comparison ext/clapack/src/dlaswp.c @ 430:335af74a25b6

Merge from branch clapack-included

+/* dlaswp.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 dlaswp_(integer *n, doublereal *a, integer *lda, integer 
+	*k1, integer *k2, integer *ipiv, integer *incx)
+{
+    /* System generated locals */
+    integer a_dim1, a_offset, i__1, i__2, i__3, i__4;
+
+    /* Local variables */
+    integer i__, j, k, i1, i2, n32, ip, ix, ix0, inc;
+    doublereal temp;
+
+
+/*  -- LAPACK auxiliary routine (version 3.2) -- */
+/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/*     November 2006 */
+
+/*     .. Scalar Arguments .. */
+/*     .. */
+/*     .. Array Arguments .. */
+/*     .. */
+
+/*  Purpose */
+/*  ======= */
+
+/*  DLASWP performs a series of row interchanges on the matrix A. */
+/*  One row interchange is initiated for each of rows K1 through K2 of A. */
+
+/*  Arguments */
+/*  ========= */
+
+/*  N       (input) INTEGER */
+/*          The number of columns of the matrix A. */
+
+/*  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N) */
+/*          On entry, the matrix of column dimension N to which the row */
+/*          interchanges will be applied. */
+/*          On exit, the permuted matrix. */
+
+/*  LDA     (input) INTEGER */
+/*          The leading dimension of the array A. */
+
+/*  K1      (input) INTEGER */
+/*          The first element of IPIV for which a row interchange will */
+/*          be done. */
+
+/*  K2      (input) INTEGER */
+/*          The last element of IPIV for which a row interchange will */
+/*          be done. */
+
+/*  IPIV    (input) INTEGER array, dimension (K2*abs(INCX)) */
+/*          The vector of pivot indices.  Only the elements in positions */
+/*          K1 through K2 of IPIV are accessed. */
+/*          IPIV(K) = L implies rows K and L are to be interchanged. */
+
+/*  INCX    (input) INTEGER */
+/*          The increment between successive values of IPIV.  If IPIV */
+/*          is negative, the pivots are applied in reverse order. */
+
+/*  Further Details */
+/*  =============== */
+
+/*  Modified by */
+/*   R. C. Whaley, Computer Science Dept., Univ. of Tenn., Knoxville, USA */
+
+/* ===================================================================== */
+
+/*     .. Local Scalars .. */
+/*     .. */
+/*     .. Executable Statements .. */
+
+/*     Interchange row I with row IPIV(I) for each of rows K1 through K2. */
+
+    /* Parameter adjustments */
+    a_dim1 = *lda;
+    a_offset = 1 + a_dim1;
+    a -= a_offset;
+    --ipiv;
+
+    /* Function Body */
+    if (*incx > 0) {
+	ix0 = *k1;
+	i1 = *k1;
+	i2 = *k2;
+	inc = 1;
+    } else if (*incx < 0) {
+	ix0 = (1 - *k2) * *incx + 1;
+	i1 = *k2;
+	i2 = *k1;
+	inc = -1;
+    } else {
+	return 0;
+    }
+
+    n32 = *n / 32 << 5;
+    if (n32 != 0) {
+	i__1 = n32;
+	for (j = 1; j <= i__1; j += 32) {
+	    ix = ix0;
+	    i__2 = i2;
+	    i__3 = inc;
+	    for (i__ = i1; i__3 < 0 ? i__ >= i__2 : i__ <= i__2; i__ += i__3) 
+		    {
+		ip = ipiv[ix];
+		if (ip != i__) {
+		    i__4 = j + 31;
+		    for (k = j; k <= i__4; ++k) {
+			temp = a[i__ + k * a_dim1];
+			a[i__ + k * a_dim1] = a[ip + k * a_dim1];
+			a[ip + k * a_dim1] = temp;
+/* L10: */
+		    }
+		}
+		ix += *incx;
+/* L20: */
+	    }
+/* L30: */
+	}
+    }
+    if (n32 != *n) {
+	++n32;
+	ix = ix0;
+	i__1 = i2;
+	i__3 = inc;
+	for (i__ = i1; i__3 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__3) {
+	    ip = ipiv[ix];
+	    if (ip != i__) {
+		i__2 = *n;
+		for (k = n32; k <= i__2; ++k) {
+		    temp = a[i__ + k * a_dim1];
+		    a[i__ + k * a_dim1] = a[ip + k * a_dim1];
+		    a[ip + k * a_dim1] = temp;
+/* L40: */
+		}
+	    }
+	    ix += *incx;
+/* L50: */
+	}
+    }
+
+    return 0;
+
+/*     End of DLASWP */
+
+} /* dlaswp_ */