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
|
#include "rb_lapack.h"
extern VOID claesy_(complex* a, complex* b, complex* c, complex* rt1, complex* rt2, complex* evscal, complex* cs1, complex* sn1);
static VALUE
rblapack_claesy(int argc, VALUE *argv, VALUE self){
VALUE rblapack_a;
complex a;
VALUE rblapack_b;
complex b;
VALUE rblapack_c;
complex c;
VALUE rblapack_rt1;
complex rt1;
VALUE rblapack_rt2;
complex rt2;
VALUE rblapack_evscal;
complex evscal;
VALUE rblapack_cs1;
complex cs1;
VALUE rblapack_sn1;
complex sn1;
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 rt1, rt2, evscal, cs1, sn1 = NumRu::Lapack.claesy( a, b, c, [:usage => usage, :help => help])\n\n\nFORTRAN MANUAL\n SUBROUTINE CLAESY( A, B, C, RT1, RT2, EVSCAL, CS1, SN1 )\n\n* Purpose\n* =======\n*\n* CLAESY computes the eigendecomposition of a 2-by-2 symmetric matrix\n* ( ( A, B );( B, C ) )\n* provided the norm of the matrix of eigenvectors is larger than\n* some threshold value.\n*\n* RT1 is the eigenvalue of larger absolute value, and RT2 of\n* smaller absolute value. If the eigenvectors are computed, then\n* on return ( CS1, SN1 ) is the unit eigenvector for RT1, hence\n*\n* [ CS1 SN1 ] . [ A B ] . [ CS1 -SN1 ] = [ RT1 0 ]\n* [ -SN1 CS1 ] [ B C ] [ SN1 CS1 ] [ 0 RT2 ]\n*\n\n* Arguments\n* =========\n*\n* A (input) COMPLEX\n* The ( 1, 1 ) element of input matrix.\n*\n* B (input) COMPLEX\n* The ( 1, 2 ) element of input matrix. The ( 2, 1 ) element\n* is also given by B, since the 2-by-2 matrix is symmetric.\n*\n* C (input) COMPLEX\n* The ( 2, 2 ) element of input matrix.\n*\n* RT1 (output) COMPLEX\n* The eigenvalue of larger modulus.\n*\n* RT2 (output) COMPLEX\n* The eigenvalue of smaller modulus.\n*\n* EVSCAL (output) COMPLEX\n* The complex value by which the eigenvector matrix was scaled\n* to make it orthonormal. If EVSCAL is zero, the eigenvectors\n* were not computed. This means one of two things: the 2-by-2\n* matrix could not be diagonalized, or the norm of the matrix\n* of eigenvectors before scaling was larger than the threshold\n* value THRESH (set below).\n*\n* CS1 (output) COMPLEX\n* SN1 (output) COMPLEX\n* If EVSCAL .NE. 0, ( CS1, SN1 ) is the unit right eigenvector\n* for RT1.\n*\n\n* =====================================================================\n*\n\n");
return Qnil;
}
if (rb_hash_aref(rblapack_options, sUsage) == Qtrue) {
printf("%s\n", "USAGE:\n rt1, rt2, evscal, cs1, sn1 = NumRu::Lapack.claesy( a, b, c, [: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_a = argv[0];
rblapack_b = argv[1];
rblapack_c = argv[2];
if (argc == 3) {
} else if (rblapack_options != Qnil) {
} else {
}
a.r = (real)NUM2DBL(rb_funcall(rblapack_a, rb_intern("real"), 0));
a.i = (real)NUM2DBL(rb_funcall(rblapack_a, rb_intern("imag"), 0));
c.r = (real)NUM2DBL(rb_funcall(rblapack_c, rb_intern("real"), 0));
c.i = (real)NUM2DBL(rb_funcall(rblapack_c, rb_intern("imag"), 0));
b.r = (real)NUM2DBL(rb_funcall(rblapack_b, rb_intern("real"), 0));
b.i = (real)NUM2DBL(rb_funcall(rblapack_b, rb_intern("imag"), 0));
claesy_(&a, &b, &c, &rt1, &rt2, &evscal, &cs1, &sn1);
rblapack_rt1 = rb_funcall(rb_gv_get("Complex"), rb_intern("new"), 2, rb_float_new((double)(rt1.r)), rb_float_new((double)(rt1.i)));
rblapack_rt2 = rb_funcall(rb_gv_get("Complex"), rb_intern("new"), 2, rb_float_new((double)(rt2.r)), rb_float_new((double)(rt2.i)));
rblapack_evscal = rb_funcall(rb_gv_get("Complex"), rb_intern("new"), 2, rb_float_new((double)(evscal.r)), rb_float_new((double)(evscal.i)));
rblapack_cs1 = rb_funcall(rb_gv_get("Complex"), rb_intern("new"), 2, rb_float_new((double)(cs1.r)), rb_float_new((double)(cs1.i)));
rblapack_sn1 = rb_funcall(rb_gv_get("Complex"), rb_intern("new"), 2, rb_float_new((double)(sn1.r)), rb_float_new((double)(sn1.i)));
return rb_ary_new3(5, rblapack_rt1, rblapack_rt2, rblapack_evscal, rblapack_cs1, rblapack_sn1);
}
void
init_lapack_claesy(VALUE mLapack, VALUE sH, VALUE sU, VALUE zero){
sHelp = sH;
sUsage = sU;
rblapack_ZERO = zero;
rb_define_module_function(mLapack, "claesy", rblapack_claesy, -1);
}
|
