038 * dimension (1+(N-1)*INCY) 00039 * The vector y. 00040 * 00041 * INCY (input) INTEGER 00042 * The increment between elements of Y. INCY > 0. 00043 * 00044 * C (input) REAL array, dimension (1+(N-1)*INCC) 00045 * The cosines of the plane rotations. 00046 * 00047 * S (input) REAL array, dimension (1+(N-1)*INCC) 00048 * The sines of the plane rotations. 00049 * 00050 * INCC (input) INTEGER 00051 * The increment between elements of C and S. INCC > 0. 00052 * 00053 * ===================================================================== 00054 * 00055 * .. Local Scalars .. 00056 INTEGER I, IC, IX, IY 00057 REAL XI, YI 00058 * .. 00059 * .. Executable Statements .. 00060 * 00061 IX = 1 00062 IY = 1 00063 IC = 1 00064 DO 10 I = 1, N 00065 XI = X( IX ) 00066 YI = Y( IY ) 00067 X( IX ) = C( IC )*XI + S( IC )*YI 00068 Y( IY ) = C( IC )*YI - S( IC )*XI 00069 IX = IX + INCX 00070 IY = IY + INCY 00071 IC = IC + INCC 00072 10 CONTINUE 00073 RETURN 00074 * 00075 * End of SLARTV 00076 * 00077 END
1.7.2