#include "blaswrap.h" #include "f2c.h" /* Subroutine */ int chemv_(char *uplo, integer *n, complex *alpha, complex * a, integer *lda, complex *x, integer *incx, complex *beta, complex *y, integer *incy) { /* System generated locals */ integer a_dim1, a_offset, i__1, i__2, i__3, i__4, i__5; real r__1; complex q__1, q__2, q__3, q__4; /* Builtin functions */ void r_cnjg(complex *, complex *); /* Local variables */ static integer i__, j, ix, iy, jx, jy, kx, ky, info; static complex temp1, temp2; extern logical lsame_(char *, char *); extern /* Subroutine */ int xerbla_(char *, integer *); /* Purpose ======= CHEMV performs the matrix-vector operation y := alpha*A*x + beta*y, where alpha and beta are scalars, x and y are n element vectors and A is an n by n hermitian matrix. Arguments ========== UPLO - CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of the array A is to be referenced as follows: UPLO = 'U' or 'u' Only the upper triangular part of A is to be referenced. UPLO = 'L' or 'l' Only the lower triangular part of A is to be referenced. Unchanged on exit. N - INTEGER. On entry, N specifies the order of the matrix A. N must be at least zero. Unchanged on exit. ALPHA - COMPLEX . On entry, ALPHA specifies the scalar alpha. Unchanged on exit. A - COMPLEX array of DIMENSION ( LDA, n ). Before entry with UPLO = 'U' or 'u', the leading n by n upper triangular part of the array A must contain the upper triangular part of the hermitian matrix and the strictly lower triangular part of A is not referenced. Before entry with UPLO = 'L' or 'l', the leading n by n lower triangular part of the array A must contain the lower triangular part of the hermitian matrix and the strictly upper triangular part of A is not referenced. Note that the imaginary parts of the diagonal elements need not be set and are assumed to be zero. Unchanged on exit. LDA - INTEGER. On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA must be at least max( 1, n ). Unchanged on exit. X - COMPLEX array of dimension at least ( 1 + ( n - 1 )*abs( INCX ) ). Before entry, the incremented array X must contain the n element vector x. Unchanged on exit. INCX - INTEGER. On entry, INCX specifies the increment for the elements of X. INCX must not be zero. Unchanged on exit. BETA - COMPLEX . On entry, BETA specifies the scalar beta. When BETA is supplied as zero then Y need not be set on input. Unchanged on exit. Y - COMPLEX array of dimension at least ( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the n element vector y. On exit, Y is overwritten by the updated vector y. INCY - INTEGER. On entry, INCY specifies the increment for the elements of Y. INCY must not be zero. Unchanged on exit. Level 2 Blas routine. -- Written on 22-October-1986. Jack Dongarra, Argonne National Lab. Jeremy Du Croz, Nag Central Office. Sven Hammarling, Nag Central Office. Richard Hanson, Sandia National Labs. Test the input parameters. Parameter adjustments */ a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; --x; --y; /* Function Body */ info = 0; if (! lsame_(uplo, "U") && ! lsame_(uplo, "L")) { info = 1; } else if (*n < 0) { info = 2; } else if (*lda < max(1,*n)) { info = 5; } else if (*incx == 0) { info = 7; } else if (*incy == 0) { info = 10; } if (info != 0) { xerbla_("CHEMV ", &info); return 0; } /* Quick return if possible. */ if (*n == 0 || alpha->r == 0.f && alpha->i == 0.f && (beta->r == 1.f && beta->i == 0.f)) { return 0; } /* Set up the start points in X and Y. */ if (*incx > 0) { kx = 1; } else { kx = 1 - (*n - 1) * *incx; } if (*incy > 0) { ky = 1; } else { ky = 1 - (*n - 1) * *incy; } /* Start the operations. In this version the elements of A are accessed sequentially with one pass through the triangular part of A. First form y := beta*y. */ if (beta->r != 1.f || beta->i != 0.f) { if (*incy == 1) { if (beta->r == 0.f && beta->i == 0.f) { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; y[i__2].r = 0.f, y[i__2].i = 0.f; /* L10: */ } } else { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = i__; i__3 = i__; q__1.r = beta->r * y[i__3].r - beta->i * y[i__3].i, q__1.i = beta->r * y[i__3].i + beta->i * y[i__3] .r; y[i__2].r = q__1.r, y[i__2].i = q__1.i; /* L20: */ } } } else { iy = ky; if (beta->r == 0.f && beta->i == 0.f) { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = iy; y[i__2].r = 0.f, y[i__2].i = 0.f; iy += *incy; /* L30: */ } } else { i__1 = *n; for (i__ = 1; i__ <= i__1; ++i__) { i__2 = iy; i__3 = iy; q__1.r = beta->r * y[i__3].r - beta->i * y[i__3].i, q__1.i = beta->r * y[i__3].i + beta->i * y[i__3] .r; y[i__2].r = q__1.r, y[i__2].i = q__1.i; iy += *incy; /* L40: */ } } } } if (alpha->r == 0.f && alpha->i == 0.f) { return 0; } if (lsame_(uplo, "U")) { /* Form y when A is stored in upper triangle. */ if (*incx == 1 && *incy == 1) { i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = j; q__1.r = alpha->r * x[i__2].r - alpha->i * x[i__2].i, q__1.i = alpha->r * x[i__2].i + alpha->i * x[i__2].r; temp1.r = q__1.r, temp1.i = q__1.i; temp2.r = 0.f, temp2.i = 0.f; i__2 = j - 1; for (i__ = 1; i__ <= i__2; ++i__) { i__3 = i__; i__4 = i__; i__5 = i__ + j * a_dim1; q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5] .r; q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i; y[i__3].r = q__1.r, y[i__3].i = q__1.i; r_cnjg(&q__3, &a[i__ + j * a_dim1]); i__3 = i__; q__2.r = q__3.r * x[i__3].r - q__3.i * x[i__3].i, q__2.i = q__3.r * x[i__3].i + q__3.i * x[i__3].r; q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i; temp2.r = q__1.r, temp2.i = q__1.i; /* L50: */ } i__2 = j; i__3 = j; i__4 = j + j * a_dim1; r__1 = a[i__4].r; q__3.r = r__1 * temp1.r, q__3.i = r__1 * temp1.i; q__2.r = y[i__3].r + q__3.r, q__2.i = y[i__3].i + q__3.i; q__4.r = alpha->r * temp2.r - alpha->i * temp2.i, q__4.i = alpha->r * temp2.i + alpha->i * temp2.r; q__1.r = q__2.r + q__4.r, q__1.i = q__2.i + q__4.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; /* L60: */ } } else { jx = kx; jy = ky; i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = jx; q__1.r = alpha->r * x[i__2].r - alpha->i * x[i__2].i, q__1.i = alpha->r * x[i__2].i + alpha->i * x[i__2].r; temp1.r = q__1.r, temp1.i = q__1.i; temp2.r = 0.f, temp2.i = 0.f; ix = kx; iy = ky; i__2 = j - 1; for (i__ = 1; i__ <= i__2; ++i__) { i__3 = iy; i__4 = iy; i__5 = i__ + j * a_dim1; q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5] .r; q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i; y[i__3].r = q__1.r, y[i__3].i = q__1.i; r_cnjg(&q__3, &a[i__ + j * a_dim1]); i__3 = ix; q__2.r = q__3.r * x[i__3].r - q__3.i * x[i__3].i, q__2.i = q__3.r * x[i__3].i + q__3.i * x[i__3].r; q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i; temp2.r = q__1.r, temp2.i = q__1.i; ix += *incx; iy += *incy; /* L70: */ } i__2 = jy; i__3 = jy; i__4 = j + j * a_dim1; r__1 = a[i__4].r; q__3.r = r__1 * temp1.r, q__3.i = r__1 * temp1.i; q__2.r = y[i__3].r + q__3.r, q__2.i = y[i__3].i + q__3.i; q__4.r = alpha->r * temp2.r - alpha->i * temp2.i, q__4.i = alpha->r * temp2.i + alpha->i * temp2.r; q__1.r = q__2.r + q__4.r, q__1.i = q__2.i + q__4.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; jx += *incx; jy += *incy; /* L80: */ } } } else { /* Form y when A is stored in lower triangle. */ if (*incx == 1 && *incy == 1) { i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = j; q__1.r = alpha->r * x[i__2].r - alpha->i * x[i__2].i, q__1.i = alpha->r * x[i__2].i + alpha->i * x[i__2].r; temp1.r = q__1.r, temp1.i = q__1.i; temp2.r = 0.f, temp2.i = 0.f; i__2 = j; i__3 = j; i__4 = j + j * a_dim1; r__1 = a[i__4].r; q__2.r = r__1 * temp1.r, q__2.i = r__1 * temp1.i; q__1.r = y[i__3].r + q__2.r, q__1.i = y[i__3].i + q__2.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; i__2 = *n; for (i__ = j + 1; i__ <= i__2; ++i__) { i__3 = i__; i__4 = i__; i__5 = i__ + j * a_dim1; q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5] .r; q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i; y[i__3].r = q__1.r, y[i__3].i = q__1.i; r_cnjg(&q__3, &a[i__ + j * a_dim1]); i__3 = i__; q__2.r = q__3.r * x[i__3].r - q__3.i * x[i__3].i, q__2.i = q__3.r * x[i__3].i + q__3.i * x[i__3].r; q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i; temp2.r = q__1.r, temp2.i = q__1.i; /* L90: */ } i__2 = j; i__3 = j; q__2.r = alpha->r * temp2.r - alpha->i * temp2.i, q__2.i = alpha->r * temp2.i + alpha->i * temp2.r; q__1.r = y[i__3].r + q__2.r, q__1.i = y[i__3].i + q__2.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; /* L100: */ } } else { jx = kx; jy = ky; i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = jx; q__1.r = alpha->r * x[i__2].r - alpha->i * x[i__2].i, q__1.i = alpha->r * x[i__2].i + alpha->i * x[i__2].r; temp1.r = q__1.r, temp1.i = q__1.i; temp2.r = 0.f, temp2.i = 0.f; i__2 = jy; i__3 = jy; i__4 = j + j * a_dim1; r__1 = a[i__4].r; q__2.r = r__1 * temp1.r, q__2.i = r__1 * temp1.i; q__1.r = y[i__3].r + q__2.r, q__1.i = y[i__3].i + q__2.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; ix = jx; iy = jy; i__2 = *n; for (i__ = j + 1; i__ <= i__2; ++i__) { ix += *incx; iy += *incy; i__3 = iy; i__4 = iy; i__5 = i__ + j * a_dim1; q__2.r = temp1.r * a[i__5].r - temp1.i * a[i__5].i, q__2.i = temp1.r * a[i__5].i + temp1.i * a[i__5] .r; q__1.r = y[i__4].r + q__2.r, q__1.i = y[i__4].i + q__2.i; y[i__3].r = q__1.r, y[i__3].i = q__1.i; r_cnjg(&q__3, &a[i__ + j * a_dim1]); i__3 = ix; q__2.r = q__3.r * x[i__3].r - q__3.i * x[i__3].i, q__2.i = q__3.r * x[i__3].i + q__3.i * x[i__3].r; q__1.r = temp2.r + q__2.r, q__1.i = temp2.i + q__2.i; temp2.r = q__1.r, temp2.i = q__1.i; /* L110: */ } i__2 = jy; i__3 = jy; q__2.r = alpha->r * temp2.r - alpha->i * temp2.i, q__2.i = alpha->r * temp2.i + alpha->i * temp2.r; q__1.r = y[i__3].r + q__2.r, q__1.i = y[i__3].i + q__2.i; y[i__2].r = q__1.r, y[i__2].i = q__1.i; jx += *incx; jy += *incy; /* L120: */ } } } return 0; /* End of CHEMV . */ } /* chemv_ */