NFFT  3.3.2alpha
kernels.h
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1 /*
2  * Copyright (c) 2002, 2016 Jens Keiner, Stefan Kunis, Daniel Potts
3  *
4  * This program is free software; you can redistribute it and/or modify it under
5  * the terms of the GNU General Public License as published by the Free Software
6  * Foundation; either version 2 of the License, or (at your option) any later
7  * version.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
11  * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
12  * details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc., 51
16  * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17  */
18 
22 #ifndef KERNELS_H
23 #define KERNELS_H
24 
25 #include "config.h"
26 
27 #ifdef HAVE_COMPLEX_H
28 #include <complex.h>
29 #endif
30 
31 #include "nfft3.h"
32 #include "infft.h"
33 
34 #ifdef __cplusplus
35 extern "C"
36 {
37 #endif /* __cplusplus */
38 
44 C gaussian(R x, int der, const R *param); /* K(x)=exp(-x^2/c^2) */
45 C multiquadric(R x, int der, const R *param); /* K(x)=sqrt(x^2+c^2) */
46 C inverse_multiquadric(R x, int der, const R *param); /* K(x)=1/sqrt(x^2+c^2) */
47 C logarithm(R x, int der, const R *param); /* K(x)=log |x| */
48 C thinplate_spline(R x, int der, const R *param); /* K(x) = x^2 log |x| */
49 C one_over_square(R x, int der, const R *param); /* K(x) = 1/x^2 */
50 C one_over_modulus(R x, int der, const R *param); /* K(x) = 1/|x| */
51 C one_over_x(R x, int der, const R *param); /* K(x) = 1/x */
52 C inverse_multiquadric3(R x, int der, const R *param); /* K(x) = 1/sqrt(x^2+c^2)^3 */
53 C sinc_kernel(R x, int der, const R *param); /* K(x) = sin(cx)/x */
54 C cosc(R x, int der, const R *param); /* K(x) = cos(cx)/x */
55 C kcot(R x, int der, const R *param); /* K(x) = cot(cx) */
56 C one_over_cube(R x, int der, const R *param); /* K(x) = 1/x^3 */
57 /* \} */
58 
59 #ifdef __cplusplus
60 } /* extern "C" */
61 #endif /* __cplusplus */
62 
63 #endif
64 /* kernels.h */
nfft3.h