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
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
#include "ltfat.h"
#include "ltfat_types.h"
/* This routines changes the center of a vector from the beginning
* to the middle.
*
* f : Real valued input array.
* L : Length of input array
* W : Number of arrays to transform.
* h : Output, same size as input.
*
* For the typical use of a single vector, set W=1.
*
* This function works in the exact same way as the Matlab command
*
* h = fftshift(f,1);
*
*/
LTFAT_EXTERN void
LTFAT_NAME(fftshift_r)(const LTFAT_REAL *f, const ltfatInt L, LTFAT_REAL *h)
{
ltfatInt ii;
const div_t domod=div(L,2);
for (ii=0; ii<domod.quot; ii++)
{
h[ii]=f[ii+domod.quot+domod.rem];
}
for (ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii+domod.quot]=f[ii];
}
}
/* This does the reverse of fftshift. When L is even, this function is
* identical to fftshift, but for odd L there is a difference.
*
* f : Real valued input array.
* L : Length of input array
* W : Number of arrays to transform.
* h : Output, same size as input.
*
* For the typical use of a single vector, set W=1.
*
* This function works in the exact same way as the Matlab command
*
* h = ifftshift(f,1);
*
*/
LTFAT_EXTERN void
LTFAT_NAME(ifftshift_r)(const LTFAT_REAL *f, const ltfatInt L, LTFAT_REAL *h)
{
ltfatInt ii;
div_t domod;
domod=div(L,2);
for (ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii]=f[ii+domod.quot];
}
for (ii=0; ii<domod.quot; ii++)
{
h[ii+domod.quot+domod.rem]=f[ii];
}
}
/* This routine changes an FIR window to a LONG window.
*
* Input parameters:
* f : Real valued input array.
* Lfir : Length of input array
* Llong : Length of output array
* h : Output array
*/
LTFAT_EXTERN void
LTFAT_NAME(fir2long_r)(const LTFAT_REAL *f, const ltfatInt Lfir, const ltfatInt Llong,
LTFAT_REAL *h)
{
const div_t domod=div(Lfir,2);
/* ---- In the odd case, the additional element is kept in the first half. ---*/
for (ltfatInt ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii]=f[ii];
}
for (ltfatInt ii=domod.quot+domod.rem; ii<Llong-domod.quot; ii++)
{
h[ii]=0.0;
}
const ltfatInt ss=Llong-Lfir;
for (ltfatInt ii=domod.quot+domod.rem; ii<Lfir; ii++)
{
h[ii+ss]=f[ii];
}
}
/* This routine changes an FIR window to a LONG window.
*
* Input parameters:
* f : Complex valued input array.
* Lfir : Length of input array
* Llong : Length of output array
* h : Output array
*/
LTFAT_EXTERN void
LTFAT_NAME(fir2long_c)(const LTFAT_COMPLEX *f, const ltfatInt Lfir, const ltfatInt Llong,
LTFAT_COMPLEX *h)
{
const div_t domod=div(Lfir,2);
/* ---- In the odd case, the additional element is kept in the first half. ---*/
for (ltfatInt ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii]=f[ii];
}
for (ltfatInt ii=domod.quot+domod.rem; ii<Llong-domod.quot; ii++)
{
h[ii] = (LTFAT_COMPLEX) 0.0;
}
const ltfatInt ss=Llong-Lfir;
for (ltfatInt ii=domod.quot+domod.rem; ii<Lfir; ii++)
{
h[ii+ss]=f[ii];
}
}
/* This routine changes a LONG window to an FIR window.
*
* Input parameters:
* f : Real valued input array.
* Llong : Length of input array
* Lfir : Length of output array
* h : Output array
*/
LTFAT_EXTERN void
LTFAT_NAME(long2fir_r)(const LTFAT_REAL *f, const ltfatInt Llong, const ltfatInt Lfir, LTFAT_REAL *h)
{
const div_t domod=div(Lfir,2);
/* ---- In the odd case, the additional element is kept in the first half. ---*/
for (ltfatInt ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii]=f[ii];
}
const ltfatInt ss=Llong-Lfir;
for (ltfatInt ii=domod.quot+domod.rem; ii<Lfir; ii++)
{
h[ii]=f[ii+ss];
}
}
LTFAT_EXTERN void
LTFAT_NAME(long2fir_c)(const LTFAT_COMPLEX *f, const ltfatInt Llong, const ltfatInt Lfir, LTFAT_COMPLEX *h)
{
const div_t domod=div(Lfir,2);
/* ---- In the odd case, the additional element is kept in the first half. ---*/
for (ltfatInt ii=0; ii<domod.quot+domod.rem; ii++)
{
h[ii]=f[ii];
}
const ltfatInt ss=Llong-Lfir;
for (ltfatInt ii=domod.quot+domod.rem; ii<Lfir; ii++)
{
h[ii]=f[ii+ss];
}
}
|
