#include "blaswrap.h"
/* sort01.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"

/* Table of constant values */

static real c_b7 = 0.f;
static real c_b8 = 1.f;
static real c_b10 = -1.f;
static integer c__1 = 1;

/* Subroutine */ int sort01_(char *rowcol, integer *m, integer *n, real *u,  	integer *ldu, real *work, integer *lwork, real *resid  	)
{
    /* System generated locals */
    integer u_dim1, u_offset, i__1, i__2;
    real r__1, r__2;

    /* Local variables */
    static integer i__, j, k;
    static real eps, tmp;
    extern doublereal sdot_(integer *, real *, integer *, real *, integer *);
    extern logical lsame_(char *, char *);
    static integer mnmin;
    extern /* Subroutine */ int ssyrk_(char *, char *, integer *, integer *, 
	    real *, real *, integer *, real *, real *, integer *);
    extern doublereal slamch_(char *);
    extern /* Subroutine */ int slaset_(char *, integer *, integer *, real *, 
	    real *, real *, integer *);
    static integer ldwork;
    extern doublereal slansy_(char *, char *, integer *, real *, integer *, 
	    real *);
    static char transu[1];


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


    Purpose   
    =======   

    SORT01 checks that the matrix U is orthogonal by computing the ratio   

       RESID = norm( I - U*U' ) / ( n * EPS ), if ROWCOL = 'R',   
    or   
       RESID = norm( I - U'*U ) / ( m * EPS ), if ROWCOL = 'C'.   

    Alternatively, if there isn't sufficient workspace to form   
    I - U*U' or I - U'*U, the ratio is computed as   

       RESID = abs( I - U*U' ) / ( n * EPS ), if ROWCOL = 'R',   
    or   
       RESID = abs( I - U'*U ) / ( m * EPS ), if ROWCOL = 'C'.   

    where EPS is the machine precision.  ROWCOL is used only if m = n;   
    if m > n, ROWCOL is assumed to be 'C', and if m < n, ROWCOL is   
    assumed to be 'R'.   

    Arguments   
    =========   

    ROWCOL  (input) CHARACTER   
            Specifies whether the rows or columns of U should be checked   
            for orthogonality.  Used only if M = N.   
            = 'R':  Check for orthogonal rows of U   
            = 'C':  Check for orthogonal columns of U   

    M       (input) INTEGER   
            The number of rows of the matrix U.   

    N       (input) INTEGER   
            The number of columns of the matrix U.   

    U       (input) REAL array, dimension (LDU,N)   
            The orthogonal matrix U.  U is checked for orthogonal columns   
            if m > n or if m = n and ROWCOL = 'C'.  U is checked for   
            orthogonal rows if m < n or if m = n and ROWCOL = 'R'.   

    LDU     (input) INTEGER   
            The leading dimension of the array U.  LDU >= max(1,M).   

    WORK    (workspace) REAL array, dimension (LWORK)   

    LWORK   (input) INTEGER   
            The length of the array WORK.  For best performance, LWORK   
            should be at least N*(N+1) if ROWCOL = 'C' or M*(M+1) if   
            ROWCOL = 'R', but the test will be done even if LWORK is 0.   

    RESID   (output) REAL   
            RESID = norm( I - U * U' ) / ( n * EPS ), if ROWCOL = 'R', or   
            RESID = norm( I - U' * U ) / ( m * EPS ), if ROWCOL = 'C'.   

    =====================================================================   


       Parameter adjustments */
    u_dim1 = *ldu;
    u_offset = 1 + u_dim1;
    u -= u_offset;
    --work;

    /* Function Body */
    *resid = 0.f;

/*     Quick return if possible */

    if (*m <= 0 || *n <= 0) {
	return 0;
    }

    eps = slamch_("Precision");
    if (*m < *n || *m == *n && lsame_(rowcol, "R")) {
	*(unsigned char *)transu = 'N';
	k = *n;
    } else {
	*(unsigned char *)transu = 'T';
	k = *m;
    }
    mnmin = min(*m,*n);

    if ((mnmin + 1) * mnmin <= *lwork) {
	ldwork = mnmin;
    } else {
	ldwork = 0;
    }
    if (ldwork > 0) {

/*        Compute I - U*U' or I - U'*U. */

	slaset_("Upper", &mnmin, &mnmin, &c_b7, &c_b8, &work[1], &ldwork);
	ssyrk_("Upper", transu, &mnmin, &k, &c_b10, &u[u_offset], ldu, &c_b8, 
		&work[1], &ldwork);

/*        Compute norm( I - U*U' ) / ( K * EPS ) . */

	*resid = slansy_("1", "Upper", &mnmin, &work[1], &ldwork, &work[
		ldwork * mnmin + 1]);
	*resid = *resid / (real) k / eps;
    } else if (*(unsigned char *)transu == 'T') {

/*        Find the maximum element in abs( I - U'*U ) / ( m * EPS ) */

	i__1 = *n;
	for (j = 1; j <= i__1; ++j) {
	    i__2 = j;
	    for (i__ = 1; i__ <= i__2; ++i__) {
		if (i__ != j) {
		    tmp = 0.f;
		} else {
		    tmp = 1.f;
		}
		tmp -= sdot_(m, &u[i__ * u_dim1 + 1], &c__1, &u[j * u_dim1 + 
			1], &c__1);
/* Computing MAX */
		r__1 = *resid, r__2 = dabs(tmp);
		*resid = dmax(r__1,r__2);
/* L10: */
	    }
/* L20: */
	}
	*resid = *resid / (real) (*m) / eps;
    } else {

/*        Find the maximum element in abs( I - U*U' ) / ( n * EPS ) */

	i__1 = *m;
	for (j = 1; j <= i__1; ++j) {
	    i__2 = j;
	    for (i__ = 1; i__ <= i__2; ++i__) {
		if (i__ != j) {
		    tmp = 0.f;
		} else {
		    tmp = 1.f;
		}
		tmp -= sdot_(n, &u[j + u_dim1], ldu, &u[i__ + u_dim1], ldu);
/* Computing MAX */
		r__1 = *resid, r__2 = dabs(tmp);
		*resid = dmax(r__1,r__2);
/* L30: */
	    }
/* L40: */
	}
	*resid = *resid / (real) (*n) / eps;
    }
    return 0;

/*     End of SORT01 */

} /* sort01_ */