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#include "rb_lapack.h"
extern VOID zpbequ_(char* uplo, integer* n, integer* kd, doublecomplex* ab, integer* ldab, doublereal* s, doublereal* scond, doublereal* amax, integer* info);
static VALUE
rblapack_zpbequ(int argc, VALUE *argv, VALUE self){
VALUE rblapack_uplo;
char uplo;
VALUE rblapack_kd;
integer kd;
VALUE rblapack_ab;
doublecomplex *ab;
VALUE rblapack_s;
doublereal *s;
VALUE rblapack_scond;
doublereal scond;
VALUE rblapack_amax;
doublereal amax;
VALUE rblapack_info;
integer info;
integer ldab;
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 s, scond, amax, info = NumRu::Lapack.zpbequ( uplo, kd, ab, [:usage => usage, :help => help])\n\n\nFORTRAN MANUAL\n SUBROUTINE ZPBEQU( UPLO, N, KD, AB, LDAB, S, SCOND, AMAX, INFO )\n\n* Purpose\n* =======\n*\n* ZPBEQU computes row and column scalings intended to equilibrate a\n* Hermitian positive definite band matrix A and reduce its condition\n* number (with respect to the two-norm). S contains the scale factors,\n* S(i) = 1/sqrt(A(i,i)), chosen so that the scaled matrix B with\n* elements B(i,j) = S(i)*A(i,j)*S(j) has ones on the diagonal. This\n* choice of S puts the condition number of B within a factor N of the\n* smallest possible condition number over all possible diagonal\n* scalings.\n*\n\n* Arguments\n* =========\n*\n* UPLO (input) CHARACTER*1\n* = 'U': Upper triangular of A is stored;\n* = 'L': Lower triangular of A is stored.\n*\n* N (input) INTEGER\n* The order of the matrix A. N >= 0.\n*\n* KD (input) INTEGER\n* The number of superdiagonals of the matrix A if UPLO = 'U',\n* or the number of subdiagonals if UPLO = 'L'. KD >= 0.\n*\n* AB (input) COMPLEX*16 array, dimension (LDAB,N)\n* The upper or lower triangle of the Hermitian band matrix A,\n* stored in the first KD+1 rows of the array. The j-th column\n* of A is stored in the j-th column of the array AB as follows:\n* if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;\n* if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=min(n,j+kd).\n*\n* LDAB (input) INTEGER\n* The leading dimension of the array A. LDAB >= KD+1.\n*\n* S (output) DOUBLE PRECISION array, dimension (N)\n* If INFO = 0, S contains the scale factors for A.\n*\n* SCOND (output) DOUBLE PRECISION\n* If INFO = 0, S contains the ratio of the smallest S(i) to\n* the largest S(i). If SCOND >= 0.1 and AMAX is neither too\n* large nor too small, it is not worth scaling by S.\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, the i-th diagonal element is nonpositive.\n*\n\n* =====================================================================\n*\n\n");
return Qnil;
}
if (rb_hash_aref(rblapack_options, sUsage) == Qtrue) {
printf("%s\n", "USAGE:\n s, scond, amax, info = NumRu::Lapack.zpbequ( uplo, kd, 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_uplo = argv[0];
rblapack_kd = argv[1];
rblapack_ab = argv[2];
if (argc == 3) {
} else if (rblapack_options != Qnil) {
} else {
}
uplo = StringValueCStr(rblapack_uplo)[0];
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_DCOMPLEX)
rblapack_ab = na_change_type(rblapack_ab, NA_DCOMPLEX);
ab = NA_PTR_TYPE(rblapack_ab, doublecomplex*);
kd = NUM2INT(rblapack_kd);
{
na_shape_t shape[1];
shape[0] = n;
rblapack_s = na_make_object(NA_DFLOAT, 1, shape, cNArray);
}
s = NA_PTR_TYPE(rblapack_s, doublereal*);
zpbequ_(&uplo, &n, &kd, ab, &ldab, s, &scond, &amax, &info);
rblapack_scond = rb_float_new((double)scond);
rblapack_amax = rb_float_new((double)amax);
rblapack_info = INT2NUM(info);
return rb_ary_new3(4, rblapack_s, rblapack_scond, rblapack_amax, rblapack_info);
}
void
init_lapack_zpbequ(VALUE mLapack, VALUE sH, VALUE sU, VALUE zero){
sHelp = sH;
sUsage = sU;
rblapack_ZERO = zero;
rb_define_module_function(mLapack, "zpbequ", rblapack_zpbequ, -1);
}
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