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
|
/*****************************************************************************
* *
* Small (Matlab/Octave) Toolbox for Kriging *
* *
* Copyright Notice *
* *
* Copyright (C) 2015 CentraleSupelec *
* Copyright (C) 2011, 2012 SUPELEC *
* *
* Authors: Julien Bect <julien.bect@centralesupelec.fr> *
* Emmanuel Vazquez <emmanuel.vazquez@centralesupelec.fr> *
* *
* Copying Permission Statement *
* *
* This file is part of *
* *
* STK: a Small (Matlab/Octave) Toolbox for Kriging *
* (https://github.com/stk-kriging/stk/) *
* *
* STK 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 of the License, or (at your *
* option) any later version. *
* *
* STK 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. *
* *
* You should have received a copy of the GNU General Public License *
* along with STK. If not, see <http://www.gnu.org/licenses/>. *
* *
****************************************************************************/
#include "stk_mex.h"
static void distance2(double* x, double* y, double* h, size_t nx, size_t ny, size_t dim)
{
size_t i, j, kx, ky;
double diff, lambda;
for (i = 0; i < nx; i++) {
for (j = 0; j < ny; j++) {
/* compute distance between x[i,:] and y[j,:] */
lambda = 0.0;
for (kx = i, ky = j; kx < dim * nx; kx += nx, ky += ny)
{
diff = x[kx] - y[ky];
lambda += diff * diff;
}
/* store the result in h */
h[i+nx*j] = sqrt(lambda);
}
}
}
mxArray* compute_distance_xy(const mxArray* x, const mxArray* y)
{
size_t d, mx, my;
mxArray* h;
if((!stk_is_realmatrix(x)) || (!stk_is_realmatrix(y)))
mexErrMsgTxt("Input arguments should be real-valued double-precision array.");
/* Check that the input arguments have the same number of columns */
if (mxGetN(y) != (d = mxGetN(x)))
mexErrMsgTxt("Both input arguments should have the same number of columns.");
/* Read the size (number of lines) of each input argument */
mx = mxGetM(x);
my = mxGetM(y);
/* Create a matrix for the return argument */
h = mxCreateDoubleMatrix(mx, my, mxREAL);
/* Do the actual computations in a subroutine */
distance2(mxGetPr(x), mxGetPr(y), mxGetPr(h), mx, my, d);
return h;
}
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray*prhs[])
{
if (nlhs > 1) /* Check number of output arguments */
mexErrMsgTxt("Too many output arguments.");
if (nrhs != 2) /* Check number of input arguments */
mexErrMsgTxt("Incorrect number of input arguments.");
plhs[0] = compute_distance_xy(prhs[0], prhs[1]);
}
|
