File: dlar1v.c

package info (click to toggle)
ruby-lapack 1.8.2-1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm, sid, trixie
  • size: 28,572 kB
  • sloc: ansic: 191,612; ruby: 3,937; makefile: 6
file content (173 lines) | stat: -rw-r--r-- 11,110 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
#include "rb_lapack.h"

extern VOID dlar1v_(integer* n, integer* b1, integer* bn, doublereal* lambda, doublereal* d, doublereal* l, doublereal* ld, doublereal* lld, doublereal* pivmin, doublereal* gaptol, doublereal* z, logical* wantnc, integer* negcnt, doublereal* ztz, doublereal* mingma, integer* r, integer* isuppz, doublereal* nrminv, doublereal* resid, doublereal* rqcorr, doublereal* work);


static VALUE
rblapack_dlar1v(int argc, VALUE *argv, VALUE self){
  VALUE rblapack_b1;
  integer b1; 
  VALUE rblapack_bn;
  integer bn; 
  VALUE rblapack_lambda;
  doublereal lambda; 
  VALUE rblapack_d;
  doublereal *d; 
  VALUE rblapack_l;
  doublereal *l; 
  VALUE rblapack_ld;
  doublereal *ld; 
  VALUE rblapack_lld;
  doublereal *lld; 
  VALUE rblapack_pivmin;
  doublereal pivmin; 
  VALUE rblapack_gaptol;
  doublereal gaptol; 
  VALUE rblapack_z;
  doublereal *z; 
  VALUE rblapack_wantnc;
  logical wantnc; 
  VALUE rblapack_r;
  integer r; 
  VALUE rblapack_negcnt;
  integer negcnt; 
  VALUE rblapack_ztz;
  doublereal ztz; 
  VALUE rblapack_mingma;
  doublereal mingma; 
  VALUE rblapack_isuppz;
  integer *isuppz; 
  VALUE rblapack_nrminv;
  doublereal nrminv; 
  VALUE rblapack_resid;
  doublereal resid; 
  VALUE rblapack_rqcorr;
  doublereal rqcorr; 
  VALUE rblapack_z_out__;
  doublereal *z_out__;
  doublereal *work;

  integer n;

  VALUE rblapack_options;
  if (argc > 0 && TYPE(argv[argc-1]) == T_HASH) {
    argc--;
    rblapack_options = argv[argc];
    if (rb_hash_aref(rblapack_options, sHelp) == Qtrue) {
      printf("%s\n", "USAGE:\n  negcnt, ztz, mingma, isuppz, nrminv, resid, rqcorr, z, r = NumRu::Lapack.dlar1v( b1, bn, lambda, d, l, ld, lld, pivmin, gaptol, z, wantnc, r, [:usage => usage, :help => help])\n\n\nFORTRAN MANUAL\n      SUBROUTINE DLAR1V( N, B1, BN, LAMBDA, D, L, LD, LLD, PIVMIN, GAPTOL, Z, WANTNC, NEGCNT, ZTZ, MINGMA, R, ISUPPZ, NRMINV, RESID, RQCORR, WORK )\n\n*  Purpose\n*  =======\n*\n*  DLAR1V computes the (scaled) r-th column of the inverse of\n*  the sumbmatrix in rows B1 through BN of the tridiagonal matrix\n*  L D L^T - sigma I. When sigma is close to an eigenvalue, the\n*  computed vector is an accurate eigenvector. Usually, r corresponds\n*  to the index where the eigenvector is largest in magnitude.\n*  The following steps accomplish this computation :\n*  (a) Stationary qd transform,  L D L^T - sigma I = L(+) D(+) L(+)^T,\n*  (b) Progressive qd transform, L D L^T - sigma I = U(-) D(-) U(-)^T,\n*  (c) Computation of the diagonal elements of the inverse of\n*      L D L^T - sigma I by combining the above transforms, and choosing\n*      r as the index where the diagonal of the inverse is (one of the)\n*      largest in magnitude.\n*  (d) Computation of the (scaled) r-th column of the inverse using the\n*      twisted factorization obtained by combining the top part of the\n*      the stationary and the bottom part of the progressive transform.\n*\n\n*  Arguments\n*  =========\n*\n*  N        (input) INTEGER\n*           The order of the matrix L D L^T.\n*\n*  B1       (input) INTEGER\n*           First index of the submatrix of L D L^T.\n*\n*  BN       (input) INTEGER\n*           Last index of the submatrix of L D L^T.\n*\n*  LAMBDA    (input) DOUBLE PRECISION\n*           The shift. In order to compute an accurate eigenvector,\n*           LAMBDA should be a good approximation to an eigenvalue\n*           of L D L^T.\n*\n*  L        (input) DOUBLE PRECISION array, dimension (N-1)\n*           The (n-1) subdiagonal elements of the unit bidiagonal matrix\n*           L, in elements 1 to N-1.\n*\n*  D        (input) DOUBLE PRECISION array, dimension (N)\n*           The n diagonal elements of the diagonal matrix D.\n*\n*  LD       (input) DOUBLE PRECISION array, dimension (N-1)\n*           The n-1 elements L(i)*D(i).\n*\n*  LLD      (input) DOUBLE PRECISION array, dimension (N-1)\n*           The n-1 elements L(i)*L(i)*D(i).\n*\n*  PIVMIN   (input) DOUBLE PRECISION\n*           The minimum pivot in the Sturm sequence.\n*\n*  GAPTOL   (input) DOUBLE PRECISION\n*           Tolerance that indicates when eigenvector entries are negligible\n*           w.r.t. their contribution to the residual.\n*\n*  Z        (input/output) DOUBLE PRECISION array, dimension (N)\n*           On input, all entries of Z must be set to 0.\n*           On output, Z contains the (scaled) r-th column of the\n*           inverse. The scaling is such that Z(R) equals 1.\n*\n*  WANTNC   (input) LOGICAL\n*           Specifies whether NEGCNT has to be computed.\n*\n*  NEGCNT   (output) INTEGER\n*           If WANTNC is .TRUE. then NEGCNT = the number of pivots < pivmin\n*           in the  matrix factorization L D L^T, and NEGCNT = -1 otherwise.\n*\n*  ZTZ      (output) DOUBLE PRECISION\n*           The square of the 2-norm of Z.\n*\n*  MINGMA   (output) DOUBLE PRECISION\n*           The reciprocal of the largest (in magnitude) diagonal\n*           element of the inverse of L D L^T - sigma I.\n*\n*  R        (input/output) INTEGER\n*           The twist index for the twisted factorization used to\n*           compute Z.\n*           On input, 0 <= R <= N. If R is input as 0, R is set to\n*           the index where (L D L^T - sigma I)^{-1} is largest\n*           in magnitude. If 1 <= R <= N, R is unchanged.\n*           On output, R contains the twist index used to compute Z.\n*           Ideally, R designates the position of the maximum entry in the\n*           eigenvector.\n*\n*  ISUPPZ   (output) INTEGER array, dimension (2)\n*           The support of the vector in Z, i.e., the vector Z is\n*           nonzero only in elements ISUPPZ(1) through ISUPPZ( 2 ).\n*\n*  NRMINV   (output) DOUBLE PRECISION\n*           NRMINV = 1/SQRT( ZTZ )\n*\n*  RESID    (output) DOUBLE PRECISION\n*           The residual of the FP vector.\n*           RESID = ABS( MINGMA )/SQRT( ZTZ )\n*\n*  RQCORR   (output) DOUBLE PRECISION\n*           The Rayleigh Quotient correction to LAMBDA.\n*           RQCORR = MINGMA*TMP\n*\n*  WORK     (workspace) DOUBLE PRECISION array, dimension (4*N)\n*\n\n*  Further Details\n*  ===============\n*\n*  Based on contributions by\n*     Beresford Parlett, University of California, Berkeley, USA\n*     Jim Demmel, University of California, Berkeley, USA\n*     Inderjit Dhillon, University of Texas, Austin, USA\n*     Osni Marques, LBNL/NERSC, USA\n*     Christof Voemel, University of California, Berkeley, USA\n*\n*  =====================================================================\n*\n\n");
      return Qnil;
    }
    if (rb_hash_aref(rblapack_options, sUsage) == Qtrue) {
      printf("%s\n", "USAGE:\n  negcnt, ztz, mingma, isuppz, nrminv, resid, rqcorr, z, r = NumRu::Lapack.dlar1v( b1, bn, lambda, d, l, ld, lld, pivmin, gaptol, z, wantnc, r, [:usage => usage, :help => help])\n");
      return Qnil;
    } 
  } else
    rblapack_options = Qnil;
  if (argc != 12 && argc != 12)
    rb_raise(rb_eArgError,"wrong number of arguments (%d for 12)", argc);
  rblapack_b1 = argv[0];
  rblapack_bn = argv[1];
  rblapack_lambda = argv[2];
  rblapack_d = argv[3];
  rblapack_l = argv[4];
  rblapack_ld = argv[5];
  rblapack_lld = argv[6];
  rblapack_pivmin = argv[7];
  rblapack_gaptol = argv[8];
  rblapack_z = argv[9];
  rblapack_wantnc = argv[10];
  rblapack_r = argv[11];
  if (argc == 12) {
  } else if (rblapack_options != Qnil) {
  } else {
  }

  b1 = NUM2INT(rblapack_b1);
  lambda = NUM2DBL(rblapack_lambda);
  pivmin = NUM2DBL(rblapack_pivmin);
  if (!NA_IsNArray(rblapack_z))
    rb_raise(rb_eArgError, "z (10th argument) must be NArray");
  if (NA_RANK(rblapack_z) != 1)
    rb_raise(rb_eArgError, "rank of z (10th argument) must be %d", 1);
  n = NA_SHAPE0(rblapack_z);
  if (NA_TYPE(rblapack_z) != NA_DFLOAT)
    rblapack_z = na_change_type(rblapack_z, NA_DFLOAT);
  z = NA_PTR_TYPE(rblapack_z, doublereal*);
  r = NUM2INT(rblapack_r);
  bn = NUM2INT(rblapack_bn);
  gaptol = NUM2DBL(rblapack_gaptol);
  if (!NA_IsNArray(rblapack_d))
    rb_raise(rb_eArgError, "d (4th argument) must be NArray");
  if (NA_RANK(rblapack_d) != 1)
    rb_raise(rb_eArgError, "rank of d (4th argument) must be %d", 1);
  if (NA_SHAPE0(rblapack_d) != n)
    rb_raise(rb_eRuntimeError, "shape 0 of d must be the same as shape 0 of z");
  if (NA_TYPE(rblapack_d) != NA_DFLOAT)
    rblapack_d = na_change_type(rblapack_d, NA_DFLOAT);
  d = NA_PTR_TYPE(rblapack_d, doublereal*);
  if (!NA_IsNArray(rblapack_ld))
    rb_raise(rb_eArgError, "ld (6th argument) must be NArray");
  if (NA_RANK(rblapack_ld) != 1)
    rb_raise(rb_eArgError, "rank of ld (6th argument) must be %d", 1);
  if (NA_SHAPE0(rblapack_ld) != (n-1))
    rb_raise(rb_eRuntimeError, "shape 0 of ld must be %d", n-1);
  if (NA_TYPE(rblapack_ld) != NA_DFLOAT)
    rblapack_ld = na_change_type(rblapack_ld, NA_DFLOAT);
  ld = NA_PTR_TYPE(rblapack_ld, doublereal*);
  wantnc = (rblapack_wantnc == Qtrue);
  if (!NA_IsNArray(rblapack_l))
    rb_raise(rb_eArgError, "l (5th argument) must be NArray");
  if (NA_RANK(rblapack_l) != 1)
    rb_raise(rb_eArgError, "rank of l (5th argument) must be %d", 1);
  if (NA_SHAPE0(rblapack_l) != (n-1))
    rb_raise(rb_eRuntimeError, "shape 0 of l must be %d", n-1);
  if (NA_TYPE(rblapack_l) != NA_DFLOAT)
    rblapack_l = na_change_type(rblapack_l, NA_DFLOAT);
  l = NA_PTR_TYPE(rblapack_l, doublereal*);
  if (!NA_IsNArray(rblapack_lld))
    rb_raise(rb_eArgError, "lld (7th argument) must be NArray");
  if (NA_RANK(rblapack_lld) != 1)
    rb_raise(rb_eArgError, "rank of lld (7th argument) must be %d", 1);
  if (NA_SHAPE0(rblapack_lld) != (n-1))
    rb_raise(rb_eRuntimeError, "shape 0 of lld must be %d", n-1);
  if (NA_TYPE(rblapack_lld) != NA_DFLOAT)
    rblapack_lld = na_change_type(rblapack_lld, NA_DFLOAT);
  lld = NA_PTR_TYPE(rblapack_lld, doublereal*);
  {
    na_shape_t shape[1];
    shape[0] = 2;
    rblapack_isuppz = na_make_object(NA_LINT, 1, shape, cNArray);
  }
  isuppz = NA_PTR_TYPE(rblapack_isuppz, integer*);
  {
    na_shape_t shape[1];
    shape[0] = n;
    rblapack_z_out__ = na_make_object(NA_DFLOAT, 1, shape, cNArray);
  }
  z_out__ = NA_PTR_TYPE(rblapack_z_out__, doublereal*);
  MEMCPY(z_out__, z, doublereal, NA_TOTAL(rblapack_z));
  rblapack_z = rblapack_z_out__;
  z = z_out__;
  work = ALLOC_N(doublereal, (4*n));

  dlar1v_(&n, &b1, &bn, &lambda, d, l, ld, lld, &pivmin, &gaptol, z, &wantnc, &negcnt, &ztz, &mingma, &r, isuppz, &nrminv, &resid, &rqcorr, work);

  free(work);
  rblapack_negcnt = INT2NUM(negcnt);
  rblapack_ztz = rb_float_new((double)ztz);
  rblapack_mingma = rb_float_new((double)mingma);
  rblapack_nrminv = rb_float_new((double)nrminv);
  rblapack_resid = rb_float_new((double)resid);
  rblapack_rqcorr = rb_float_new((double)rqcorr);
  rblapack_r = INT2NUM(r);
  return rb_ary_new3(9, rblapack_negcnt, rblapack_ztz, rblapack_mingma, rblapack_isuppz, rblapack_nrminv, rblapack_resid, rblapack_rqcorr, rblapack_z, rblapack_r);
}

void
init_lapack_dlar1v(VALUE mLapack, VALUE sH, VALUE sU, VALUE zero){
  sHelp = sH;
  sUsage = sU;
  rblapack_ZERO = zero;

  rb_define_module_function(mLapack, "dlar1v", rblapack_dlar1v, -1);
}