matlab filter 函数,C++ 实现matlab filter()函数
时间: 2023-08-23 16:04:38 浏览: 76
Matlab的`filter()`函数是用于对信号进行数字滤波的函数。在C++中,可以使用数字信号处理库(DSP)或C++标准模板库(STL)来实现`filter()`函数的功能。
使用DSP库实现`filter()`函数:
```c++
#include <dsp.h>
// Define input signal and filter coefficients
float inputSignal[] = {0.2, 0.4, 0.6, 0.8, 1.0};
float filterCoeffs[] = {0.5, 0.5};
// Define filter state structure
static fir_state_fr32 filterState;
// Define output signal buffer
float outputSignal[5];
// Define filter length
int filterLength = 2;
// Define input and output buffer lengths
int inputLength = 5;
int outputLength = 5;
// Call filter function
fir_fr32(inputSignal, outputSignal, inputLength, filterCoeffs, &filterState, filterLength);
// Print output signal values
for (int i = 0; i < outputLength; i++)
{
printf("%f\n", outputSignal[i]);
}
```
使用STL库实现`filter()`函数:
```c++
#include <vector>
#include <numeric>
#include <algorithm>
// Define input signal and filter coefficients as vectors
std::vector<float> inputSignal = {0.2, 0.4, 0.6, 0.8, 1.0};
std::vector<float> filterCoeffs = {0.5, 0.5};
// Define output signal buffer
std::vector<float> outputSignal(inputSignal.size());
// Call filter function
std::transform(inputSignal.begin(), inputSignal.end(), outputSignal.begin(),
[&filterCoeffs](float x) {
static std::vector<float> filterState(filterCoeffs.size());
filterState.push_back(x);
filterState.erase(filterState.begin());
return std::inner_product(filterState.begin(), filterState.end(),
filterCoeffs.begin(), 0.0);
});
// Print output signal values
for (auto&& val : outputSignal)
{
printf("%f\n", val);
}
```
这里使用了C++11中的lambda表达式来定义信号处理函数,并使用STL中的`transform()`函数来实现数字滤波的功能。