|
- #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;
- #ifdef _MSC_VER
- static inline _Fcomplex Cf(complex *z) {_Fcomplex zz={z->r , z->i}; return zz;}
- static inline _Dcomplex Cd(doublecomplex *z) {_Dcomplex zz={z->r , z->i};return zz;}
- static inline _Fcomplex * _pCf(complex *z) {return (_Fcomplex*)z;}
- static inline _Dcomplex * _pCd(doublecomplex *z) {return (_Dcomplex*)z;}
- #else
- 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;}
- #endif
- #define pCf(z) (*_pCf(z))
- #define pCd(z) (*_pCd(z))
- typedef blasint logical;
-
- 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)); }
- #ifdef _MSC_VER
- #define c_div(c, a, b) {Cf(c)._Val[0] = (Cf(a)._Val[0]/Cf(b)._Val[0]); Cf(c)._Val[1]=(Cf(a)._Val[1]/Cf(b)._Val[1]);}
- #define z_div(c, a, b) {Cd(c)._Val[0] = (Cd(a)._Val[0]/Cd(b)._Val[0]); Cd(c)._Val[1]=(Cd(a)._Val[1]/df(b)._Val[1]);}
- #else
- #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
- #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
- #endif
- #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) = conjf(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) (cimagf(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++ */
-
-
- #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;
- }
- #ifdef _MSC_VER
- static _Fcomplex cpow_ui(complex x, integer n) {
- complex pow={1.0,0.0}; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x.r = 1/x.r, x.i=1/x.i;
- for(u = n; ; ) {
- if(u & 01) pow.r *= x.r, pow.i *= x.i;
- if(u >>= 1) x.r *= x.r, x.i *= x.i;
- else break;
- }
- }
- _Fcomplex p={pow.r, pow.i};
- return p;
- }
- #else
- 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;
- }
- #endif
- #ifdef _MSC_VER
- static _Dcomplex zpow_ui(_Dcomplex x, integer n) {
- _Dcomplex pow={1.0,0.0}; unsigned long int u;
- if(n != 0) {
- if(n < 0) n = -n, x._Val[0] = 1/x._Val[0], x._Val[1] =1/x._Val[1];
- for(u = n; ; ) {
- if(u & 01) pow._Val[0] *= x._Val[0], pow._Val[1] *= x._Val[1];
- if(u >>= 1) x._Val[0] *= x._Val[0], x._Val[1] *= x._Val[1];
- else break;
- }
- }
- _Dcomplex p = {pow._Val[0], pow._Val[1]};
- return p;
- }
- #else
- 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;
- }
- #endif
- 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;
- #ifdef _MSC_VER
- _Fcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conjf(Cf(&x[i]))._Val[0] * Cf(&y[i])._Val[0];
- zdotc._Val[1] += conjf(Cf(&x[i]))._Val[1] * Cf(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conjf(Cf(&x[i*incx]))._Val[0] * Cf(&y[i*incy])._Val[0];
- zdotc._Val[1] += conjf(Cf(&x[i*incx]))._Val[1] * Cf(&y[i*incy])._Val[1];
- }
- }
- pCf(z) = zdotc;
- }
- #else
- _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;
- }
- #endif
- static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Dcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conj(Cd(&x[i]))._Val[0] * Cd(&y[i])._Val[0];
- zdotc._Val[1] += conj(Cd(&x[i]))._Val[1] * Cd(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += conj(Cd(&x[i*incx]))._Val[0] * Cd(&y[i*incy])._Val[0];
- zdotc._Val[1] += conj(Cd(&x[i*incx]))._Val[1] * Cd(&y[i*incy])._Val[1];
- }
- }
- pCd(z) = zdotc;
- }
- #else
- _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;
- }
- #endif
- static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Fcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cf(&x[i])._Val[0] * Cf(&y[i])._Val[0];
- zdotc._Val[1] += Cf(&x[i])._Val[1] * Cf(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cf(&x[i*incx])._Val[0] * Cf(&y[i*incy])._Val[0];
- zdotc._Val[1] += Cf(&x[i*incx])._Val[1] * Cf(&y[i*incy])._Val[1];
- }
- }
- pCf(z) = zdotc;
- }
- #else
- _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;
- }
- #endif
- static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
- integer n = *n_, incx = *incx_, incy = *incy_, i;
- #ifdef _MSC_VER
- _Dcomplex zdotc = {0.0, 0.0};
- if (incx == 1 && incy == 1) {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cd(&x[i])._Val[0] * Cd(&y[i])._Val[0];
- zdotc._Val[1] += Cd(&x[i])._Val[1] * Cd(&y[i])._Val[1];
- }
- } else {
- for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
- zdotc._Val[0] += Cd(&x[i*incx])._Val[0] * Cd(&y[i*incy])._Val[0];
- zdotc._Val[1] += Cd(&x[i*incx])._Val[1] * Cd(&y[i*incy])._Val[1];
- }
- }
- pCd(z) = zdotc;
- }
- #else
- _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 integer c__1 = 1;
- static doublereal c_b36 = .5;
-
- /* > \brief \b DLATPS solves a triangular system of equations with the matrix held in packed storage. */
-
- /* =========== DOCUMENTATION =========== */
-
- /* Online html documentation available at */
- /* http://www.netlib.org/lapack/explore-html/ */
-
- /* > \htmlonly */
- /* > Download DLATPS + dependencies */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlatps.
- f"> */
- /* > [TGZ]</a> */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlatps.
- f"> */
- /* > [ZIP]</a> */
- /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlatps.
- f"> */
- /* > [TXT]</a> */
- /* > \endhtmlonly */
-
- /* Definition: */
- /* =========== */
-
- /* SUBROUTINE DLATPS( UPLO, TRANS, DIAG, NORMIN, N, AP, X, SCALE, */
- /* CNORM, INFO ) */
-
- /* CHARACTER DIAG, NORMIN, TRANS, UPLO */
- /* INTEGER INFO, N */
- /* DOUBLE PRECISION SCALE */
- /* DOUBLE PRECISION AP( * ), CNORM( * ), X( * ) */
-
-
- /* > \par Purpose: */
- /* ============= */
- /* > */
- /* > \verbatim */
- /* > */
- /* > DLATPS solves one of the triangular systems */
- /* > */
- /* > A *x = s*b or A**T*x = s*b */
- /* > */
- /* > with scaling to prevent overflow, where A is an upper or lower */
- /* > triangular matrix stored in packed form. Here A**T denotes the */
- /* > transpose of A, x and b are n-element vectors, and s is a scaling */
- /* > factor, usually less than or equal to 1, chosen so that the */
- /* > components of x will be less than the overflow threshold. If the */
- /* > unscaled problem will not cause overflow, the Level 2 BLAS routine */
- /* > DTPSV is called. If the matrix A is singular (A(j,j) = 0 for some j), */
- /* > then s is set to 0 and a non-trivial solution to A*x = 0 is returned. */
- /* > \endverbatim */
-
- /* Arguments: */
- /* ========== */
-
- /* > \param[in] UPLO */
- /* > \verbatim */
- /* > UPLO is CHARACTER*1 */
- /* > Specifies whether the matrix A is upper or lower triangular. */
- /* > = 'U': Upper triangular */
- /* > = 'L': Lower triangular */
- /* > \endverbatim */
- /* > */
- /* > \param[in] TRANS */
- /* > \verbatim */
- /* > TRANS is CHARACTER*1 */
- /* > Specifies the operation applied to A. */
- /* > = 'N': Solve A * x = s*b (No transpose) */
- /* > = 'T': Solve A**T* x = s*b (Transpose) */
- /* > = 'C': Solve A**T* x = s*b (Conjugate transpose = Transpose) */
- /* > \endverbatim */
- /* > */
- /* > \param[in] DIAG */
- /* > \verbatim */
- /* > DIAG is CHARACTER*1 */
- /* > Specifies whether or not the matrix A is unit triangular. */
- /* > = 'N': Non-unit triangular */
- /* > = 'U': Unit triangular */
- /* > \endverbatim */
- /* > */
- /* > \param[in] NORMIN */
- /* > \verbatim */
- /* > NORMIN is CHARACTER*1 */
- /* > Specifies whether CNORM has been set or not. */
- /* > = 'Y': CNORM contains the column norms on entry */
- /* > = 'N': CNORM is not set on entry. On exit, the norms will */
- /* > be computed and stored in CNORM. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] N */
- /* > \verbatim */
- /* > N is INTEGER */
- /* > The order of the matrix A. N >= 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] AP */
- /* > \verbatim */
- /* > AP is DOUBLE PRECISION array, dimension (N*(N+1)/2) */
- /* > The upper or lower triangular matrix A, packed columnwise in */
- /* > a linear array. The j-th column of A is stored in the array */
- /* > AP as follows: */
- /* > if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; */
- /* > if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] X */
- /* > \verbatim */
- /* > X is DOUBLE PRECISION array, dimension (N) */
- /* > On entry, the right hand side b of the triangular system. */
- /* > On exit, X is overwritten by the solution vector x. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] SCALE */
- /* > \verbatim */
- /* > SCALE is DOUBLE PRECISION */
- /* > The scaling factor s for the triangular system */
- /* > A * x = s*b or A**T* x = s*b. */
- /* > If SCALE = 0, the matrix A is singular or badly scaled, and */
- /* > the vector x is an exact or approximate solution to A*x = 0. */
- /* > \endverbatim */
- /* > */
- /* > \param[in,out] CNORM */
- /* > \verbatim */
- /* > CNORM is DOUBLE PRECISION array, dimension (N) */
- /* > */
- /* > If NORMIN = 'Y', CNORM is an input argument and CNORM(j) */
- /* > contains the norm of the off-diagonal part of the j-th column */
- /* > of A. If TRANS = 'N', CNORM(j) must be greater than or equal */
- /* > to the infinity-norm, and if TRANS = 'T' or 'C', CNORM(j) */
- /* > must be greater than or equal to the 1-norm. */
- /* > */
- /* > If NORMIN = 'N', CNORM is an output argument and CNORM(j) */
- /* > returns the 1-norm of the offdiagonal part of the j-th column */
- /* > of A. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] INFO */
- /* > \verbatim */
- /* > INFO is INTEGER */
- /* > = 0: successful exit */
- /* > < 0: if INFO = -k, the k-th argument had an illegal value */
- /* > \endverbatim */
-
- /* Authors: */
- /* ======== */
-
- /* > \author Univ. of Tennessee */
- /* > \author Univ. of California Berkeley */
- /* > \author Univ. of Colorado Denver */
- /* > \author NAG Ltd. */
-
- /* > \date December 2016 */
-
- /* > \ingroup doubleOTHERauxiliary */
-
- /* > \par Further Details: */
- /* ===================== */
- /* > */
- /* > \verbatim */
- /* > */
- /* > A rough bound on x is computed; if that is less than overflow, DTPSV */
- /* > is called, otherwise, specific code is used which checks for possible */
- /* > overflow or divide-by-zero at every operation. */
- /* > */
- /* > A columnwise scheme is used for solving A*x = b. The basic algorithm */
- /* > if A is lower triangular is */
- /* > */
- /* > x[1:n] := b[1:n] */
- /* > for j = 1, ..., n */
- /* > x(j) := x(j) / A(j,j) */
- /* > x[j+1:n] := x[j+1:n] - x(j) * A[j+1:n,j] */
- /* > end */
- /* > */
- /* > Define bounds on the components of x after j iterations of the loop: */
- /* > M(j) = bound on x[1:j] */
- /* > G(j) = bound on x[j+1:n] */
- /* > Initially, let M(0) = 0 and G(0) = f2cmax{x(i), i=1,...,n}. */
- /* > */
- /* > Then for iteration j+1 we have */
- /* > M(j+1) <= G(j) / | A(j+1,j+1) | */
- /* > G(j+1) <= G(j) + M(j+1) * | A[j+2:n,j+1] | */
- /* > <= G(j) ( 1 + CNORM(j+1) / | A(j+1,j+1) | ) */
- /* > */
- /* > where CNORM(j+1) is greater than or equal to the infinity-norm of */
- /* > column j+1 of A, not counting the diagonal. Hence */
- /* > */
- /* > G(j) <= G(0) product ( 1 + CNORM(i) / | A(i,i) | ) */
- /* > 1<=i<=j */
- /* > and */
- /* > */
- /* > |x(j)| <= ( G(0) / |A(j,j)| ) product ( 1 + CNORM(i) / |A(i,i)| ) */
- /* > 1<=i< j */
- /* > */
- /* > Since |x(j)| <= M(j), we use the Level 2 BLAS routine DTPSV if the */
- /* > reciprocal of the largest M(j), j=1,..,n, is larger than */
- /* > f2cmax(underflow, 1/overflow). */
- /* > */
- /* > The bound on x(j) is also used to determine when a step in the */
- /* > columnwise method can be performed without fear of overflow. If */
- /* > the computed bound is greater than a large constant, x is scaled to */
- /* > prevent overflow, but if the bound overflows, x is set to 0, x(j) to */
- /* > 1, and scale to 0, and a non-trivial solution to A*x = 0 is found. */
- /* > */
- /* > Similarly, a row-wise scheme is used to solve A**T*x = b. The basic */
- /* > algorithm for A upper triangular is */
- /* > */
- /* > for j = 1, ..., n */
- /* > x(j) := ( b(j) - A[1:j-1,j]**T * x[1:j-1] ) / A(j,j) */
- /* > end */
- /* > */
- /* > We simultaneously compute two bounds */
- /* > G(j) = bound on ( b(i) - A[1:i-1,i]**T * x[1:i-1] ), 1<=i<=j */
- /* > M(j) = bound on x(i), 1<=i<=j */
- /* > */
- /* > The initial values are G(0) = 0, M(0) = f2cmax{b(i), i=1,..,n}, and we */
- /* > add the constraint G(j) >= G(j-1) and M(j) >= M(j-1) for j >= 1. */
- /* > Then the bound on x(j) is */
- /* > */
- /* > M(j) <= M(j-1) * ( 1 + CNORM(j) ) / | A(j,j) | */
- /* > */
- /* > <= M(0) * product ( ( 1 + CNORM(i) ) / |A(i,i)| ) */
- /* > 1<=i<=j */
- /* > */
- /* > and we can safely call DTPSV if 1/M(n) and 1/G(n) are both greater */
- /* > than f2cmax(underflow, 1/overflow). */
- /* > \endverbatim */
- /* > */
- /* ===================================================================== */
- /* Subroutine */ void dlatps_(char *uplo, char *trans, char *diag, char *
- normin, integer *n, doublereal *ap, doublereal *x, doublereal *scale,
- doublereal *cnorm, integer *info)
- {
- /* System generated locals */
- integer i__1, i__2, i__3;
- doublereal d__1, d__2, d__3;
-
- /* Local variables */
- integer jinc, jlen;
- extern doublereal ddot_(integer *, doublereal *, integer *, doublereal *,
- integer *);
- doublereal xbnd;
- integer imax;
- doublereal tmax, tjjs, xmax, grow, sumj;
- integer i__, j;
- extern /* Subroutine */ void dscal_(integer *, doublereal *, doublereal *,
- integer *);
- extern logical lsame_(char *, char *);
- doublereal tscal, uscal;
- extern doublereal dasum_(integer *, doublereal *, integer *);
- integer jlast;
- extern /* Subroutine */ void daxpy_(integer *, doublereal *, doublereal *,
- integer *, doublereal *, integer *);
- logical upper;
- extern /* Subroutine */ void dtpsv_(char *, char *, char *, integer *,
- doublereal *, doublereal *, integer *);
- extern doublereal dlamch_(char *);
- integer ip;
- doublereal xj;
- extern integer idamax_(integer *, doublereal *, integer *);
- extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
- doublereal bignum;
- logical notran;
- integer jfirst;
- doublereal smlnum;
- logical nounit;
- doublereal rec, tjj;
-
-
- /* -- LAPACK auxiliary 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 */
-
-
- /* ===================================================================== */
-
-
- /* Parameter adjustments */
- --cnorm;
- --x;
- --ap;
-
- /* Function Body */
- *info = 0;
- upper = lsame_(uplo, "U");
- notran = lsame_(trans, "N");
- nounit = lsame_(diag, "N");
-
- /* Test the input parameters. */
-
- if (! upper && ! lsame_(uplo, "L")) {
- *info = -1;
- } else if (! notran && ! lsame_(trans, "T") && !
- lsame_(trans, "C")) {
- *info = -2;
- } else if (! nounit && ! lsame_(diag, "U")) {
- *info = -3;
- } else if (! lsame_(normin, "Y") && ! lsame_(normin,
- "N")) {
- *info = -4;
- } else if (*n < 0) {
- *info = -5;
- }
- if (*info != 0) {
- i__1 = -(*info);
- xerbla_("DLATPS", &i__1, (ftnlen)6);
- return;
- }
-
- /* Quick return if possible */
-
- if (*n == 0) {
- return;
- }
-
- /* Determine machine dependent parameters to control overflow. */
-
- smlnum = dlamch_("Safe minimum") / dlamch_("Precision");
- bignum = 1. / smlnum;
- *scale = 1.;
-
- if (lsame_(normin, "N")) {
-
- /* Compute the 1-norm of each column, not including the diagonal. */
-
- if (upper) {
-
- /* A is upper triangular. */
-
- ip = 1;
- i__1 = *n;
- for (j = 1; j <= i__1; ++j) {
- i__2 = j - 1;
- cnorm[j] = dasum_(&i__2, &ap[ip], &c__1);
- ip += j;
- /* L10: */
- }
- } else {
-
- /* A is lower triangular. */
-
- ip = 1;
- i__1 = *n - 1;
- for (j = 1; j <= i__1; ++j) {
- i__2 = *n - j;
- cnorm[j] = dasum_(&i__2, &ap[ip + 1], &c__1);
- ip = ip + *n - j + 1;
- /* L20: */
- }
- cnorm[*n] = 0.;
- }
- }
-
- /* Scale the column norms by TSCAL if the maximum element in CNORM is */
- /* greater than BIGNUM. */
-
- imax = idamax_(n, &cnorm[1], &c__1);
- tmax = cnorm[imax];
- if (tmax <= bignum) {
- tscal = 1.;
- } else {
- tscal = 1. / (smlnum * tmax);
- dscal_(n, &tscal, &cnorm[1], &c__1);
- }
-
- /* Compute a bound on the computed solution vector to see if the */
- /* Level 2 BLAS routine DTPSV can be used. */
-
- j = idamax_(n, &x[1], &c__1);
- xmax = (d__1 = x[j], abs(d__1));
- xbnd = xmax;
- if (notran) {
-
- /* Compute the growth in A * x = b. */
-
- if (upper) {
- jfirst = *n;
- jlast = 1;
- jinc = -1;
- } else {
- jfirst = 1;
- jlast = *n;
- jinc = 1;
- }
-
- if (tscal != 1.) {
- grow = 0.;
- goto L50;
- }
-
- if (nounit) {
-
- /* A is non-unit triangular. */
-
- /* Compute GROW = 1/G(j) and XBND = 1/M(j). */
- /* Initially, G(0) = f2cmax{x(i), i=1,...,n}. */
-
- grow = 1. / f2cmax(xbnd,smlnum);
- xbnd = grow;
- ip = jfirst * (jfirst + 1) / 2;
- jlen = *n;
- i__1 = jlast;
- i__2 = jinc;
- for (j = jfirst; i__2 < 0 ? j >= i__1 : j <= i__1; j += i__2) {
-
- /* Exit the loop if the growth factor is too small. */
-
- if (grow <= smlnum) {
- goto L50;
- }
-
- /* M(j) = G(j-1) / abs(A(j,j)) */
-
- tjj = (d__1 = ap[ip], abs(d__1));
- /* Computing MIN */
- d__1 = xbnd, d__2 = f2cmin(1.,tjj) * grow;
- xbnd = f2cmin(d__1,d__2);
- if (tjj + cnorm[j] >= smlnum) {
-
- /* G(j) = G(j-1)*( 1 + CNORM(j) / abs(A(j,j)) ) */
-
- grow *= tjj / (tjj + cnorm[j]);
- } else {
-
- /* G(j) could overflow, set GROW to 0. */
-
- grow = 0.;
- }
- ip += jinc * jlen;
- --jlen;
- /* L30: */
- }
- grow = xbnd;
- } else {
-
- /* A is unit triangular. */
-
- /* Compute GROW = 1/G(j), where G(0) = f2cmax{x(i), i=1,...,n}. */
-
- /* Computing MIN */
- d__1 = 1., d__2 = 1. / f2cmax(xbnd,smlnum);
- grow = f2cmin(d__1,d__2);
- i__2 = jlast;
- i__1 = jinc;
- for (j = jfirst; i__1 < 0 ? j >= i__2 : j <= i__2; j += i__1) {
-
- /* Exit the loop if the growth factor is too small. */
-
- if (grow <= smlnum) {
- goto L50;
- }
-
- /* G(j) = G(j-1)*( 1 + CNORM(j) ) */
-
- grow *= 1. / (cnorm[j] + 1.);
- /* L40: */
- }
- }
- L50:
-
- ;
- } else {
-
- /* Compute the growth in A**T * x = b. */
-
- if (upper) {
- jfirst = 1;
- jlast = *n;
- jinc = 1;
- } else {
- jfirst = *n;
- jlast = 1;
- jinc = -1;
- }
-
- if (tscal != 1.) {
- grow = 0.;
- goto L80;
- }
-
- if (nounit) {
-
- /* A is non-unit triangular. */
-
- /* Compute GROW = 1/G(j) and XBND = 1/M(j). */
- /* Initially, M(0) = f2cmax{x(i), i=1,...,n}. */
-
- grow = 1. / f2cmax(xbnd,smlnum);
- xbnd = grow;
- ip = jfirst * (jfirst + 1) / 2;
- jlen = 1;
- i__1 = jlast;
- i__2 = jinc;
- for (j = jfirst; i__2 < 0 ? j >= i__1 : j <= i__1; j += i__2) {
-
- /* Exit the loop if the growth factor is too small. */
-
- if (grow <= smlnum) {
- goto L80;
- }
-
- /* G(j) = f2cmax( G(j-1), M(j-1)*( 1 + CNORM(j) ) ) */
-
- xj = cnorm[j] + 1.;
- /* Computing MIN */
- d__1 = grow, d__2 = xbnd / xj;
- grow = f2cmin(d__1,d__2);
-
- /* M(j) = M(j-1)*( 1 + CNORM(j) ) / abs(A(j,j)) */
-
- tjj = (d__1 = ap[ip], abs(d__1));
- if (xj > tjj) {
- xbnd *= tjj / xj;
- }
- ++jlen;
- ip += jinc * jlen;
- /* L60: */
- }
- grow = f2cmin(grow,xbnd);
- } else {
-
- /* A is unit triangular. */
-
- /* Compute GROW = 1/G(j), where G(0) = f2cmax{x(i), i=1,...,n}. */
-
- /* Computing MIN */
- d__1 = 1., d__2 = 1. / f2cmax(xbnd,smlnum);
- grow = f2cmin(d__1,d__2);
- i__2 = jlast;
- i__1 = jinc;
- for (j = jfirst; i__1 < 0 ? j >= i__2 : j <= i__2; j += i__1) {
-
- /* Exit the loop if the growth factor is too small. */
-
- if (grow <= smlnum) {
- goto L80;
- }
-
- /* G(j) = ( 1 + CNORM(j) )*G(j-1) */
-
- xj = cnorm[j] + 1.;
- grow /= xj;
- /* L70: */
- }
- }
- L80:
- ;
- }
-
- if (grow * tscal > smlnum) {
-
- /* Use the Level 2 BLAS solve if the reciprocal of the bound on */
- /* elements of X is not too small. */
-
- dtpsv_(uplo, trans, diag, n, &ap[1], &x[1], &c__1);
- } else {
-
- /* Use a Level 1 BLAS solve, scaling intermediate results. */
-
- if (xmax > bignum) {
-
- /* Scale X so that its components are less than or equal to */
- /* BIGNUM in absolute value. */
-
- *scale = bignum / xmax;
- dscal_(n, scale, &x[1], &c__1);
- xmax = bignum;
- }
-
- if (notran) {
-
- /* Solve A * x = b */
-
- ip = jfirst * (jfirst + 1) / 2;
- i__1 = jlast;
- i__2 = jinc;
- for (j = jfirst; i__2 < 0 ? j >= i__1 : j <= i__1; j += i__2) {
-
- /* Compute x(j) = b(j) / A(j,j), scaling x if necessary. */
-
- xj = (d__1 = x[j], abs(d__1));
- if (nounit) {
- tjjs = ap[ip] * tscal;
- } else {
- tjjs = tscal;
- if (tscal == 1.) {
- goto L100;
- }
- }
- tjj = abs(tjjs);
- if (tjj > smlnum) {
-
- /* abs(A(j,j)) > SMLNUM: */
-
- if (tjj < 1.) {
- if (xj > tjj * bignum) {
-
- /* Scale x by 1/b(j). */
-
- rec = 1. / xj;
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- xmax *= rec;
- }
- }
- x[j] /= tjjs;
- xj = (d__1 = x[j], abs(d__1));
- } else if (tjj > 0.) {
-
- /* 0 < abs(A(j,j)) <= SMLNUM: */
-
- if (xj > tjj * bignum) {
-
- /* Scale x by (1/abs(x(j)))*abs(A(j,j))*BIGNUM */
- /* to avoid overflow when dividing by A(j,j). */
-
- rec = tjj * bignum / xj;
- if (cnorm[j] > 1.) {
-
- /* Scale by 1/CNORM(j) to avoid overflow when */
- /* multiplying x(j) times column j. */
-
- rec /= cnorm[j];
- }
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- xmax *= rec;
- }
- x[j] /= tjjs;
- xj = (d__1 = x[j], abs(d__1));
- } else {
-
- /* A(j,j) = 0: Set x(1:n) = 0, x(j) = 1, and */
- /* scale = 0, and compute a solution to A*x = 0. */
-
- i__3 = *n;
- for (i__ = 1; i__ <= i__3; ++i__) {
- x[i__] = 0.;
- /* L90: */
- }
- x[j] = 1.;
- xj = 1.;
- *scale = 0.;
- xmax = 0.;
- }
- L100:
-
- /* Scale x if necessary to avoid overflow when adding a */
- /* multiple of column j of A. */
-
- if (xj > 1.) {
- rec = 1. / xj;
- if (cnorm[j] > (bignum - xmax) * rec) {
-
- /* Scale x by 1/(2*abs(x(j))). */
-
- rec *= .5;
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- }
- } else if (xj * cnorm[j] > bignum - xmax) {
-
- /* Scale x by 1/2. */
-
- dscal_(n, &c_b36, &x[1], &c__1);
- *scale *= .5;
- }
-
- if (upper) {
- if (j > 1) {
-
- /* Compute the update */
- /* x(1:j-1) := x(1:j-1) - x(j) * A(1:j-1,j) */
-
- i__3 = j - 1;
- d__1 = -x[j] * tscal;
- daxpy_(&i__3, &d__1, &ap[ip - j + 1], &c__1, &x[1], &
- c__1);
- i__3 = j - 1;
- i__ = idamax_(&i__3, &x[1], &c__1);
- xmax = (d__1 = x[i__], abs(d__1));
- }
- ip -= j;
- } else {
- if (j < *n) {
-
- /* Compute the update */
- /* x(j+1:n) := x(j+1:n) - x(j) * A(j+1:n,j) */
-
- i__3 = *n - j;
- d__1 = -x[j] * tscal;
- daxpy_(&i__3, &d__1, &ap[ip + 1], &c__1, &x[j + 1], &
- c__1);
- i__3 = *n - j;
- i__ = j + idamax_(&i__3, &x[j + 1], &c__1);
- xmax = (d__1 = x[i__], abs(d__1));
- }
- ip = ip + *n - j + 1;
- }
- /* L110: */
- }
-
- } else {
-
- /* Solve A**T * x = b */
-
- ip = jfirst * (jfirst + 1) / 2;
- jlen = 1;
- i__2 = jlast;
- i__1 = jinc;
- for (j = jfirst; i__1 < 0 ? j >= i__2 : j <= i__2; j += i__1) {
-
- /* Compute x(j) = b(j) - sum A(k,j)*x(k). */
- /* k<>j */
-
- xj = (d__1 = x[j], abs(d__1));
- uscal = tscal;
- rec = 1. / f2cmax(xmax,1.);
- if (cnorm[j] > (bignum - xj) * rec) {
-
- /* If x(j) could overflow, scale x by 1/(2*XMAX). */
-
- rec *= .5;
- if (nounit) {
- tjjs = ap[ip] * tscal;
- } else {
- tjjs = tscal;
- }
- tjj = abs(tjjs);
- if (tjj > 1.) {
-
- /* Divide by A(j,j) when scaling x if A(j,j) > 1. */
-
- /* Computing MIN */
- d__1 = 1., d__2 = rec * tjj;
- rec = f2cmin(d__1,d__2);
- uscal /= tjjs;
- }
- if (rec < 1.) {
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- xmax *= rec;
- }
- }
-
- sumj = 0.;
- if (uscal == 1.) {
-
- /* If the scaling needed for A in the dot product is 1, */
- /* call DDOT to perform the dot product. */
-
- if (upper) {
- i__3 = j - 1;
- sumj = ddot_(&i__3, &ap[ip - j + 1], &c__1, &x[1], &
- c__1);
- } else if (j < *n) {
- i__3 = *n - j;
- sumj = ddot_(&i__3, &ap[ip + 1], &c__1, &x[j + 1], &
- c__1);
- }
- } else {
-
- /* Otherwise, use in-line code for the dot product. */
-
- if (upper) {
- i__3 = j - 1;
- for (i__ = 1; i__ <= i__3; ++i__) {
- sumj += ap[ip - j + i__] * uscal * x[i__];
- /* L120: */
- }
- } else if (j < *n) {
- i__3 = *n - j;
- for (i__ = 1; i__ <= i__3; ++i__) {
- sumj += ap[ip + i__] * uscal * x[j + i__];
- /* L130: */
- }
- }
- }
-
- if (uscal == tscal) {
-
- /* Compute x(j) := ( x(j) - sumj ) / A(j,j) if 1/A(j,j) */
- /* was not used to scale the dotproduct. */
-
- x[j] -= sumj;
- xj = (d__1 = x[j], abs(d__1));
- if (nounit) {
-
- /* Compute x(j) = x(j) / A(j,j), scaling if necessary. */
-
- tjjs = ap[ip] * tscal;
- } else {
- tjjs = tscal;
- if (tscal == 1.) {
- goto L150;
- }
- }
- tjj = abs(tjjs);
- if (tjj > smlnum) {
-
- /* abs(A(j,j)) > SMLNUM: */
-
- if (tjj < 1.) {
- if (xj > tjj * bignum) {
-
- /* Scale X by 1/abs(x(j)). */
-
- rec = 1. / xj;
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- xmax *= rec;
- }
- }
- x[j] /= tjjs;
- } else if (tjj > 0.) {
-
- /* 0 < abs(A(j,j)) <= SMLNUM: */
-
- if (xj > tjj * bignum) {
-
- /* Scale x by (1/abs(x(j)))*abs(A(j,j))*BIGNUM. */
-
- rec = tjj * bignum / xj;
- dscal_(n, &rec, &x[1], &c__1);
- *scale *= rec;
- xmax *= rec;
- }
- x[j] /= tjjs;
- } else {
-
- /* A(j,j) = 0: Set x(1:n) = 0, x(j) = 1, and */
- /* scale = 0, and compute a solution to A**T*x = 0. */
-
- i__3 = *n;
- for (i__ = 1; i__ <= i__3; ++i__) {
- x[i__] = 0.;
- /* L140: */
- }
- x[j] = 1.;
- *scale = 0.;
- xmax = 0.;
- }
- L150:
- ;
- } else {
-
- /* Compute x(j) := x(j) / A(j,j) - sumj if the dot */
- /* product has already been divided by 1/A(j,j). */
-
- x[j] = x[j] / tjjs - sumj;
- }
- /* Computing MAX */
- d__2 = xmax, d__3 = (d__1 = x[j], abs(d__1));
- xmax = f2cmax(d__2,d__3);
- ++jlen;
- ip += jinc * jlen;
- /* L160: */
- }
- }
- *scale /= tscal;
- }
-
- /* Scale the column norms by 1/TSCAL for return. */
-
- if (tscal != 1.) {
- d__1 = 1. / tscal;
- dscal_(n, &d__1, &cnorm[1], &c__1);
- }
-
- return;
-
- /* End of DLATPS */
-
- } /* dlatps_ */
|