kopia lustrzana https://github.com/Dsplib/libdspl-2.0
168 wiersze
5.3 KiB
C
168 wiersze
5.3 KiB
C
/*
|
||
* Copyright (c) 2015-2020 Sergey Bakhurin
|
||
* Digital Signal Processing Library [http://dsplib.org]
|
||
*
|
||
* This file is part of libdspl-2.0.
|
||
*
|
||
* is free software: you can redistribute it and/or modify
|
||
* it under the terms of the GNU Lesser General Public License as published by
|
||
* the Free Software Foundation, either version 3 of the License, or
|
||
* (at your option) any later version.
|
||
*
|
||
* DSPL 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 Lesser General Public License
|
||
* along with Foobar. If not, see <http://www.gnu.org/licenses/>.
|
||
*/
|
||
|
||
|
||
#include <stdio.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include "dspl.h"
|
||
|
||
|
||
#ifdef DOXYGEN_ENGLISH
|
||
/*! ****************************************************************************
|
||
\ingroup ARRAY_GROUP
|
||
\fn int decimate_cmplx(complex_t* x, int n, int d, complex_t* y, int* cnt)
|
||
\brief
|
||
Complex vector decimation
|
||
|
||
Function `d` times decimates a complex vector `x`. \n
|
||
Output vector `y` keeps values corresponds to:
|
||
`y(k) = x(k*d), k = 0...n/d-1` \n
|
||
|
||
\param[in] x
|
||
Pointer to the input complex vector `x`. \n
|
||
Vector `x` size is `[n x 1]`. \n \n
|
||
|
||
\param[in] n
|
||
Size of input vector `x`. \n \n
|
||
|
||
\param[in] d
|
||
Decimation coefficient. \n
|
||
Each d-th vector will be copy from vector `x` to the
|
||
output vector `y`. \n \n
|
||
|
||
\param[out] y
|
||
Pointer to the output decimated vector `y`. \n
|
||
Output vector size is `[n/d x 1]` will be copy
|
||
to the address `cnt`. \n
|
||
Memory must be allocated. \n \n
|
||
|
||
\param[out] cnt
|
||
Address which will keep decimated vector `y` size. \n
|
||
Pointer can be `NULL`, vector `y` will not return
|
||
in this case. \n \n
|
||
|
||
\return
|
||
`RES_OK` if function calculated successfully. \n
|
||
Else \ref ERROR_CODE_GROUP "code error".
|
||
|
||
Two-times complex vector decimation example:
|
||
|
||
\code{.cpp}
|
||
compex_t x[10] = {{0.0, 0.0}, {1.0, 1.0}, {2.0, 2.0}, {3.0, 3.0}, {4.0, 4.0},
|
||
{5.0, 5.0}, {6.0, 6.0}, {7.0, 7.0}, {8.0, 8.0}, {9.0, 9.0}};
|
||
compex_t y[5];
|
||
int d = 2;
|
||
int cnt;
|
||
|
||
decimate_cmplx(x, 10, d, y, &cnt);
|
||
\endcode
|
||
|
||
As result variable `cnt` will be written value 5 and
|
||
vector `y` will keep array:
|
||
|
||
\verbatim
|
||
c = [0.0+0.0j, 2.0+2.0j, 4.0+4.0j, 6.0+6.0j, 8.0+8.0j]
|
||
\endverbatim
|
||
|
||
\author Sergey Bakhurin www.dsplib.org
|
||
***************************************************************************** */
|
||
#endif
|
||
#ifdef DOXYGEN_RUSSIAN
|
||
/*! ****************************************************************************
|
||
\ingroup ARRAY_GROUP
|
||
\fn int decimate_cmplx(complex_t* x, int n, int d, complex_t* y, int* cnt)
|
||
\brief Децимация комплексного вектора данных
|
||
|
||
Функция производит децимацию комплексного вектора `x` в `d` раз. \n
|
||
В результате выходной вектор `y` содержит значения:
|
||
`y(k) = x(k*d), k = 0...n/d-1` \n
|
||
|
||
\param[in] x
|
||
Указатель на вектор входных данных `x`. \n
|
||
Размер вектора `[n x 1]`. \n \n
|
||
|
||
\param[in] n
|
||
Размер входного вектора `x`. \n \n
|
||
|
||
\param[in] d
|
||
Коэффициент децимации. \n
|
||
В результате децимации из вектора `x` будет взять каждый d-й элемент. \n \n
|
||
|
||
\param[out] y
|
||
Указатель на децимированный вектор `y`. \n
|
||
Размер выходного вектора равен `[n/d x 1]` будет сохранен по адресу `cnt`. \n
|
||
Память должна быть выделена. \n \n
|
||
|
||
\param[out] cnt
|
||
Указатель переменную, в которую будет сохранен
|
||
размер выходного вектора после децимации. \n
|
||
Указатель может быть `NULL`, в этом случае
|
||
размер вектора `y` не возвращается. \n \n
|
||
|
||
\return
|
||
`RES_OK` если функция выполнена успешно. \n
|
||
В противном случае \ref ERROR_CODE_GROUP "код ошибки".
|
||
|
||
Пример децимации комплексного массива данных в 2 раза:
|
||
\code{.cpp}
|
||
compex_t x[10] = {{0.0, 0.0}, {1.0, 1.0}, {2.0, 2.0}, {3.0, 3.0}, {4.0, 4.0},
|
||
{5.0, 5.0}, {6.0, 6.0}, {7.0, 7.0}, {8.0, 8.0}, {9.0, 9.0}};
|
||
compex_t y[5];
|
||
int d = 2;
|
||
int cnt;
|
||
decimate_cmplx(x, 10, d, y, &cnt);
|
||
\endcode
|
||
В результате в переменную `cnt` будет записан размер 5, а вектор `y` будет
|
||
хранить массив данных:
|
||
\verbatim
|
||
c = [0.0+0.0j, 2.0+2.0j, 4.0+4.0j, 6.0+6.0j, 8.0+8.0j]
|
||
\endverbatim
|
||
|
||
\author
|
||
Бахурин Сергей
|
||
www.dsplib.org
|
||
***************************************************************************** */
|
||
#endif
|
||
int DSPL_API decimate_cmplx(complex_t* x, int n, int d, complex_t* y, int* cnt)
|
||
{
|
||
int k = 0, i = 0;
|
||
if(!x || !y)
|
||
return ERROR_PTR;
|
||
if(n < 1)
|
||
return ERROR_SIZE;
|
||
if(d < 1)
|
||
return ERROR_NEGATIVE;
|
||
|
||
k = i = 0;
|
||
while(k + d < n)
|
||
{
|
||
RE(y[i]) = RE(x[k]);
|
||
IM(y[i]) = IM(x[k]);
|
||
k+=d;
|
||
i++;
|
||
}
|
||
if(cnt)
|
||
*cnt = i;
|
||
|
||
return RES_OK;
|
||
}
|
||
|