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- #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 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)); }
- #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++ */
-
- #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;
- }
- #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 real c_b32 = 0.f;
-
- /* > \brief \b SLAMCHF77 deprecated */
-
- /* =========== DOCUMENTATION =========== */
-
- /* Online html documentation available at */
- /* http://www.netlib.org/lapack/explore-html/ */
-
- /* Definition: */
- /* =========== */
-
- /* REAL FUNCTION SLAMCH( CMACH ) */
-
- /* CHARACTER CMACH */
-
-
- /* > \par Purpose: */
- /* ============= */
- /* > */
- /* > \verbatim */
- /* > */
- /* > SLAMCH determines single precision machine parameters. */
- /* > \endverbatim */
-
- /* Arguments: */
- /* ========== */
-
- /* > \param[in] CMACH */
- /* > \verbatim */
- /* > Specifies the value to be returned by SLAMCH: */
- /* > = 'E' or 'e', SLAMCH := eps */
- /* > = 'S' or 's , SLAMCH := sfmin */
- /* > = 'B' or 'b', SLAMCH := base */
- /* > = 'P' or 'p', SLAMCH := eps*base */
- /* > = 'N' or 'n', SLAMCH := t */
- /* > = 'R' or 'r', SLAMCH := rnd */
- /* > = 'M' or 'm', SLAMCH := emin */
- /* > = 'U' or 'u', SLAMCH := rmin */
- /* > = 'L' or 'l', SLAMCH := emax */
- /* > = 'O' or 'o', SLAMCH := rmax */
- /* > where */
- /* > eps = relative machine precision */
- /* > sfmin = safe minimum, such that 1/sfmin does not overflow */
- /* > base = base of the machine */
- /* > prec = eps*base */
- /* > t = number of (base) digits in the mantissa */
- /* > rnd = 1.0 when rounding occurs in addition, 0.0 otherwise */
- /* > emin = minimum exponent before (gradual) underflow */
- /* > rmin = underflow threshold - base**(emin-1) */
- /* > emax = largest exponent before overflow */
- /* > rmax = overflow threshold - (base**emax)*(1-eps) */
- /* > \endverbatim */
-
- /* Authors: */
- /* ======== */
-
- /* > \author Univ. of Tennessee */
- /* > \author Univ. of California Berkeley */
- /* > \author Univ. of Colorado Denver */
- /* > \author NAG Ltd. */
-
- /* > \date April 2012 */
-
- /* > \ingroup auxOTHERauxiliary */
-
- /* ===================================================================== */
- real slamch_(char *cmach)
- {
- /* Initialized data */
-
- static logical first = TRUE_;
-
- /* System generated locals */
- integer i__1;
- real ret_val;
-
- /* Local variables */
- static real base;
- integer beta;
- static real emin, prec, emax;
- integer imin, imax;
- logical lrnd;
- static real rmin, rmax, t;
- real rmach;
- extern logical lsame_(char *, char *);
- real small;
- static real sfmin;
- extern /* Subroutine */ int slamc2_(integer *, integer *, logical *, real
- *, integer *, real *, integer *, real *);
- integer it;
- static real rnd, eps;
-
-
- /* -- 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..-- */
- /* April 2012 */
-
-
- if (first) {
- slamc2_(&beta, &it, &lrnd, &eps, &imin, &rmin, &imax, &rmax);
- base = (real) beta;
- t = (real) it;
- if (lrnd) {
- rnd = 1.f;
- i__1 = 1 - it;
- eps = pow_ri(&base, &i__1) / 2;
- } else {
- rnd = 0.f;
- i__1 = 1 - it;
- eps = pow_ri(&base, &i__1);
- }
- prec = eps * base;
- emin = (real) imin;
- emax = (real) imax;
- sfmin = rmin;
- small = 1.f / rmax;
- if (small >= sfmin) {
-
- /* Use SMALL plus a bit, to avoid the possibility of rounding */
- /* causing overflow when computing 1/sfmin. */
-
- sfmin = small * (eps + 1.f);
- }
- }
-
- if (lsame_(cmach, "E")) {
- rmach = eps;
- } else if (lsame_(cmach, "S")) {
- rmach = sfmin;
- } else if (lsame_(cmach, "B")) {
- rmach = base;
- } else if (lsame_(cmach, "P")) {
- rmach = prec;
- } else if (lsame_(cmach, "N")) {
- rmach = t;
- } else if (lsame_(cmach, "R")) {
- rmach = rnd;
- } else if (lsame_(cmach, "M")) {
- rmach = emin;
- } else if (lsame_(cmach, "U")) {
- rmach = rmin;
- } else if (lsame_(cmach, "L")) {
- rmach = emax;
- } else if (lsame_(cmach, "O")) {
- rmach = rmax;
- }
-
- ret_val = rmach;
- first = FALSE_;
- return ret_val;
-
- /* End of SLAMCH */
-
- } /* slamch_ */
-
-
- /* *********************************************************************** */
-
- /* > \brief \b SLAMC1 */
- /* > \details */
- /* > \b Purpose: */
- /* > \verbatim */
- /* > SLAMC1 determines the machine parameters given by BETA, T, RND, and */
- /* > IEEE1. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] BETA */
- /* > \verbatim */
- /* > The base of the machine. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] T */
- /* > \verbatim */
- /* > The number of ( BETA ) digits in the mantissa. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RND */
- /* > \verbatim */
- /* > Specifies whether proper rounding ( RND = .TRUE. ) or */
- /* > chopping ( RND = .FALSE. ) occurs in addition. This may not */
- /* > be a reliable guide to the way in which the machine performs */
- /* > its arithmetic. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] IEEE1 */
- /* > \verbatim */
- /* > Specifies whether rounding appears to be done in the IEEE */
- /* > 'round to nearest' style. */
- /* > \endverbatim */
- /* > \author LAPACK is a software package provided by Univ. of Tennessee, Univ. of California Berkeley, Univ.
- of Colorado Denver and NAG Ltd.. */
- /* > \date April 2012 */
- /* > \ingroup auxOTHERauxiliary */
- /* > */
- /* > \details \b Further \b Details */
- /* > \verbatim */
- /* > */
- /* > The routine is based on the routine ENVRON by Malcolm and */
- /* > incorporates suggestions by Gentleman and Marovich. See */
- /* > */
- /* > Malcolm M. A. (1972) Algorithms to reveal properties of */
- /* > floating-point arithmetic. Comms. of the ACM, 15, 949-951. */
- /* > */
- /* > Gentleman W. M. and Marovich S. B. (1974) More on algorithms */
- /* > that reveal properties of floating point arithmetic units. */
- /* > Comms. of the ACM, 17, 276-277. */
- /* > \endverbatim */
- /* > */
- /* Subroutine */ int slamc1_(integer *beta, integer *t, logical *rnd, logical
- *ieee1)
- {
- /* Initialized data */
-
- static logical first = TRUE_;
-
- /* System generated locals */
- real r__1, r__2;
-
- /* Local variables */
- static logical lrnd;
- real a, b, c__, f;
- static integer lbeta;
- real savec;
- static logical lieee1;
- real t1, t2;
- extern real slamc3_(real *, real *);
- static integer lt;
- real one, qtr;
-
-
- /* -- LAPACK auxiliary routine (version 3.7.0) -- */
- /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
- /* November 2010 */
-
- /* ===================================================================== */
-
-
- if (first) {
- one = 1.f;
-
- /* LBETA, LIEEE1, LT and LRND are the local values of BETA, */
- /* IEEE1, T and RND. */
-
- /* Throughout this routine we use the function SLAMC3 to ensure */
- /* that relevant values are stored and not held in registers, or */
- /* are not affected by optimizers. */
-
- /* Compute a = 2.0**m with the smallest positive integer m such */
- /* that */
-
- /* fl( a + 1.0 ) = a. */
-
- a = 1.f;
- c__ = 1.f;
-
- /* + WHILE( C.EQ.ONE )LOOP */
- L10:
- if (c__ == one) {
- a *= 2;
- c__ = slamc3_(&a, &one);
- r__1 = -a;
- c__ = slamc3_(&c__, &r__1);
- goto L10;
- }
- /* + END WHILE */
-
- /* Now compute b = 2.0**m with the smallest positive integer m */
- /* such that */
-
- /* fl( a + b ) .gt. a. */
-
- b = 1.f;
- c__ = slamc3_(&a, &b);
-
- /* + WHILE( C.EQ.A )LOOP */
- L20:
- if (c__ == a) {
- b *= 2;
- c__ = slamc3_(&a, &b);
- goto L20;
- }
- /* + END WHILE */
-
- /* Now compute the base. a and c are neighbouring floating point */
- /* numbers in the interval ( beta**t, beta**( t + 1 ) ) and so */
- /* their difference is beta. Adding 0.25 to c is to ensure that it */
- /* is truncated to beta and not ( beta - 1 ). */
-
- qtr = one / 4;
- savec = c__;
- r__1 = -a;
- c__ = slamc3_(&c__, &r__1);
- lbeta = c__ + qtr;
-
- /* Now determine whether rounding or chopping occurs, by adding a */
- /* bit less than beta/2 and a bit more than beta/2 to a. */
-
- b = (real) lbeta;
- r__1 = b / 2;
- r__2 = -b / 100;
- f = slamc3_(&r__1, &r__2);
- c__ = slamc3_(&f, &a);
- if (c__ == a) {
- lrnd = TRUE_;
- } else {
- lrnd = FALSE_;
- }
- r__1 = b / 2;
- r__2 = b / 100;
- f = slamc3_(&r__1, &r__2);
- c__ = slamc3_(&f, &a);
- if (lrnd && c__ == a) {
- lrnd = FALSE_;
- }
-
- /* Try and decide whether rounding is done in the IEEE 'round to */
- /* nearest' style. B/2 is half a unit in the last place of the two */
- /* numbers A and SAVEC. Furthermore, A is even, i.e. has last bit */
- /* zero, and SAVEC is odd. Thus adding B/2 to A should not change */
- /* A, but adding B/2 to SAVEC should change SAVEC. */
-
- r__1 = b / 2;
- t1 = slamc3_(&r__1, &a);
- r__1 = b / 2;
- t2 = slamc3_(&r__1, &savec);
- lieee1 = t1 == a && t2 > savec && lrnd;
-
- /* Now find the mantissa, t. It should be the integer part of */
- /* log to the base beta of a, however it is safer to determine t */
- /* by powering. So we find t as the smallest positive integer for */
- /* which */
-
- /* fl( beta**t + 1.0 ) = 1.0. */
-
- lt = 0;
- a = 1.f;
- c__ = 1.f;
-
- /* + WHILE( C.EQ.ONE )LOOP */
- L30:
- if (c__ == one) {
- ++lt;
- a *= lbeta;
- c__ = slamc3_(&a, &one);
- r__1 = -a;
- c__ = slamc3_(&c__, &r__1);
- goto L30;
- }
- /* + END WHILE */
-
- }
-
- *beta = lbeta;
- *t = lt;
- *rnd = lrnd;
- *ieee1 = lieee1;
- first = FALSE_;
- return 0;
-
- /* End of SLAMC1 */
-
- } /* slamc1_ */
-
-
- /* *********************************************************************** */
-
- /* > \brief \b SLAMC2 */
- /* > \details */
- /* > \b Purpose: */
- /* > \verbatim */
- /* > SLAMC2 determines the machine parameters specified in its argument */
- /* > list. */
- /* > \endverbatim */
- /* > \author LAPACK is a software package provided by Univ. of Tennessee, Univ. of California Berkeley, Univ.
- of Colorado Denver and NAG Ltd.. */
- /* > \date April 2012 */
- /* > \ingroup auxOTHERauxiliary */
- /* > */
- /* > \param[out] BETA */
- /* > \verbatim */
- /* > The base of the machine. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] T */
- /* > \verbatim */
- /* > The number of ( BETA ) digits in the mantissa. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RND */
- /* > \verbatim */
- /* > Specifies whether proper rounding ( RND = .TRUE. ) or */
- /* > chopping ( RND = .FALSE. ) occurs in addition. This may not */
- /* > be a reliable guide to the way in which the machine performs */
- /* > its arithmetic. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] EPS */
- /* > \verbatim */
- /* > The smallest positive number such that */
- /* > fl( 1.0 - EPS ) .LT. 1.0, */
- /* > where fl denotes the computed value. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] EMIN */
- /* > \verbatim */
- /* > The minimum exponent before (gradual) underflow occurs. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RMIN */
- /* > \verbatim */
- /* > The smallest normalized number for the machine, given by */
- /* > BASE**( EMIN - 1 ), where BASE is the floating point value */
- /* > of BETA. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] EMAX */
- /* > \verbatim */
- /* > The maximum exponent before overflow occurs. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RMAX */
- /* > \verbatim */
- /* > The largest positive number for the machine, given by */
- /* > BASE**EMAX * ( 1 - EPS ), where BASE is the floating point */
- /* > value of BETA. */
- /* > \endverbatim */
- /* > */
- /* > \details \b Further \b Details */
- /* > \verbatim */
- /* > */
- /* > The computation of EPS is based on a routine PARANOIA by */
- /* > W. Kahan of the University of California at Berkeley. */
- /* > \endverbatim */
- /* Subroutine */ int slamc2_(integer *beta, integer *t, logical *rnd, real *
- eps, integer *emin, real *rmin, integer *emax, real *rmax)
- {
- /* Initialized data */
-
- static logical first = TRUE_;
- static logical iwarn = FALSE_;
-
- /* Format strings */
- static char fmt_9999[] = "(//\002 WARNING. The value EMIN may be incorre"
- "ct:-\002,\002 EMIN = \002,i8,/\002 If, after inspection, the va"
- "lue EMIN looks\002,\002 acceptable please comment out \002,/\002"
- " the IF block as marked within the code of routine\002,\002 SLAM"
- "C2,\002,/\002 otherwise supply EMIN explicitly.\002,/)";
-
- /* System generated locals */
- integer i__1;
- real r__1, r__2, r__3, r__4, r__5;
-
- /* Local variables */
- logical ieee;
- real half;
- logical lrnd;
- static real leps;
- real zero, a, b, c__;
- integer i__;
- static integer lbeta;
- real rbase;
- static integer lemin, lemax;
- integer gnmin;
- real small;
- integer gpmin;
- real third;
- static real lrmin, lrmax;
- real sixth;
- logical lieee1;
- extern /* Subroutine */ int slamc1_(integer *, integer *, logical *,
- logical *);
- extern real slamc3_(real *, real *);
- extern /* Subroutine */ int slamc4_(integer *, real *, integer *),
- slamc5_(integer *, integer *, integer *, logical *, integer *,
- real *);
- static integer lt;
- integer ngnmin, ngpmin;
- real one, two;
-
- /* Fortran I/O blocks */
- static cilist io___58 = { 0, 6, 0, fmt_9999, 0 };
-
-
-
- /* -- LAPACK auxiliary routine (version 3.7.0) -- */
- /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
- /* November 2010 */
-
- /* ===================================================================== */
-
-
- if (first) {
- zero = 0.f;
- one = 1.f;
- two = 2.f;
-
- /* LBETA, LT, LRND, LEPS, LEMIN and LRMIN are the local values of */
- /* BETA, T, RND, EPS, EMIN and RMIN. */
-
- /* Throughout this routine we use the function SLAMC3 to ensure */
- /* that relevant values are stored and not held in registers, or */
- /* are not affected by optimizers. */
-
- /* SLAMC1 returns the parameters LBETA, LT, LRND and LIEEE1. */
-
- slamc1_(&lbeta, <, &lrnd, &lieee1);
-
- /* Start to find EPS. */
-
- b = (real) lbeta;
- i__1 = -lt;
- a = pow_ri(&b, &i__1);
- leps = a;
-
- /* Try some tricks to see whether or not this is the correct EPS. */
-
- b = two / 3;
- half = one / 2;
- r__1 = -half;
- sixth = slamc3_(&b, &r__1);
- third = slamc3_(&sixth, &sixth);
- r__1 = -half;
- b = slamc3_(&third, &r__1);
- b = slamc3_(&b, &sixth);
- b = abs(b);
- if (b < leps) {
- b = leps;
- }
-
- leps = 1.f;
-
- /* + WHILE( ( LEPS.GT.B ).AND.( B.GT.ZERO ) )LOOP */
- L10:
- if (leps > b && b > zero) {
- leps = b;
- r__1 = half * leps;
- /* Computing 5th power */
- r__3 = two, r__4 = r__3, r__3 *= r__3;
- /* Computing 2nd power */
- r__5 = leps;
- r__2 = r__4 * (r__3 * r__3) * (r__5 * r__5);
- c__ = slamc3_(&r__1, &r__2);
- r__1 = -c__;
- c__ = slamc3_(&half, &r__1);
- b = slamc3_(&half, &c__);
- r__1 = -b;
- c__ = slamc3_(&half, &r__1);
- b = slamc3_(&half, &c__);
- goto L10;
- }
- /* + END WHILE */
-
- if (a < leps) {
- leps = a;
- }
-
- /* Computation of EPS complete. */
-
- /* Now find EMIN. Let A = + or - 1, and + or - (1 + BASE**(-3)). */
- /* Keep dividing A by BETA until (gradual) underflow occurs. This */
- /* is detected when we cannot recover the previous A. */
-
- rbase = one / lbeta;
- small = one;
- for (i__ = 1; i__ <= 3; ++i__) {
- r__1 = small * rbase;
- small = slamc3_(&r__1, &zero);
- /* L20: */
- }
- a = slamc3_(&one, &small);
- slamc4_(&ngpmin, &one, &lbeta);
- r__1 = -one;
- slamc4_(&ngnmin, &r__1, &lbeta);
- slamc4_(&gpmin, &a, &lbeta);
- r__1 = -a;
- slamc4_(&gnmin, &r__1, &lbeta);
- ieee = FALSE_;
-
- if (ngpmin == ngnmin && gpmin == gnmin) {
- if (ngpmin == gpmin) {
- lemin = ngpmin;
- /* ( Non twos-complement machines, no gradual underflow; */
- /* e.g., VAX ) */
- } else if (gpmin - ngpmin == 3) {
- lemin = ngpmin - 1 + lt;
- ieee = TRUE_;
- /* ( Non twos-complement machines, with gradual underflow; */
- /* e.g., IEEE standard followers ) */
- } else {
- lemin = f2cmin(ngpmin,gpmin);
- /* ( A guess; no known machine ) */
- iwarn = TRUE_;
- }
-
- } else if (ngpmin == gpmin && ngnmin == gnmin) {
- if ((i__1 = ngpmin - ngnmin, abs(i__1)) == 1) {
- lemin = f2cmax(ngpmin,ngnmin);
- /* ( Twos-complement machines, no gradual underflow; */
- /* e.g., CYBER 205 ) */
- } else {
- lemin = f2cmin(ngpmin,ngnmin);
- /* ( A guess; no known machine ) */
- iwarn = TRUE_;
- }
-
- } else if ((i__1 = ngpmin - ngnmin, abs(i__1)) == 1 && gpmin == gnmin)
- {
- if (gpmin - f2cmin(ngpmin,ngnmin) == 3) {
- lemin = f2cmax(ngpmin,ngnmin) - 1 + lt;
- /* ( Twos-complement machines with gradual underflow; */
- /* no known machine ) */
- } else {
- lemin = f2cmin(ngpmin,ngnmin);
- /* ( A guess; no known machine ) */
- iwarn = TRUE_;
- }
-
- } else {
- /* Computing MIN */
- i__1 = f2cmin(ngpmin,ngnmin), i__1 = f2cmin(i__1,gpmin);
- lemin = f2cmin(i__1,gnmin);
- /* ( A guess; no known machine ) */
- iwarn = TRUE_;
- }
- first = FALSE_;
- /* ** */
- /* Comment out this if block if EMIN is ok */
- /*
- if (iwarn) {
- first = TRUE_;
- s_wsfe(&io___58);
- do_fio(&c__1, (char *)&lemin, (ftnlen)sizeof(integer));
- e_wsfe();
- }
- */
- /* ** */
-
- /* Assume IEEE arithmetic if we found denormalised numbers above, */
- /* or if arithmetic seems to round in the IEEE style, determined */
- /* in routine SLAMC1. A true IEEE machine should have both things */
- /* true; however, faulty machines may have one or the other. */
-
- ieee = ieee || lieee1;
-
- /* Compute RMIN by successive division by BETA. We could compute */
- /* RMIN as BASE**( EMIN - 1 ), but some machines underflow during */
- /* this computation. */
-
- lrmin = 1.f;
- i__1 = 1 - lemin;
- for (i__ = 1; i__ <= i__1; ++i__) {
- r__1 = lrmin * rbase;
- lrmin = slamc3_(&r__1, &zero);
- /* L30: */
- }
-
- /* Finally, call SLAMC5 to compute EMAX and RMAX. */
-
- slamc5_(&lbeta, <, &lemin, &ieee, &lemax, &lrmax);
- }
-
- *beta = lbeta;
- *t = lt;
- *rnd = lrnd;
- *eps = leps;
- *emin = lemin;
- *rmin = lrmin;
- *emax = lemax;
- *rmax = lrmax;
-
- return 0;
-
-
- /* End of SLAMC2 */
-
- } /* slamc2_ */
-
-
- /* *********************************************************************** */
-
- /* > \brief \b SLAMC3 */
- /* > \details */
- /* > \b Purpose: */
- /* > \verbatim */
- /* > SLAMC3 is intended to force A and B to be stored prior to doing */
- /* > the addition of A and B , for use in situations where optimizers */
- /* > might hold one of these in a register. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] A */
- /* > */
- /* > \param[in] B */
- /* > \verbatim */
- /* > The values A and B. */
- /* > \endverbatim */
- real slamc3_(real *a, real *b)
- {
- /* System generated locals */
- real ret_val;
-
-
- /* -- LAPACK auxiliary routine (version 3.7.0) -- */
- /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
- /* November 2010 */
-
- /* ===================================================================== */
-
-
- ret_val = *a + *b;
-
- return ret_val;
-
- /* End of SLAMC3 */
-
- } /* slamc3_ */
-
-
- /* *********************************************************************** */
-
- /* > \brief \b SLAMC4 */
- /* > \details */
- /* > \b Purpose: */
- /* > \verbatim */
- /* > SLAMC4 is a service routine for SLAMC2. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] EMIN */
- /* > \verbatim */
- /* > The minimum exponent before (gradual) underflow, computed by */
- /* > setting A = START and dividing by BASE until the previous A */
- /* > can not be recovered. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] START */
- /* > \verbatim */
- /* > The starting point for determining EMIN. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] BASE */
- /* > \verbatim */
- /* > The base of the machine. */
- /* > \endverbatim */
- /* > */
- /* Subroutine */ int slamc4_(integer *emin, real *start, integer *base)
- {
- /* System generated locals */
- integer i__1;
- real r__1;
-
- /* Local variables */
- real zero, a;
- integer i__;
- real rbase, b1, b2, c1, c2, d1, d2;
- extern real slamc3_(real *, real *);
- real one;
-
-
- /* -- LAPACK auxiliary routine (version 3.7.0) -- */
- /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
- /* November 2010 */
-
- /* ===================================================================== */
-
-
- a = *start;
- one = 1.f;
- rbase = one / *base;
- zero = 0.f;
- *emin = 1;
- r__1 = a * rbase;
- b1 = slamc3_(&r__1, &zero);
- c1 = a;
- c2 = a;
- d1 = a;
- d2 = a;
- /* + WHILE( ( C1.EQ.A ).AND.( C2.EQ.A ).AND. */
- /* $ ( D1.EQ.A ).AND.( D2.EQ.A ) )LOOP */
- L10:
- if (c1 == a && c2 == a && d1 == a && d2 == a) {
- --(*emin);
- a = b1;
- r__1 = a / *base;
- b1 = slamc3_(&r__1, &zero);
- r__1 = b1 * *base;
- c1 = slamc3_(&r__1, &zero);
- d1 = zero;
- i__1 = *base;
- for (i__ = 1; i__ <= i__1; ++i__) {
- d1 += b1;
- /* L20: */
- }
- r__1 = a * rbase;
- b2 = slamc3_(&r__1, &zero);
- r__1 = b2 / rbase;
- c2 = slamc3_(&r__1, &zero);
- d2 = zero;
- i__1 = *base;
- for (i__ = 1; i__ <= i__1; ++i__) {
- d2 += b2;
- /* L30: */
- }
- goto L10;
- }
- /* + END WHILE */
-
- return 0;
-
- /* End of SLAMC4 */
-
- } /* slamc4_ */
-
-
- /* *********************************************************************** */
-
- /* > \brief \b SLAMC5 */
- /* > \details */
- /* > \b Purpose: */
- /* > \verbatim */
- /* > SLAMC5 attempts to compute RMAX, the largest machine floating-point */
- /* > number, without overflow. It assumes that EMAX + abs(EMIN) sum */
- /* > approximately to a power of 2. It will fail on machines where this */
- /* > assumption does not hold, for example, the Cyber 205 (EMIN = -28625, */
- /* > EMAX = 28718). It will also fail if the value supplied for EMIN is */
- /* > too large (i.e. too close to zero), probably with overflow. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] BETA */
- /* > \verbatim */
- /* > The base of floating-point arithmetic. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] P */
- /* > \verbatim */
- /* > The number of base BETA digits in the mantissa of a */
- /* > floating-point value. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] EMIN */
- /* > \verbatim */
- /* > The minimum exponent before (gradual) underflow. */
- /* > \endverbatim */
- /* > */
- /* > \param[in] IEEE */
- /* > \verbatim */
- /* > A logical flag specifying whether or not the arithmetic */
- /* > system is thought to comply with the IEEE standard. */
- /* > \endverbatim */
- /* > */
- /* > \param[out] EMAX */
- /* > \verbatim */
- /* > The largest exponent before overflow */
- /* > \endverbatim */
- /* > */
- /* > \param[out] RMAX */
- /* > \verbatim */
- /* > The largest machine floating-point number. */
- /* > \endverbatim */
- /* > */
- /* Subroutine */ int slamc5_(integer *beta, integer *p, integer *emin,
- logical *ieee, integer *emax, real *rmax)
- {
- /* System generated locals */
- integer i__1;
- real r__1;
-
- /* Local variables */
- integer lexp;
- real oldy;
- integer uexp, i__;
- real y, z__;
- integer nbits;
- extern real slamc3_(real *, real *);
- real recbas;
- integer exbits, expsum, try__;
-
-
- /* -- LAPACK auxiliary routine (version 3.7.0) -- */
- /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
- /* November 2010 */
-
- /* ===================================================================== */
-
-
- /* First compute LEXP and UEXP, two powers of 2 that bound */
- /* abs(EMIN). We then assume that EMAX + abs(EMIN) will sum */
- /* approximately to the bound that is closest to abs(EMIN). */
- /* (EMAX is the exponent of the required number RMAX). */
-
- lexp = 1;
- exbits = 1;
- L10:
- try__ = lexp << 1;
- if (try__ <= -(*emin)) {
- lexp = try__;
- ++exbits;
- goto L10;
- }
- if (lexp == -(*emin)) {
- uexp = lexp;
- } else {
- uexp = try__;
- ++exbits;
- }
-
- /* Now -LEXP is less than or equal to EMIN, and -UEXP is greater */
- /* than or equal to EMIN. EXBITS is the number of bits needed to */
- /* store the exponent. */
-
- if (uexp + *emin > -lexp - *emin) {
- expsum = lexp << 1;
- } else {
- expsum = uexp << 1;
- }
-
- /* EXPSUM is the exponent range, approximately equal to */
- /* EMAX - EMIN + 1 . */
-
- *emax = expsum + *emin - 1;
- nbits = exbits + 1 + *p;
-
- /* NBITS is the total number of bits needed to store a */
- /* floating-point number. */
-
- if (nbits % 2 == 1 && *beta == 2) {
-
- /* Either there are an odd number of bits used to store a */
- /* floating-point number, which is unlikely, or some bits are */
- /* not used in the representation of numbers, which is possible, */
- /* (e.g. Cray machines) or the mantissa has an implicit bit, */
- /* (e.g. IEEE machines, Dec Vax machines), which is perhaps the */
- /* most likely. We have to assume the last alternative. */
- /* If this is true, then we need to reduce EMAX by one because */
- /* there must be some way of representing zero in an implicit-bit */
- /* system. On machines like Cray, we are reducing EMAX by one */
- /* unnecessarily. */
-
- --(*emax);
- }
-
- if (*ieee) {
-
- /* Assume we are on an IEEE machine which reserves one exponent */
- /* for infinity and NaN. */
-
- --(*emax);
- }
-
- /* Now create RMAX, the largest machine number, which should */
- /* be equal to (1.0 - BETA**(-P)) * BETA**EMAX . */
-
- /* First compute 1.0 - BETA**(-P), being careful that the */
- /* result is less than 1.0 . */
-
- recbas = 1.f / *beta;
- z__ = *beta - 1.f;
- y = 0.f;
- i__1 = *p;
- for (i__ = 1; i__ <= i__1; ++i__) {
- z__ *= recbas;
- if (y < 1.f) {
- oldy = y;
- }
- y = slamc3_(&y, &z__);
- /* L20: */
- }
- if (y >= 1.f) {
- y = oldy;
- }
-
- /* Now multiply by BETA**EMAX to get RMAX. */
-
- i__1 = *emax;
- for (i__ = 1; i__ <= i__1; ++i__) {
- r__1 = y * *beta;
- y = slamc3_(&r__1, &c_b32);
- /* L30: */
- }
-
- *rmax = y;
- return 0;
-
- /* End of SLAMC5 */
-
- } /* slamc5_ */
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