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
|
/* sort/subsetind_source.c
*
* Copyright (C) 1999,2000,2001 Thomas Walter, Brian Gough
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 3, or (at your option) any
* later version.
*
* This source is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
/* find the k-th smallest elements of the vector data, in ascending order */
int
FUNCTION (gsl_sort, smallest_index) (size_t * p, const size_t k,
const BASE * src, const size_t stride,
const size_t n)
{
size_t i, j;
BASE xbound;
if (k > n)
{
GSL_ERROR ("subset length k exceeds vector length n", GSL_EINVAL);
}
if (k == 0 || n == 0)
{
return GSL_SUCCESS;
}
/* take the first element */
j = 1;
xbound = src[0 * stride];
p[0] = 0;
/* examine the remaining elements */
for (i = 1; i < n; i++)
{
size_t i1;
BASE xi = src[i * stride];
if (j < k)
{
j++;
}
else if (xi >= xbound)
{
continue;
}
for (i1 = j - 1; i1 > 0 ; i1--)
{
if (xi > src[p[i1 - 1] * stride])
break;
p[i1] = p[i1 - 1];
}
p[i1] = i;
xbound = src[p[j-1] * stride];
}
return GSL_SUCCESS;
}
int
FUNCTION (gsl_sort_vector,smallest_index) (size_t * p, const size_t k,
const TYPE (gsl_vector) * v)
{
return FUNCTION (gsl_sort, smallest_index) (p, k, v->data, v->stride, v->size);
}
int
FUNCTION (gsl_sort, largest_index) (size_t * p, const size_t k,
const BASE * src, const size_t stride,
const size_t n)
{
size_t i, j;
BASE xbound;
if (k > n)
{
GSL_ERROR ("subset length k exceeds vector length n", GSL_EINVAL);
}
if (k == 0 || n == 0)
{
return GSL_SUCCESS;
}
/* take the first element */
j = 1;
xbound = src[0 * stride];
p[0] = 0;
/* examine the remaining elements */
for (i = 1; i < n; i++)
{
size_t i1;
BASE xi = src[i * stride];
if (j < k)
{
j++;
}
else if (xi <= xbound)
{
continue;
}
for (i1 = j - 1; i1 > 0 ; i1--)
{
if (xi < src[stride * p[i1 - 1]])
break;
p[i1] = p[i1 - 1];
}
p[i1] = i;
xbound = src[stride * p[j-1]];
}
return GSL_SUCCESS;
}
int
FUNCTION (gsl_sort_vector,largest_index) (size_t * p, const size_t k,
const TYPE (gsl_vector) * v)
{
return FUNCTION (gsl_sort, largest_index) (p, k, v->data, v->stride, v->size);
}
|
