slaord.c

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/* slaord.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 slaord_(char *job, integer *n, real *x, integer *incx)
{
    /* System generated locals */
    integer i__1;

    /* Local variables */
    integer i__, ix, inc;
    real temp;
    extern logical lsame_(char *, char *);
    integer ixnext;


/*  -- LAPACK auxiliary routine (version 3.1) -- */
/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/*     November 2006 */

/*     .. Scalar Arguments .. */
/*     .. */
/*     .. Array Arguments .. */
/*     .. */

/*  Purpose */
/*  ======= */

/*  SLAORD sorts the elements of a vector x in increasing or decreasing */
/*  order. */

/*  Arguments */
/*  ========= */

/*  JOB     (input) CHARACTER */
/*          = 'I':  Sort in increasing order */
/*          = 'D':  Sort in decreasing order */

/*  N       (input) INTEGER */
/*          The length of the vector X. */

/*  X       (input/output) REAL array, dimension */
/*                         (1+(N-1)*INCX) */
/*          On entry, the vector of length n to be sorted. */
/*          On exit, the vector x is sorted in the prescribed order. */

/*  INCX    (input) INTEGER */
/*          The spacing between successive elements of X.  INCX >= 0. */

/*  ===================================================================== */

/*     .. Local Scalars .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. Intrinsic Functions .. */
/*     .. */
/*     .. Executable Statements .. */

    /* Parameter adjustments */
    --x;

    /* Function Body */
    inc = abs(*incx);
    if (lsame_(job, "I")) {

/*        Sort in increasing order */

        i__1 = *n;
        for (i__ = 2; i__ <= i__1; ++i__) {
            ix = (i__ - 1) * inc + 1;
L10:
            if (ix == 1) {
                goto L20;
            }
            ixnext = ix - inc;
            if (x[ix] > x[ixnext]) {
                goto L20;
            } else {
                temp = x[ix];
                x[ix] = x[ixnext];
                x[ixnext] = temp;
            }
            ix = ixnext;
            goto L10;
L20:
            ;
        }

    } else if (lsame_(job, "D")) {

/*        Sort in decreasing order */

        i__1 = *n;
        for (i__ = 2; i__ <= i__1; ++i__) {
            ix = (i__ - 1) * inc + 1;
L30:
            if (ix == 1) {
                goto L40;
            }
            ixnext = ix - inc;
            if (x[ix] < x[ixnext]) {
                goto L40;
            } else {
                temp = x[ix];
                x[ix] = x[ixnext];
                x[ixnext] = temp;
            }
            ix = ixnext;
            goto L30;
L40:
            ;
        }
    }
    return 0;

/*     End of SLAORD */

} /* slaord_ */