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#include "rb_lapack.h"
extern VOID zgbequb_(integer* m, integer* n, integer* kl, integer* ku, doublereal* ab, integer* ldab, doublereal* r, doublereal* c, doublereal* rowcnd, doublereal* colcnd, doublereal* amax, integer* info);
static VALUE
rblapack_zgbequb(int argc, VALUE *argv, VALUE self){
VALUE rblapack_kl;
integer kl;
VALUE rblapack_ku;
integer ku;
VALUE rblapack_ab;
doublereal *ab;
VALUE rblapack_r;
doublereal *r;
VALUE rblapack_c;
doublereal *c;
VALUE rblapack_rowcnd;
doublereal rowcnd;
VALUE rblapack_colcnd;
doublereal colcnd;
VALUE rblapack_amax;
doublereal amax;
VALUE rblapack_info;
integer info;
integer ldab;
integer n;
integer m;
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 r, c, rowcnd, colcnd, amax, info = NumRu::Lapack.zgbequb( kl, ku, ab, [:usage => usage, :help => help])\n\n\nFORTRAN MANUAL\n SUBROUTINE ZGBEQUB( M, N, KL, KU, AB, LDAB, R, C, ROWCND, COLCND, AMAX, INFO )\n\n* Purpose\n* =======\n*\n* ZGBEQUB computes row and column scalings intended to equilibrate an\n* M-by-N matrix A and reduce its condition number. R returns the row\n* scale factors and C the column scale factors, chosen to try to make\n* the largest element in each row and column of the matrix B with\n* elements B(i,j)=R(i)*A(i,j)*C(j) have an absolute value of at most\n* the radix.\n*\n* R(i) and C(j) are restricted to be a power of the radix between\n* SMLNUM = smallest safe number and BIGNUM = largest safe number. Use\n* of these scaling factors is not guaranteed to reduce the condition\n* number of A but works well in practice.\n*\n* This routine differs from ZGEEQU by restricting the scaling factors\n* to a power of the radix. Baring over- and underflow, scaling by\n* these factors introduces no additional rounding errors. However, the\n* scaled entries' magnitured are no longer approximately 1 but lie\n* between sqrt(radix) and 1/sqrt(radix).\n*\n\n* Arguments\n* =========\n*\n* M (input) INTEGER\n* The number of rows of the matrix A. M >= 0.\n*\n* N (input) INTEGER\n* The number of columns of the matrix A. N >= 0.\n*\n* KL (input) INTEGER\n* The number of subdiagonals within the band of A. KL >= 0.\n*\n* KU (input) INTEGER\n* The number of superdiagonals within the band of A. KU >= 0.\n*\n* AB (input) DOUBLE PRECISION array, dimension (LDAB,N)\n* On entry, the matrix A in band storage, in rows 1 to KL+KU+1.\n* The j-th column of A is stored in the j-th column of the\n* array AB as follows:\n* AB(KU+1+i-j,j) = A(i,j) for max(1,j-KU)<=i<=min(N,j+kl)\n*\n* LDAB (input) INTEGER\n* The leading dimension of the array A. LDAB >= max(1,M).\n*\n* R (output) DOUBLE PRECISION array, dimension (M)\n* If INFO = 0 or INFO > M, R contains the row scale factors\n* for A.\n*\n* C (output) DOUBLE PRECISION array, dimension (N)\n* If INFO = 0, C contains the column scale factors for A.\n*\n* ROWCND (output) DOUBLE PRECISION\n* If INFO = 0 or INFO > M, ROWCND contains the ratio of the\n* smallest R(i) to the largest R(i). If ROWCND >= 0.1 and\n* AMAX is neither too large nor too small, it is not worth\n* scaling by R.\n*\n* COLCND (output) DOUBLE PRECISION\n* If INFO = 0, COLCND contains the ratio of the smallest\n* C(i) to the largest C(i). If COLCND >= 0.1, it is not\n* worth scaling by C.\n*\n* AMAX (output) DOUBLE PRECISION\n* Absolute value of largest matrix element. If AMAX is very\n* close to overflow or very close to underflow, the matrix\n* should be scaled.\n*\n* INFO (output) INTEGER\n* = 0: successful exit\n* < 0: if INFO = -i, the i-th argument had an illegal value\n* > 0: if INFO = i, and i is\n* <= M: the i-th row of A is exactly zero\n* > M: the (i-M)-th column of A is exactly zero\n*\n\n* =====================================================================\n*\n\n");
return Qnil;
}
if (rb_hash_aref(rblapack_options, sUsage) == Qtrue) {
printf("%s\n", "USAGE:\n r, c, rowcnd, colcnd, amax, info = NumRu::Lapack.zgbequb( kl, ku, ab, [:usage => usage, :help => help])\n");
return Qnil;
}
} else
rblapack_options = Qnil;
if (argc != 3 && argc != 3)
rb_raise(rb_eArgError,"wrong number of arguments (%d for 3)", argc);
rblapack_kl = argv[0];
rblapack_ku = argv[1];
rblapack_ab = argv[2];
if (argc == 3) {
} else if (rblapack_options != Qnil) {
} else {
}
kl = NUM2INT(rblapack_kl);
if (!NA_IsNArray(rblapack_ab))
rb_raise(rb_eArgError, "ab (3th argument) must be NArray");
if (NA_RANK(rblapack_ab) != 2)
rb_raise(rb_eArgError, "rank of ab (3th argument) must be %d", 2);
ldab = NA_SHAPE0(rblapack_ab);
n = NA_SHAPE1(rblapack_ab);
if (NA_TYPE(rblapack_ab) != NA_DFLOAT)
rblapack_ab = na_change_type(rblapack_ab, NA_DFLOAT);
ab = NA_PTR_TYPE(rblapack_ab, doublereal*);
ku = NUM2INT(rblapack_ku);
m = ldab;
{
na_shape_t shape[1];
shape[0] = m;
rblapack_r = na_make_object(NA_DFLOAT, 1, shape, cNArray);
}
r = NA_PTR_TYPE(rblapack_r, doublereal*);
{
na_shape_t shape[1];
shape[0] = n;
rblapack_c = na_make_object(NA_DFLOAT, 1, shape, cNArray);
}
c = NA_PTR_TYPE(rblapack_c, doublereal*);
zgbequb_(&m, &n, &kl, &ku, ab, &ldab, r, c, &rowcnd, &colcnd, &amax, &info);
rblapack_rowcnd = rb_float_new((double)rowcnd);
rblapack_colcnd = rb_float_new((double)colcnd);
rblapack_amax = rb_float_new((double)amax);
rblapack_info = INT2NUM(info);
return rb_ary_new3(6, rblapack_r, rblapack_c, rblapack_rowcnd, rblapack_colcnd, rblapack_amax, rblapack_info);
}
void
init_lapack_zgbequb(VALUE mLapack, VALUE sH, VALUE sU, VALUE zero){
sHelp = sH;
sUsage = sU;
rblapack_ZERO = zero;
rb_define_module_function(mLapack, "zgbequb", rblapack_zgbequb, -1);
}
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