/* dlar2v.f -- translated by f2c (version 20061008). You must link the resulting object file with libf2c: on Microsoft Windows system, link with libf2c.lib; on Linux or Unix systems, link with .../path/to/libf2c.a -lm or, if you install libf2c.a in a standard place, with -lf2c -lm -- in that order, at the end of the command line, as in cc *.o -lf2c -lm Source for libf2c is in /netlib/f2c/libf2c.zip, e.g., http://www.netlib.org/f2c/libf2c.zip */ #include "f2c.h" #include "blaswrap.h" /* Subroutine */ int dlar2v_(integer *n, doublereal *x, doublereal *y, doublereal *z__, integer *incx, doublereal *c__, doublereal *s, integer *incc) { /* System generated locals */ integer i__1; /* Local variables */ integer i__; doublereal t1, t2, t3, t4, t5, t6; integer ic; doublereal ci, si; integer ix; doublereal xi, yi, zi; /* -- LAPACK auxiliary routine (version 3.2) -- */ /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ /* November 2006 */ /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* DLAR2V applies a vector of real plane rotations from both sides to */ /* a sequence of 2-by-2 real symmetric matrices, defined by the elements */ /* of the vectors x, y and z. For i = 1,2,...,n */ /* ( x(i) z(i) ) := ( c(i) s(i) ) ( x(i) z(i) ) ( c(i) -s(i) ) */ /* ( z(i) y(i) ) ( -s(i) c(i) ) ( z(i) y(i) ) ( s(i) c(i) ) */ /* Arguments */ /* ========= */ /* N (input) INTEGER */ /* The number of plane rotations to be applied. */ /* X (input/output) DOUBLE PRECISION array, */ /* dimension (1+(N-1)*INCX) */ /* The vector x. */ /* Y (input/output) DOUBLE PRECISION array, */ /* dimension (1+(N-1)*INCX) */ /* The vector y. */ /* Z (input/output) DOUBLE PRECISION array, */ /* dimension (1+(N-1)*INCX) */ /* The vector z. */ /* INCX (input) INTEGER */ /* The increment between elements of X, Y and Z. INCX > 0. */ /* C (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC) */ /* The cosines of the plane rotations. */ /* S (input) DOUBLE PRECISION array, dimension (1+(N-1)*INCC) */ /* The sines of the plane rotations. */ /* INCC (input) INTEGER */ /* The increment between elements of C and S. INCC > 0. */ /* ===================================================================== */ /* .. Local Scalars .. */ /* .. */ /* .. Executable Statements .. */ /* Parameter adjustments */ --s; --c__; --z__; --y; --x; /* Function Body */ ix = 1; ic = 1; i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { xi = x[ix]; yi = y[ix]; zi = z__[ix]; ci = c__[ic]; si = s[ic]; t1 = si * zi; t2 = ci * zi; t3 = t2 - si * xi; t4 = t2 + si * yi; t5 = ci * xi + t1; t6 = ci * yi - t1; x[ix] = ci * t5 + si * t4; y[ix] = ci * t6 - si * t3; z__[ix] = ci * t4 - si * t5; ix += *incx; ic += *incc; /* L10: */ } /* End of DLAR2V */ return 0; } /* dlar2v_ */