Use f2c translations of LAPACK when no Fortran compiler is available (#3539)
* Add C equivalents of the Fortran routines from Reference-LAPACK as fallbacks, and C_LAPACK variable to trigger their use
This commit is contained in:
Martin Kroeker
GitHub
666
lapack-netlib/SRC/slarrk.c
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666
lapack-netlib/SRC/slarrk.c
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/* f2c.h -- Standard Fortran to C header file */
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/** barf [ba:rf] 2. "He suggested using FORTRAN, and everybody barfed."
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- From The Shogakukan DICTIONARY OF NEW ENGLISH (Second edition) */
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#ifndef F2C_INCLUDE
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#define F2C_INCLUDE
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#include <math.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdio.h>
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#include <complex.h>
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#ifdef complex
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#undef complex
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#endif
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#ifdef I
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#undef I
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#endif
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#if defined(_WIN64)
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typedef long long BLASLONG;
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typedef unsigned long long BLASULONG;
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#else
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typedef long BLASLONG;
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typedef unsigned long BLASULONG;
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#endif
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#ifdef LAPACK_ILP64
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typedef BLASLONG blasint;
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#if defined(_WIN64)
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#define blasabs(x) llabs(x)
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#else
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#define blasabs(x) labs(x)
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#endif
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#else
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typedef int blasint;
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#define blasabs(x) abs(x)
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#endif
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typedef blasint integer;
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typedef unsigned int uinteger;
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typedef char *address;
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typedef short int shortint;
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typedef float real;
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typedef double doublereal;
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typedef struct { real r, i; } complex;
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typedef struct { doublereal r, i; } doublecomplex;
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static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
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static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
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static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
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static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
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#define pCf(z) (*_pCf(z))
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#define pCd(z) (*_pCd(z))
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typedef int logical;
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typedef short int shortlogical;
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typedef char logical1;
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typedef char integer1;
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#define TRUE_ (1)
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#define FALSE_ (0)
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/* Extern is for use with -E */
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#ifndef Extern
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#define Extern extern
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#endif
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/* I/O stuff */
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typedef int flag;
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typedef int ftnlen;
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typedef int ftnint;
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/*external read, write*/
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typedef struct
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{ flag cierr;
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ftnint ciunit;
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flag ciend;
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char *cifmt;
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ftnint cirec;
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} cilist;
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/*internal read, write*/
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typedef struct
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{ flag icierr;
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char *iciunit;
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flag iciend;
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char *icifmt;
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ftnint icirlen;
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ftnint icirnum;
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} icilist;
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/*open*/
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typedef struct
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{ flag oerr;
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ftnint ounit;
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char *ofnm;
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ftnlen ofnmlen;
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char *osta;
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char *oacc;
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char *ofm;
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ftnint orl;
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char *oblnk;
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} olist;
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/*close*/
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typedef struct
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{ flag cerr;
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ftnint cunit;
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char *csta;
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} cllist;
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/*rewind, backspace, endfile*/
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typedef struct
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{ flag aerr;
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ftnint aunit;
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} alist;
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/* inquire */
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typedef struct
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{ flag inerr;
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ftnint inunit;
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char *infile;
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ftnlen infilen;
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ftnint *inex; /*parameters in standard's order*/
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ftnint *inopen;
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ftnint *innum;
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ftnint *innamed;
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char *inname;
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ftnlen innamlen;
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char *inacc;
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ftnlen inacclen;
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char *inseq;
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ftnlen inseqlen;
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char *indir;
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ftnlen indirlen;
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char *infmt;
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ftnlen infmtlen;
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char *inform;
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ftnint informlen;
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char *inunf;
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ftnlen inunflen;
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ftnint *inrecl;
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ftnint *innrec;
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char *inblank;
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ftnlen inblanklen;
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} inlist;
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#define VOID void
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union Multitype { /* for multiple entry points */
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integer1 g;
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shortint h;
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integer i;
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/* longint j; */
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real r;
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doublereal d;
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complex c;
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doublecomplex z;
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};
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typedef union Multitype Multitype;
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struct Vardesc { /* for Namelist */
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char *name;
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char *addr;
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ftnlen *dims;
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int type;
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};
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typedef struct Vardesc Vardesc;
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struct Namelist {
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char *name;
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Vardesc **vars;
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int nvars;
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};
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typedef struct Namelist Namelist;
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#define abs(x) ((x) >= 0 ? (x) : -(x))
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#define dabs(x) (fabs(x))
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#define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
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#define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
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#define dmin(a,b) (f2cmin(a,b))
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#define dmax(a,b) (f2cmax(a,b))
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#define bit_test(a,b) ((a) >> (b) & 1)
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#define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
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#define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
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#define abort_() { sig_die("Fortran abort routine called", 1); }
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#define c_abs(z) (cabsf(Cf(z)))
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#define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
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#define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
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#define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
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#define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
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#define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
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#define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
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//#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
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#define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
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#define d_abs(x) (fabs(*(x)))
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#define d_acos(x) (acos(*(x)))
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#define d_asin(x) (asin(*(x)))
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#define d_atan(x) (atan(*(x)))
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#define d_atn2(x, y) (atan2(*(x),*(y)))
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#define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
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#define r_cnjg(R, Z) { pCf(R) = conj(Cf(Z)); }
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#define d_cos(x) (cos(*(x)))
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#define d_cosh(x) (cosh(*(x)))
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#define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
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#define d_exp(x) (exp(*(x)))
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#define d_imag(z) (cimag(Cd(z)))
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#define r_imag(z) (cimag(Cf(z)))
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#define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
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#define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
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#define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
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#define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
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#define d_log(x) (log(*(x)))
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#define d_mod(x, y) (fmod(*(x), *(y)))
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#define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
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#define d_nint(x) u_nint(*(x))
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#define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
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#define d_sign(a,b) u_sign(*(a),*(b))
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#define r_sign(a,b) u_sign(*(a),*(b))
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#define d_sin(x) (sin(*(x)))
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#define d_sinh(x) (sinh(*(x)))
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#define d_sqrt(x) (sqrt(*(x)))
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#define d_tan(x) (tan(*(x)))
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#define d_tanh(x) (tanh(*(x)))
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#define i_abs(x) abs(*(x))
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#define i_dnnt(x) ((integer)u_nint(*(x)))
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#define i_len(s, n) (n)
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#define i_nint(x) ((integer)u_nint(*(x)))
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#define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
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#define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
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#define pow_si(B,E) spow_ui(*(B),*(E))
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#define pow_ri(B,E) spow_ui(*(B),*(E))
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#define pow_di(B,E) dpow_ui(*(B),*(E))
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#define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
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#define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
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#define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
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#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++ = ' '; }
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#define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
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#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]; }
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#define sig_die(s, kill) { exit(1); }
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#define s_stop(s, n) {exit(0);}
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static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
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#define z_abs(z) (cabs(Cd(z)))
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#define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
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#define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
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#define myexit_() break;
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#define mycycle() continue;
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#define myceiling(w) {ceil(w)}
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#define myhuge(w) {HUGE_VAL}
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//#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
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#define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
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/* procedure parameter types for -A and -C++ */
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#define F2C_proc_par_types 1
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#ifdef __cplusplus
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typedef logical (*L_fp)(...);
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#else
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typedef logical (*L_fp)();
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#endif
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static float spow_ui(float x, integer n) {
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float pow=1.0; unsigned long int u;
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if(n != 0) {
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if(n < 0) n = -n, x = 1/x;
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for(u = n; ; ) {
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if(u & 01) pow *= x;
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if(u >>= 1) x *= x;
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else break;
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}
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}
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return pow;
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}
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static double dpow_ui(double x, integer n) {
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double pow=1.0; unsigned long int u;
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if(n != 0) {
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if(n < 0) n = -n, x = 1/x;
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for(u = n; ; ) {
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if(u & 01) pow *= x;
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if(u >>= 1) x *= x;
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else break;
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}
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}
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return pow;
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}
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static _Complex float cpow_ui(_Complex float x, integer n) {
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_Complex float pow=1.0; unsigned long int u;
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if(n != 0) {
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if(n < 0) n = -n, x = 1/x;
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for(u = n; ; ) {
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if(u & 01) pow *= x;
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if(u >>= 1) x *= x;
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else break;
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}
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}
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return pow;
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}
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static _Complex double zpow_ui(_Complex double x, integer n) {
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_Complex double pow=1.0; unsigned long int u;
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if(n != 0) {
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if(n < 0) n = -n, x = 1/x;
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for(u = n; ; ) {
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if(u & 01) pow *= x;
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if(u >>= 1) x *= x;
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else break;
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}
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}
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return pow;
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}
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static integer pow_ii(integer x, integer n) {
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integer pow; unsigned long int u;
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if (n <= 0) {
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if (n == 0 || x == 1) pow = 1;
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else if (x != -1) pow = x == 0 ? 1/x : 0;
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else n = -n;
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}
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if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
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u = n;
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for(pow = 1; ; ) {
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if(u & 01) pow *= x;
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if(u >>= 1) x *= x;
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else break;
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}
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}
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return pow;
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}
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static integer dmaxloc_(double *w, integer s, integer e, integer *n)
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{
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double m; integer i, mi;
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for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
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if (w[i-1]>m) mi=i ,m=w[i-1];
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return mi-s+1;
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}
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static integer smaxloc_(float *w, integer s, integer e, integer *n)
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{
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float m; integer i, mi;
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for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
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if (w[i-1]>m) mi=i ,m=w[i-1];
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return mi-s+1;
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}
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static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
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integer n = *n_, incx = *incx_, incy = *incy_, i;
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_Complex float zdotc = 0.0;
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if (incx == 1 && incy == 1) {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
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}
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} else {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
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}
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}
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pCf(z) = zdotc;
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}
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static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
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integer n = *n_, incx = *incx_, incy = *incy_, i;
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_Complex double zdotc = 0.0;
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if (incx == 1 && incy == 1) {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
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}
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} else {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
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}
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}
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pCd(z) = zdotc;
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}
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static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
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integer n = *n_, incx = *incx_, incy = *incy_, i;
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_Complex float zdotc = 0.0;
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if (incx == 1 && incy == 1) {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += Cf(&x[i]) * Cf(&y[i]);
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}
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} else {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
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}
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}
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pCf(z) = zdotc;
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}
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static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
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integer n = *n_, incx = *incx_, incy = *incy_, i;
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_Complex double zdotc = 0.0;
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if (incx == 1 && incy == 1) {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += Cd(&x[i]) * Cd(&y[i]);
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}
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} else {
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for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
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zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
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}
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}
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pCd(z) = zdotc;
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}
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#endif
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/* -- translated by f2c (version 20000121).
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You must link the resulting object file with the libraries:
|
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-lf2c -lm (in that order)
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*/
|
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|
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/* > \brief \b SLARRK computes one eigenvalue of a symmetric tridiagonal matrix T to suitable accuracy. */
|
||||
|
||||
/* =========== DOCUMENTATION =========== */
|
||||
|
||||
/* Online html documentation available at */
|
||||
/* http://www.netlib.org/lapack/explore-html/ */
|
||||
|
||||
/* > \htmlonly */
|
||||
/* > Download SLARRK + dependencies */
|
||||
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/slarrk.
|
||||
f"> */
|
||||
/* > [TGZ]</a> */
|
||||
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/slarrk.
|
||||
f"> */
|
||||
/* > [ZIP]</a> */
|
||||
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/slarrk.
|
||||
f"> */
|
||||
/* > [TXT]</a> */
|
||||
/* > \endhtmlonly */
|
||||
|
||||
/* Definition: */
|
||||
/* =========== */
|
||||
|
||||
/* SUBROUTINE SLARRK( N, IW, GL, GU, */
|
||||
/* D, E2, PIVMIN, RELTOL, W, WERR, INFO) */
|
||||
|
||||
/* INTEGER INFO, IW, N */
|
||||
/* REAL PIVMIN, RELTOL, GL, GU, W, WERR */
|
||||
/* REAL D( * ), E2( * ) */
|
||||
|
||||
|
||||
/* > \par Purpose: */
|
||||
/* ============= */
|
||||
/* > */
|
||||
/* > \verbatim */
|
||||
/* > */
|
||||
/* > SLARRK computes one eigenvalue of a symmetric tridiagonal */
|
||||
/* > matrix T to suitable accuracy. This is an auxiliary code to be */
|
||||
/* > called from SSTEMR. */
|
||||
/* > */
|
||||
/* > To avoid overflow, the matrix must be scaled so that its */
|
||||
/* > largest element is no greater than overflow**(1/2) * underflow**(1/4) in absolute value, and for greatest
|
||||
*/
|
||||
/* > accuracy, it should not be much smaller than that. */
|
||||
/* > */
|
||||
/* > See W. Kahan "Accurate Eigenvalues of a Symmetric Tridiagonal */
|
||||
/* > Matrix", Report CS41, Computer Science Dept., Stanford */
|
||||
/* > University, July 21, 1966. */
|
||||
/* > \endverbatim */
|
||||
|
||||
/* Arguments: */
|
||||
/* ========== */
|
||||
|
||||
/* > \param[in] N */
|
||||
/* > \verbatim */
|
||||
/* > N is INTEGER */
|
||||
/* > The order of the tridiagonal matrix T. N >= 0. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] IW */
|
||||
/* > \verbatim */
|
||||
/* > IW is INTEGER */
|
||||
/* > The index of the eigenvalues to be returned. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] GL */
|
||||
/* > \verbatim */
|
||||
/* > GL is REAL */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] GU */
|
||||
/* > \verbatim */
|
||||
/* > GU is REAL */
|
||||
/* > An upper and a lower bound on the eigenvalue. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] D */
|
||||
/* > \verbatim */
|
||||
/* > D is REAL array, dimension (N) */
|
||||
/* > The n diagonal elements of the tridiagonal matrix T. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] E2 */
|
||||
/* > \verbatim */
|
||||
/* > E2 is REAL array, dimension (N-1) */
|
||||
/* > The (n-1) squared off-diagonal elements of the tridiagonal matrix T. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] PIVMIN */
|
||||
/* > \verbatim */
|
||||
/* > PIVMIN is REAL */
|
||||
/* > The minimum pivot allowed in the Sturm sequence for T. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] RELTOL */
|
||||
/* > \verbatim */
|
||||
/* > RELTOL is REAL */
|
||||
/* > The minimum relative width of an interval. When an interval */
|
||||
/* > is narrower than RELTOL times the larger (in */
|
||||
/* > magnitude) endpoint, then it is considered to be */
|
||||
/* > sufficiently small, i.e., converged. Note: this should */
|
||||
/* > always be at least radix*machine epsilon. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[out] W */
|
||||
/* > \verbatim */
|
||||
/* > W is REAL */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[out] WERR */
|
||||
/* > \verbatim */
|
||||
/* > WERR is REAL */
|
||||
/* > The error bound on the corresponding eigenvalue approximation */
|
||||
/* > in W. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[out] INFO */
|
||||
/* > \verbatim */
|
||||
/* > INFO is INTEGER */
|
||||
/* > = 0: Eigenvalue converged */
|
||||
/* > = -1: Eigenvalue did NOT converge */
|
||||
/* > \endverbatim */
|
||||
|
||||
/* > \par Internal Parameters: */
|
||||
/* ========================= */
|
||||
/* > */
|
||||
/* > \verbatim */
|
||||
/* > FUDGE REAL , default = 2 */
|
||||
/* > A "fudge factor" to widen the Gershgorin intervals. */
|
||||
/* > \endverbatim */
|
||||
|
||||
/* Authors: */
|
||||
/* ======== */
|
||||
|
||||
/* > \author Univ. of Tennessee */
|
||||
/* > \author Univ. of California Berkeley */
|
||||
/* > \author Univ. of Colorado Denver */
|
||||
/* > \author NAG Ltd. */
|
||||
|
||||
/* > \date June 2017 */
|
||||
|
||||
/* > \ingroup OTHERauxiliary */
|
||||
|
||||
/* ===================================================================== */
|
||||
/* Subroutine */ int slarrk_(integer *n, integer *iw, real *gl, real *gu,
|
||||
real *d__, real *e2, real *pivmin, real *reltol, real *w, real *werr,
|
||||
integer *info)
|
||||
{
|
||||
/* System generated locals */
|
||||
integer i__1;
|
||||
real r__1, r__2;
|
||||
|
||||
/* Local variables */
|
||||
real left;
|
||||
integer i__;
|
||||
real atoli, right;
|
||||
integer itmax;
|
||||
real rtoli, tnorm;
|
||||
integer it;
|
||||
extern real slamch_(char *);
|
||||
integer negcnt;
|
||||
real mid, eps, tmp1, tmp2;
|
||||
|
||||
|
||||
/* -- LAPACK auxiliary routine (version 3.7.1) -- */
|
||||
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
|
||||
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
|
||||
/* June 2017 */
|
||||
|
||||
|
||||
/* ===================================================================== */
|
||||
|
||||
|
||||
/* Quick return if possible */
|
||||
|
||||
/* Parameter adjustments */
|
||||
--e2;
|
||||
--d__;
|
||||
|
||||
/* Function Body */
|
||||
if (*n <= 0) {
|
||||
*info = 0;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Get machine constants */
|
||||
eps = slamch_("P");
|
||||
/* Computing MAX */
|
||||
r__1 = abs(*gl), r__2 = abs(*gu);
|
||||
tnorm = f2cmax(r__1,r__2);
|
||||
rtoli = *reltol;
|
||||
atoli = *pivmin * 4.f;
|
||||
itmax = (integer) ((log(tnorm + *pivmin) - log(*pivmin)) / log(2.f)) + 2;
|
||||
*info = -1;
|
||||
left = *gl - tnorm * 2.f * eps * *n - *pivmin * 4.f;
|
||||
right = *gu + tnorm * 2.f * eps * *n + *pivmin * 4.f;
|
||||
it = 0;
|
||||
L10:
|
||||
|
||||
/* Check if interval converged or maximum number of iterations reached */
|
||||
|
||||
tmp1 = (r__1 = right - left, abs(r__1));
|
||||
/* Computing MAX */
|
||||
r__1 = abs(right), r__2 = abs(left);
|
||||
tmp2 = f2cmax(r__1,r__2);
|
||||
/* Computing MAX */
|
||||
r__1 = f2cmax(atoli,*pivmin), r__2 = rtoli * tmp2;
|
||||
if (tmp1 < f2cmax(r__1,r__2)) {
|
||||
*info = 0;
|
||||
goto L30;
|
||||
}
|
||||
if (it > itmax) {
|
||||
goto L30;
|
||||
}
|
||||
|
||||
/* Count number of negative pivots for mid-point */
|
||||
|
||||
++it;
|
||||
mid = (left + right) * .5f;
|
||||
negcnt = 0;
|
||||
tmp1 = d__[1] - mid;
|
||||
if (abs(tmp1) < *pivmin) {
|
||||
tmp1 = -(*pivmin);
|
||||
}
|
||||
if (tmp1 <= 0.f) {
|
||||
++negcnt;
|
||||
}
|
||||
|
||||
i__1 = *n;
|
||||
for (i__ = 2; i__ <= i__1; ++i__) {
|
||||
tmp1 = d__[i__] - e2[i__ - 1] / tmp1 - mid;
|
||||
if (abs(tmp1) < *pivmin) {
|
||||
tmp1 = -(*pivmin);
|
||||
}
|
||||
if (tmp1 <= 0.f) {
|
||||
++negcnt;
|
||||
}
|
||||
/* L20: */
|
||||
}
|
||||
if (negcnt >= *iw) {
|
||||
right = mid;
|
||||
} else {
|
||||
left = mid;
|
||||
}
|
||||
goto L10;
|
||||
L30:
|
||||
|
||||
/* Converged or maximum number of iterations reached */
|
||||
|
||||
*w = (left + right) * .5f;
|
||||
*werr = (r__1 = right - left, abs(r__1)) * .5f;
|
||||
return 0;
|
||||
|
||||
/* End of SLARRK */
|
||||
|
||||
} /* slarrk_ */
|
||||
|
||||
Reference in New Issue
Block a user