C++ 跨窗

假设我有一个向量：

x = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14]

我需要做的是将此向量拆分为块大小为

blocksize

的块，并重叠

blocksize=4

overlap=2

结果将是一个二维向量，其大小
4
包含
6
值

x[0]=[1,3,5,7,9,11]

x[1]=[2 4 6 8 10 12]

…

我已尝试通过以下功能实现此功能：

std::vector<std::vector<double> > stride_windows(std::vector<double> &data, std::size_t 
NFFT, std::size_t overlap)
{
    std::vector<std::vector<double> > blocks(NFFT); 

    for(unsigned i=0; (i < data.size()); i++)
    {
        blocks[i].resize(NFFT+overlap);
        for(unsigned j=0; (j < blocks[i].size()); j++)
        {
            std::cout << data[i*overlap+j] << std::endl;
        }
    }
}

因此，基本上已经创建了4个块，每个块都包含一个值，其中元素被
重叠部分跳过

编辑2：

这是我需要到达的地方：

overlap
的值将与
x
的结果在向量内的位置重叠：

block1 = [1, 3, 5, 7, 9, 11] 

请注意实际矢量块：

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14

Value: 1 -> This is pushed into block "1"

Value 2 -> This is not pushed into block "1" (overlap is skip 2 places in the vector)

Value 3 -> This is pushed into block "1" 

value 4 -> This is not pushed into block "1" (overlap is skip to places in the vector)

value 5 -> This is pushed into block "1"

value 6 -> "This is not pushed into block "1" (overlap is skip 2 places in the vector)

value 7 -> "This value is pushed into block "1"

value 8 -> "This is not pushed into block "1" (overlap is skip 2 places in the vector)"

value 9 -> "This value is pushed into block "1"

value 10 -> This value is not pushed into block "1" (overlap is skip 2 places in the 
                                                     vector)

value 11 -> This value is pushed into block "1"

第2区

Overlap = 2; 

value 2 - > Pushed back into block "2" 
value 4 -> Pushed back into  block "2"
value 6, 8, 10 etc.. 

因此，每次向量中的位置都会被“重叠”跳过。在这种情况下，它的值为2

这就是预期的输出：

[[ 1  3  5  7  9 11]
 [ 2  4  6  8 10 12]
 [ 3  5  7  9 11 13]
 [ 4  6  8 10 12 14]]

如果我没弄错的话，你已经很接近了。你需要像下面这样的东西。我使用了
int
，因为坦率地说，它比
double
=P更容易打字

#include <iostream>
#include <algorithm>
#include <vector>
#include <limits>
#include <iterator>

std::vector<std::vector<int>>
split(const std::vector<int>& data, size_t blocksize, size_t overlap)
{
    // compute maximum block size
    std::vector<std::vector<int>> res;
    size_t minlen = (data.size() - blocksize)/overlap + 1;
    auto start = data.begin();
    for (size_t i=0; i<blocksize; ++i)
    {
        res.emplace_back(std::vector<int>());
        std::vector<int>& block = res.back();

        auto it = start++;
        for (size_t j=0; j<minlen; ++j)
        {
            block.push_back(*it);
            std::advance(it,overlap);
        }
    }
    return res;
}

int main()
{
    std::vector<int> data { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 };

    for (size_t i=2; i<6; ++i)
    {
        for (size_t j=2; j<6; ++j)
        {
            std::vector<std::vector<int>> blocks = split(data, i, j);

            std::cout << "Blocksize = " << i << ", Overlap = " << j << std::endl;
            for (auto const& obj : blocks)
            {
                std::copy(obj.begin(), obj.end(), std::ostream_iterator<int>(std::cout, " "));
                std::cout << std::endl;
            }
            std::cout << std::endl;
        }
    }
    return 0;
}

我不明白您的示例预期输出与您的问题描述如何匹配。“你能完整地写下来吗？”纳布拉谢谢你的回答。我已经更新了问题=），所以你的代码做了正确的事情，只交换行和列？@Nabla-是的，我相信是这样。它不是跳转到
overlap
元素，而是在
overlap
元素上拆分如果有意义的话..先生，你是个向导：D非常感谢！！
[[ 1  3  5  7  9 11]
 [ 2  4  6  8 10 12]
 [ 3  5  7  9 11 13]
 [ 4  6  8 10 12 14]]

#include <iostream>
#include <algorithm>
#include <vector>
#include <limits>
#include <iterator>

std::vector<std::vector<int>>
split(const std::vector<int>& data, size_t blocksize, size_t overlap)
{
    // compute maximum block size
    std::vector<std::vector<int>> res;
    size_t minlen = (data.size() - blocksize)/overlap + 1;
    auto start = data.begin();
    for (size_t i=0; i<blocksize; ++i)
    {
        res.emplace_back(std::vector<int>());
        std::vector<int>& block = res.back();

        auto it = start++;
        for (size_t j=0; j<minlen; ++j)
        {
            block.push_back(*it);
            std::advance(it,overlap);
        }
    }
    return res;
}

int main()
{
    std::vector<int> data { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 };

    for (size_t i=2; i<6; ++i)
    {
        for (size_t j=2; j<6; ++j)
        {
            std::vector<std::vector<int>> blocks = split(data, i, j);

            std::cout << "Blocksize = " << i << ", Overlap = " << j << std::endl;
            for (auto const& obj : blocks)
            {
                std::copy(obj.begin(), obj.end(), std::ostream_iterator<int>(std::cout, " "));
                std::cout << std::endl;
            }
            std::cout << std::endl;
        }
    }
    return 0;
}

Blocksize = 2, Overlap = 2
1 3 5 7 9 11 13 
2 4 6 8 10 12 14 

Blocksize = 2, Overlap = 3
1 4 7 10 13 
2 5 8 11 14 

Blocksize = 2, Overlap = 4
1 5 9 13 
2 6 10 14 

Blocksize = 2, Overlap = 5
1 6 11 
2 7 12 

Blocksize = 3, Overlap = 2
1 3 5 7 9 11 
2 4 6 8 10 12 
3 5 7 9 11 13 

Blocksize = 3, Overlap = 3
1 4 7 10 
2 5 8 11 
3 6 9 12 

Blocksize = 3, Overlap = 4
1 5 9 
2 6 10 
3 7 11 

Blocksize = 3, Overlap = 5
1 6 11 
2 7 12 
3 8 13 

Blocksize = 4, Overlap = 2
1 3 5 7 9 11 
2 4 6 8 10 12 
3 5 7 9 11 13 
4 6 8 10 12 14 

Blocksize = 4, Overlap = 3
1 4 7 10 
2 5 8 11 
3 6 9 12 
4 7 10 13 

Blocksize = 4, Overlap = 4
1 5 9 
2 6 10 
3 7 11 
4 8 12 

Blocksize = 4, Overlap = 5
1 6 11 
2 7 12 
3 8 13 
4 9 14 

Blocksize = 5, Overlap = 2
1 3 5 7 9 
2 4 6 8 10 
3 5 7 9 11 
4 6 8 10 12 
5 7 9 11 13 

Blocksize = 5, Overlap = 3
1 4 7 10 
2 5 8 11 
3 6 9 12 
4 7 10 13 
5 8 11 14 

Blocksize = 5, Overlap = 4
1 5 9 
2 6 10 
3 7 11 
4 8 12 
5 9 13 

Blocksize = 5, Overlap = 5
1 6 
2 7 
3 8 
4 9 
5 10