OpenBLAS/lapack-netlib/SRC/zsptri.c

/* f2c.h  --  Standard Fortran to C header file */

/**  barf  [ba:rf]  2.  "He suggested using FORTRAN, and everybody barfed."

	- From The Shogakukan DICTIONARY OF NEW ENGLISH (Second edition) */

#ifndef F2C_INCLUDE
#define F2C_INCLUDE

#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <complex.h>
#ifdef complex
#undef complex
#endif
#ifdef I
#undef I
#endif

#if defined(_WIN64)
typedef long long BLASLONG;
typedef unsigned long long BLASULONG;
#else
typedef long BLASLONG;
typedef unsigned long BLASULONG;
#endif

#ifdef LAPACK_ILP64
typedef BLASLONG blasint;
#if defined(_WIN64)
#define blasabs(x) llabs(x)
#else
#define blasabs(x) labs(x)
#endif
#else
typedef int blasint;
#define blasabs(x) abs(x)
#endif

typedef blasint integer;

typedef unsigned int uinteger;
typedef char *address;
typedef short int shortint;
typedef float real;
typedef double doublereal;
typedef struct { real r, i; } complex;
typedef struct { doublereal r, i; } doublecomplex;
static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
#define pCf(z) (*_pCf(z))
#define pCd(z) (*_pCd(z))
typedef int logical;
typedef short int shortlogical;
typedef char logical1;
typedef char integer1;

#define TRUE_ (1)
#define FALSE_ (0)

/* Extern is for use with -E */
#ifndef Extern
#define Extern extern
#endif

/* I/O stuff */

typedef int flag;
typedef int ftnlen;
typedef int ftnint;

/*external read, write*/
typedef struct
{	flag cierr;
	ftnint ciunit;
	flag ciend;
	char *cifmt;
	ftnint cirec;
} cilist;

/*internal read, write*/
typedef struct
{	flag icierr;
	char *iciunit;
	flag iciend;
	char *icifmt;
	ftnint icirlen;
	ftnint icirnum;
} icilist;

/*open*/
typedef struct
{	flag oerr;
	ftnint ounit;
	char *ofnm;
	ftnlen ofnmlen;
	char *osta;
	char *oacc;
	char *ofm;
	ftnint orl;
	char *oblnk;
} olist;

/*close*/
typedef struct
{	flag cerr;
	ftnint cunit;
	char *csta;
} cllist;

/*rewind, backspace, endfile*/
typedef struct
{	flag aerr;
	ftnint aunit;
} alist;

/* inquire */
typedef struct
{	flag inerr;
	ftnint inunit;
	char *infile;
	ftnlen infilen;
	ftnint	*inex;	/*parameters in standard's order*/
	ftnint	*inopen;
	ftnint	*innum;
	ftnint	*innamed;
	char	*inname;
	ftnlen	innamlen;
	char	*inacc;
	ftnlen	inacclen;
	char	*inseq;
	ftnlen	inseqlen;
	char 	*indir;
	ftnlen	indirlen;
	char	*infmt;
	ftnlen	infmtlen;
	char	*inform;
	ftnint	informlen;
	char	*inunf;
	ftnlen	inunflen;
	ftnint	*inrecl;
	ftnint	*innrec;
	char	*inblank;
	ftnlen	inblanklen;
} inlist;

#define VOID void

union Multitype {	/* for multiple entry points */
	integer1 g;
	shortint h;
	integer i;
	/* longint j; */
	real r;
	doublereal d;
	complex c;
	doublecomplex z;
	};

typedef union Multitype Multitype;

struct Vardesc {	/* for Namelist */
	char *name;
	char *addr;
	ftnlen *dims;
	int  type;
	};
typedef struct Vardesc Vardesc;

struct Namelist {
	char *name;
	Vardesc **vars;
	int nvars;
	};
typedef struct Namelist Namelist;

#define abs(x) ((x) >= 0 ? (x) : -(x))
#define dabs(x) (fabs(x))
#define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
#define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
#define dmin(a,b) (f2cmin(a,b))
#define dmax(a,b) (f2cmax(a,b))
#define bit_test(a,b)	((a) >> (b) & 1)
#define bit_clear(a,b)	((a) & ~((uinteger)1 << (b)))
#define bit_set(a,b)	((a) |  ((uinteger)1 << (b)))

#define abort_() { sig_die("Fortran abort routine called", 1); }
#define c_abs(z) (cabsf(Cf(z)))
#define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
#define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
#define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
#define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
#define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
#define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
//#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
#define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
#define d_abs(x) (fabs(*(x)))
#define d_acos(x) (acos(*(x)))
#define d_asin(x) (asin(*(x)))
#define d_atan(x) (atan(*(x)))
#define d_atn2(x, y) (atan2(*(x),*(y)))
#define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
#define r_cnjg(R, Z) { pCf(R) = conj(Cf(Z)); }
#define d_cos(x) (cos(*(x)))
#define d_cosh(x) (cosh(*(x)))
#define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
#define d_exp(x) (exp(*(x)))
#define d_imag(z) (cimag(Cd(z)))
#define r_imag(z) (cimag(Cf(z)))
#define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
#define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
#define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
#define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
#define d_log(x) (log(*(x)))
#define d_mod(x, y) (fmod(*(x), *(y)))
#define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
#define d_nint(x) u_nint(*(x))
#define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
#define d_sign(a,b) u_sign(*(a),*(b))
#define r_sign(a,b) u_sign(*(a),*(b))
#define d_sin(x) (sin(*(x)))
#define d_sinh(x) (sinh(*(x)))
#define d_sqrt(x) (sqrt(*(x)))
#define d_tan(x) (tan(*(x)))
#define d_tanh(x) (tanh(*(x)))
#define i_abs(x) abs(*(x))
#define i_dnnt(x) ((integer)u_nint(*(x)))
#define i_len(s, n) (n)
#define i_nint(x) ((integer)u_nint(*(x)))
#define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
#define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
#define pow_si(B,E) spow_ui(*(B),*(E))
#define pow_ri(B,E) spow_ui(*(B),*(E))
#define pow_di(B,E) dpow_ui(*(B),*(E))
#define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
#define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
#define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
#define s_cat(lpp, rpp, rnp, np, llp) { 	ftnlen i, nc, ll; char *f__rp, *lp; 	ll = (llp); lp = (lpp); 	for(i=0; i < (int)*(np); ++i) {         	nc = ll; 	        if((rnp)[i] < nc) nc = (rnp)[i]; 	        ll -= nc;         	f__rp = (rpp)[i]; 	        while(--nc >= 0) *lp++ = *(f__rp)++;         } 	while(--ll >= 0) *lp++ = ' '; }
#define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
#define s_copy(A,B,C,D) { int __i,__m; for (__i=0, __m=f2cmin((C),(D)); __i<__m && (B)[__i] != 0; ++__i) (A)[__i] = (B)[__i]; }
#define sig_die(s, kill) { exit(1); }
#define s_stop(s, n) {exit(0);}
static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
#define z_abs(z) (cabs(Cd(z)))
#define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
#define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
#define myexit_() break;
#define mycycle() continue;
#define myceiling(w) {ceil(w)}
#define myhuge(w) {HUGE_VAL}
//#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
#define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}

/* procedure parameter types for -A and -C++ */

#define F2C_proc_par_types 1
#ifdef __cplusplus
typedef logical (*L_fp)(...);
#else
typedef logical (*L_fp)();
#endif

static float spow_ui(float x, integer n) {
	float pow=1.0; unsigned long int u;
	if(n != 0) {
		if(n < 0) n = -n, x = 1/x;
		for(u = n; ; ) {
			if(u & 01) pow *= x;
			if(u >>= 1) x *= x;
			else break;
		}
	}
	return pow;
}
static double dpow_ui(double x, integer n) {
	double pow=1.0; unsigned long int u;
	if(n != 0) {
		if(n < 0) n = -n, x = 1/x;
		for(u = n; ; ) {
			if(u & 01) pow *= x;
			if(u >>= 1) x *= x;
			else break;
		}
	}
	return pow;
}
static _Complex float cpow_ui(_Complex float x, integer n) {
	_Complex float pow=1.0; unsigned long int u;
	if(n != 0) {
		if(n < 0) n = -n, x = 1/x;
		for(u = n; ; ) {
			if(u & 01) pow *= x;
			if(u >>= 1) x *= x;
			else break;
		}
	}
	return pow;
}
static _Complex double zpow_ui(_Complex double x, integer n) {
	_Complex double pow=1.0; unsigned long int u;
	if(n != 0) {
		if(n < 0) n = -n, x = 1/x;
		for(u = n; ; ) {
			if(u & 01) pow *= x;
			if(u >>= 1) x *= x;
			else break;
		}
	}
	return pow;
}
static integer pow_ii(integer x, integer n) {
	integer pow; unsigned long int u;
	if (n <= 0) {
		if (n == 0 || x == 1) pow = 1;
		else if (x != -1) pow = x == 0 ? 1/x : 0;
		else n = -n;
	}
	if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
		u = n;
		for(pow = 1; ; ) {
			if(u & 01) pow *= x;
			if(u >>= 1) x *= x;
			else break;
		}
	}
	return pow;
}
static integer dmaxloc_(double *w, integer s, integer e, integer *n)
{
	double m; integer i, mi;
	for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
		if (w[i-1]>m) mi=i ,m=w[i-1];
	return mi-s+1;
}
static integer smaxloc_(float *w, integer s, integer e, integer *n)
{
	float m; integer i, mi;
	for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
		if (w[i-1]>m) mi=i ,m=w[i-1];
	return mi-s+1;
}
static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
	integer n = *n_, incx = *incx_, incy = *incy_, i;
	_Complex float zdotc = 0.0;
	if (incx == 1 && incy == 1) {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
		}
	} else {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
		}
	}
	pCf(z) = zdotc;
}
static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
	integer n = *n_, incx = *incx_, incy = *incy_, i;
	_Complex double zdotc = 0.0;
	if (incx == 1 && incy == 1) {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
		}
	} else {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
		}
	}
	pCd(z) = zdotc;
}	
static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
	integer n = *n_, incx = *incx_, incy = *incy_, i;
	_Complex float zdotc = 0.0;
	if (incx == 1 && incy == 1) {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += Cf(&x[i]) * Cf(&y[i]);
		}
	} else {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
		}
	}
	pCf(z) = zdotc;
}
static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
	integer n = *n_, incx = *incx_, incy = *incy_, i;
	_Complex double zdotc = 0.0;
	if (incx == 1 && incy == 1) {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += Cd(&x[i]) * Cd(&y[i]);
		}
	} else {
		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
			zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
		}
	}
	pCd(z) = zdotc;
}
#endif
/*  -- translated by f2c (version 20000121).
   You must link the resulting object file with the libraries:
	-lf2c -lm   (in that order)
*/



/* Table of constant values */

static doublecomplex c_b1 = {1.,0.};
static doublecomplex c_b2 = {0.,0.};
static integer c__1 = 1;

/* > \brief \b ZSPTRI */

/*  =========== DOCUMENTATION =========== */

/* Online html documentation available at */
/*            http://www.netlib.org/lapack/explore-html/ */

/* > \htmlonly */
/* > Download ZSPTRI + dependencies */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zsptri.
f"> */
/* > [TGZ]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zsptri.
f"> */
/* > [ZIP]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zsptri.
f"> */
/* > [TXT]</a> */
/* > \endhtmlonly */

/*  Definition: */
/*  =========== */

/*       SUBROUTINE ZSPTRI( UPLO, N, AP, IPIV, WORK, INFO ) */

/*       CHARACTER          UPLO */
/*       INTEGER            INFO, N */
/*       INTEGER            IPIV( * ) */
/*       COMPLEX*16         AP( * ), WORK( * ) */


/* > \par Purpose: */
/*  ============= */
/* > */
/* > \verbatim */
/* > */
/* > ZSPTRI computes the inverse of a complex symmetric indefinite matrix */
/* > A in packed storage using the factorization A = U*D*U**T or */
/* > A = L*D*L**T computed by ZSPTRF. */
/* > \endverbatim */

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

/* > \param[in] UPLO */
/* > \verbatim */
/* >          UPLO is CHARACTER*1 */
/* >          Specifies whether the details of the factorization are stored */
/* >          as an upper or lower triangular matrix. */
/* >          = 'U':  Upper triangular, form is A = U*D*U**T; */
/* >          = 'L':  Lower triangular, form is A = L*D*L**T. */
/* > \endverbatim */
/* > */
/* > \param[in] N */
/* > \verbatim */
/* >          N is INTEGER */
/* >          The order of the matrix A.  N >= 0. */
/* > \endverbatim */
/* > */
/* > \param[in,out] AP */
/* > \verbatim */
/* >          AP is COMPLEX*16 array, dimension (N*(N+1)/2) */
/* >          On entry, the block diagonal matrix D and the multipliers */
/* >          used to obtain the factor U or L as computed by ZSPTRF, */
/* >          stored as a packed triangular matrix. */
/* > */
/* >          On exit, if INFO = 0, the (symmetric) inverse of the original */
/* >          matrix, stored as a packed triangular matrix. The j-th column */
/* >          of inv(A) is stored in the array AP as follows: */
/* >          if UPLO = 'U', AP(i + (j-1)*j/2) = inv(A)(i,j) for 1<=i<=j; */
/* >          if UPLO = 'L', */
/* >             AP(i + (j-1)*(2n-j)/2) = inv(A)(i,j) for j<=i<=n. */
/* > \endverbatim */
/* > */
/* > \param[in] IPIV */
/* > \verbatim */
/* >          IPIV is INTEGER array, dimension (N) */
/* >          Details of the interchanges and the block structure of D */
/* >          as determined by ZSPTRF. */
/* > \endverbatim */
/* > */
/* > \param[out] WORK */
/* > \verbatim */
/* >          WORK is COMPLEX*16 array, dimension (N) */
/* > \endverbatim */
/* > */
/* > \param[out] INFO */
/* > \verbatim */
/* >          INFO is INTEGER */
/* >          = 0: successful exit */
/* >          < 0: if INFO = -i, the i-th argument had an illegal value */
/* >          > 0: if INFO = i, D(i,i) = 0; the matrix is singular and its */
/* >               inverse could not be computed. */
/* > \endverbatim */

/*  Authors: */
/*  ======== */

/* > \author Univ. of Tennessee */
/* > \author Univ. of California Berkeley */
/* > \author Univ. of Colorado Denver */
/* > \author NAG Ltd. */

/* > \date December 2016 */

/* > \ingroup complex16OTHERcomputational */

/*  ===================================================================== */
/* Subroutine */ int zsptri_(char *uplo, integer *n, doublecomplex *ap, 
	integer *ipiv, doublecomplex *work, integer *info)
{
    /* System generated locals */
    integer i__1, i__2, i__3;
    doublecomplex z__1, z__2, z__3;

    /* Local variables */
    doublecomplex temp, akkp1, d__;
    integer j, k;
    doublecomplex t;
    extern logical lsame_(char *, char *);
    integer kstep;
    logical upper;
    extern /* Subroutine */ int zcopy_(integer *, doublecomplex *, integer *, 
	    doublecomplex *, integer *);
    extern /* Double Complex */ VOID zdotu_(doublecomplex *, integer *, 
	    doublecomplex *, integer *, doublecomplex *, integer *);
    extern /* Subroutine */ int zswap_(integer *, doublecomplex *, integer *, 
	    doublecomplex *, integer *), zspmv_(char *, integer *, 
	    doublecomplex *, doublecomplex *, doublecomplex *, integer *, 
	    doublecomplex *, doublecomplex *, integer *);
    doublecomplex ak;
    integer kc, kp, kx;
    extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
    integer kcnext, kpc, npp;
    doublecomplex akp1;


/*  -- LAPACK computational routine (version 3.7.0) -- */
/*  -- LAPACK is a software package provided by Univ. of Tennessee,    -- */
/*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/*     December 2016 */


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


/*     Test the input parameters. */

    /* Parameter adjustments */
    --work;
    --ipiv;
    --ap;

    /* Function Body */
    *info = 0;
    upper = lsame_(uplo, "U");
    if (! upper && ! lsame_(uplo, "L")) {
	*info = -1;
    } else if (*n < 0) {
	*info = -2;
    }
    if (*info != 0) {
	i__1 = -(*info);
	xerbla_("ZSPTRI", &i__1, (ftnlen)6);
	return 0;
    }

/*     Quick return if possible */

    if (*n == 0) {
	return 0;
    }

/*     Check that the diagonal matrix D is nonsingular. */

    if (upper) {

/*        Upper triangular storage: examine D from bottom to top */

	kp = *n * (*n + 1) / 2;
	for (*info = *n; *info >= 1; --(*info)) {
	    i__1 = kp;
	    if (ipiv[*info] > 0 && (ap[i__1].r == 0. && ap[i__1].i == 0.)) {
		return 0;
	    }
	    kp -= *info;
/* L10: */
	}
    } else {

/*        Lower triangular storage: examine D from top to bottom. */

	kp = 1;
	i__1 = *n;
	for (*info = 1; *info <= i__1; ++(*info)) {
	    i__2 = kp;
	    if (ipiv[*info] > 0 && (ap[i__2].r == 0. && ap[i__2].i == 0.)) {
		return 0;
	    }
	    kp = kp + *n - *info + 1;
/* L20: */
	}
    }
    *info = 0;

    if (upper) {

/*        Compute inv(A) from the factorization A = U*D*U**T. */

/*        K is the main loop index, increasing from 1 to N in steps of */
/*        1 or 2, depending on the size of the diagonal blocks. */

	k = 1;
	kc = 1;
L30:

/*        If K > N, exit from loop. */

	if (k > *n) {
	    goto L50;
	}

	kcnext = kc + k;
	if (ipiv[k] > 0) {

/*           1 x 1 diagonal block */

/*           Invert the diagonal block. */

	    i__1 = kc + k - 1;
	    z_div(&z__1, &c_b1, &ap[kc + k - 1]);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;

/*           Compute column K of the inverse. */

	    if (k > 1) {
		i__1 = k - 1;
		zcopy_(&i__1, &ap[kc], &c__1, &work[1], &c__1);
		i__1 = k - 1;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[1], &work[1], &c__1, &c_b2, &
			ap[kc], &c__1);
		i__1 = kc + k - 1;
		i__2 = kc + k - 1;
		i__3 = k - 1;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kc], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    }
	    kstep = 1;
	} else {

/*           2 x 2 diagonal block */

/*           Invert the diagonal block. */

	    i__1 = kcnext + k - 1;
	    t.r = ap[i__1].r, t.i = ap[i__1].i;
	    z_div(&z__1, &ap[kc + k - 1], &t);
	    ak.r = z__1.r, ak.i = z__1.i;
	    z_div(&z__1, &ap[kcnext + k], &t);
	    akp1.r = z__1.r, akp1.i = z__1.i;
	    z_div(&z__1, &ap[kcnext + k - 1], &t);
	    akkp1.r = z__1.r, akkp1.i = z__1.i;
	    z__3.r = ak.r * akp1.r - ak.i * akp1.i, z__3.i = ak.r * akp1.i + 
		    ak.i * akp1.r;
	    z__2.r = z__3.r - 1., z__2.i = z__3.i + 0.;
	    z__1.r = t.r * z__2.r - t.i * z__2.i, z__1.i = t.r * z__2.i + t.i 
		    * z__2.r;
	    d__.r = z__1.r, d__.i = z__1.i;
	    i__1 = kc + k - 1;
	    z_div(&z__1, &akp1, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    i__1 = kcnext + k;
	    z_div(&z__1, &ak, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    i__1 = kcnext + k - 1;
	    z__2.r = -akkp1.r, z__2.i = -akkp1.i;
	    z_div(&z__1, &z__2, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;

/*           Compute columns K and K+1 of the inverse. */

	    if (k > 1) {
		i__1 = k - 1;
		zcopy_(&i__1, &ap[kc], &c__1, &work[1], &c__1);
		i__1 = k - 1;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[1], &work[1], &c__1, &c_b2, &
			ap[kc], &c__1);
		i__1 = kc + k - 1;
		i__2 = kc + k - 1;
		i__3 = k - 1;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kc], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
		i__1 = kcnext + k - 1;
		i__2 = kcnext + k - 1;
		i__3 = k - 1;
		zdotu_(&z__2, &i__3, &ap[kc], &c__1, &ap[kcnext], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
		i__1 = k - 1;
		zcopy_(&i__1, &ap[kcnext], &c__1, &work[1], &c__1);
		i__1 = k - 1;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[1], &work[1], &c__1, &c_b2, &
			ap[kcnext], &c__1);
		i__1 = kcnext + k;
		i__2 = kcnext + k;
		i__3 = k - 1;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kcnext], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    }
	    kstep = 2;
	    kcnext = kcnext + k + 1;
	}

	kp = (i__1 = ipiv[k], abs(i__1));
	if (kp != k) {

/*           Interchange rows and columns K and KP in the leading */
/*           submatrix A(1:k+1,1:k+1) */

	    kpc = (kp - 1) * kp / 2 + 1;
	    i__1 = kp - 1;
	    zswap_(&i__1, &ap[kc], &c__1, &ap[kpc], &c__1);
	    kx = kpc + kp - 1;
	    i__1 = k - 1;
	    for (j = kp + 1; j <= i__1; ++j) {
		kx = kx + j - 1;
		i__2 = kc + j - 1;
		temp.r = ap[i__2].r, temp.i = ap[i__2].i;
		i__2 = kc + j - 1;
		i__3 = kx;
		ap[i__2].r = ap[i__3].r, ap[i__2].i = ap[i__3].i;
		i__2 = kx;
		ap[i__2].r = temp.r, ap[i__2].i = temp.i;
/* L40: */
	    }
	    i__1 = kc + k - 1;
	    temp.r = ap[i__1].r, temp.i = ap[i__1].i;
	    i__1 = kc + k - 1;
	    i__2 = kpc + kp - 1;
	    ap[i__1].r = ap[i__2].r, ap[i__1].i = ap[i__2].i;
	    i__1 = kpc + kp - 1;
	    ap[i__1].r = temp.r, ap[i__1].i = temp.i;
	    if (kstep == 2) {
		i__1 = kc + k + k - 1;
		temp.r = ap[i__1].r, temp.i = ap[i__1].i;
		i__1 = kc + k + k - 1;
		i__2 = kc + k + kp - 1;
		ap[i__1].r = ap[i__2].r, ap[i__1].i = ap[i__2].i;
		i__1 = kc + k + kp - 1;
		ap[i__1].r = temp.r, ap[i__1].i = temp.i;
	    }
	}

	k += kstep;
	kc = kcnext;
	goto L30;
L50:

	;
    } else {

/*        Compute inv(A) from the factorization A = L*D*L**T. */

/*        K is the main loop index, increasing from 1 to N in steps of */
/*        1 or 2, depending on the size of the diagonal blocks. */

	npp = *n * (*n + 1) / 2;
	k = *n;
	kc = npp;
L60:

/*        If K < 1, exit from loop. */

	if (k < 1) {
	    goto L80;
	}

	kcnext = kc - (*n - k + 2);
	if (ipiv[k] > 0) {

/*           1 x 1 diagonal block */

/*           Invert the diagonal block. */

	    i__1 = kc;
	    z_div(&z__1, &c_b1, &ap[kc]);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;

/*           Compute column K of the inverse. */

	    if (k < *n) {
		i__1 = *n - k;
		zcopy_(&i__1, &ap[kc + 1], &c__1, &work[1], &c__1);
		i__1 = *n - k;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[kc + *n - k + 1], &work[1], &
			c__1, &c_b2, &ap[kc + 1], &c__1);
		i__1 = kc;
		i__2 = kc;
		i__3 = *n - k;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kc + 1], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    }
	    kstep = 1;
	} else {

/*           2 x 2 diagonal block */

/*           Invert the diagonal block. */

	    i__1 = kcnext + 1;
	    t.r = ap[i__1].r, t.i = ap[i__1].i;
	    z_div(&z__1, &ap[kcnext], &t);
	    ak.r = z__1.r, ak.i = z__1.i;
	    z_div(&z__1, &ap[kc], &t);
	    akp1.r = z__1.r, akp1.i = z__1.i;
	    z_div(&z__1, &ap[kcnext + 1], &t);
	    akkp1.r = z__1.r, akkp1.i = z__1.i;
	    z__3.r = ak.r * akp1.r - ak.i * akp1.i, z__3.i = ak.r * akp1.i + 
		    ak.i * akp1.r;
	    z__2.r = z__3.r - 1., z__2.i = z__3.i + 0.;
	    z__1.r = t.r * z__2.r - t.i * z__2.i, z__1.i = t.r * z__2.i + t.i 
		    * z__2.r;
	    d__.r = z__1.r, d__.i = z__1.i;
	    i__1 = kcnext;
	    z_div(&z__1, &akp1, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    i__1 = kc;
	    z_div(&z__1, &ak, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    i__1 = kcnext + 1;
	    z__2.r = -akkp1.r, z__2.i = -akkp1.i;
	    z_div(&z__1, &z__2, &d__);
	    ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;

/*           Compute columns K-1 and K of the inverse. */

	    if (k < *n) {
		i__1 = *n - k;
		zcopy_(&i__1, &ap[kc + 1], &c__1, &work[1], &c__1);
		i__1 = *n - k;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[kc + (*n - k + 1)], &work[1], &
			c__1, &c_b2, &ap[kc + 1], &c__1);
		i__1 = kc;
		i__2 = kc;
		i__3 = *n - k;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kc + 1], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
		i__1 = kcnext + 1;
		i__2 = kcnext + 1;
		i__3 = *n - k;
		zdotu_(&z__2, &i__3, &ap[kc + 1], &c__1, &ap[kcnext + 2], &
			c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
		i__1 = *n - k;
		zcopy_(&i__1, &ap[kcnext + 2], &c__1, &work[1], &c__1);
		i__1 = *n - k;
		z__1.r = -1., z__1.i = 0.;
		zspmv_(uplo, &i__1, &z__1, &ap[kc + (*n - k + 1)], &work[1], &
			c__1, &c_b2, &ap[kcnext + 2], &c__1);
		i__1 = kcnext;
		i__2 = kcnext;
		i__3 = *n - k;
		zdotu_(&z__2, &i__3, &work[1], &c__1, &ap[kcnext + 2], &c__1);
		z__1.r = ap[i__2].r - z__2.r, z__1.i = ap[i__2].i - z__2.i;
		ap[i__1].r = z__1.r, ap[i__1].i = z__1.i;
	    }
	    kstep = 2;
	    kcnext -= *n - k + 3;
	}

	kp = (i__1 = ipiv[k], abs(i__1));
	if (kp != k) {

/*           Interchange rows and columns K and KP in the trailing */
/*           submatrix A(k-1:n,k-1:n) */

	    kpc = npp - (*n - kp + 1) * (*n - kp + 2) / 2 + 1;
	    if (kp < *n) {
		i__1 = *n - kp;
		zswap_(&i__1, &ap[kc + kp - k + 1], &c__1, &ap[kpc + 1], &
			c__1);
	    }
	    kx = kc + kp - k;
	    i__1 = kp - 1;
	    for (j = k + 1; j <= i__1; ++j) {
		kx = kx + *n - j + 1;
		i__2 = kc + j - k;
		temp.r = ap[i__2].r, temp.i = ap[i__2].i;
		i__2 = kc + j - k;
		i__3 = kx;
		ap[i__2].r = ap[i__3].r, ap[i__2].i = ap[i__3].i;
		i__2 = kx;
		ap[i__2].r = temp.r, ap[i__2].i = temp.i;
/* L70: */
	    }
	    i__1 = kc;
	    temp.r = ap[i__1].r, temp.i = ap[i__1].i;
	    i__1 = kc;
	    i__2 = kpc;
	    ap[i__1].r = ap[i__2].r, ap[i__1].i = ap[i__2].i;
	    i__1 = kpc;
	    ap[i__1].r = temp.r, ap[i__1].i = temp.i;
	    if (kstep == 2) {
		i__1 = kc - *n + k - 1;
		temp.r = ap[i__1].r, temp.i = ap[i__1].i;
		i__1 = kc - *n + k - 1;
		i__2 = kc - *n + kp - 1;
		ap[i__1].r = ap[i__2].r, ap[i__1].i = ap[i__2].i;
		i__1 = kc - *n + kp - 1;
		ap[i__1].r = temp.r, ap[i__1].i = temp.i;
	    }
	}

	k -= kstep;
	kc = kcnext;
	goto L60;
L80:
	;
    }

    return 0;

/*     End of ZSPTRI */

} /* zsptri_ */