我对此有一点认识。
基本上我有一个2D矢量包含大小为1024x1024的块,我计算这些块的总能量。如果块因此在特定阈值内,则它们可以存储在另一个2D矢量内。问题是,我需要捕获(推回)多个块,直到阈值变为负值。这是一个例子:
blocks[0] = 0.124 <- This is not pushed back
blocks[1] = 0.123 <- This is not pushed back
blocks[2] = 0.456 <- This is not pushed back
blocks[3] = 1.23 <- This is pushed back to vector[0]
blocks[4] = 2.45 <- This is pushed back to vector[0]
blocks[5] = 7.23 <- This is pushed back to vector[0]
blocks[6] = 8.12 <- This is pushed back to vector[0]
blocks[7] = 0.12 <- This is not pushed back
blocks[8] = 0.124 <- This is not pushed back
blocks[9] = 0.125 <- This is not pushed back
blocks[10] = 8.123 <- This is pushed back to vector[1]
blocks[11] = 8.123 <- This is pushed back to vector[1]
blocks[12] = 8.123 <- This is pushed back to vector[1]
blocks[13] = 0.12 <- This is not pushed back
所以基本上,当块的阈值为真时,然后将块插入位置[i]的2D矢量中,直到块变为负值。当该值再次变为真时,块被推回到位置[i + 1]
到目前为止我的想法:
如果我有两个变量来存储需要推回的块数,另一个变量存储在向量被推回的位置...... I.e。 currentpos[1]
因此下一个位置为currentpos[2]
您可以提供任何帮助,伪代码会更好。
编辑:
这是阈值函数:
bool threshold (vector<double> val)
{
//short threshold = 10000;
float sum = 0.0;
for(unsigned i=0; (i < val.size()); i++)
{
sum += (val[i]*val[i]);
}
return (sum > 0.082);
}
然后我有以下内容:
std::vector<vector<double> > blocks = splitVector(1024, 1024); // this is fine, it works!
// then
std::vector<vector<double> > clusters;
for(unsigned i=0; (i < blocks.size()); i++)
{
if(threshold(blocks[i])) {
// true
clusters[i].push_back(d[i]);
}else{
// false do not do anything
}
}
但我遇到的问题是,“群集”只会包含已返回的“正”块数量。那么blocks.size() = 745 (size)
哪里clusters.size() = 6
这更有意义呢?
编辑 - 此示例有效:
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
bool energy(const std::vector<double> &vals)
{
float sum = 0.0;
for(unsigned i=0; (i < vals.size()); i++)
{
sum += (vals[i]*vals[i]);
}
//cout << sum << endl;
return (sum >= 5);
}
int main(int argc, char *argv[]) {
std::vector<vector<double> > vals {
{0, 0, 0, 0, 0}, // This has an energy of "0" -> does not count
{1, 1, 1, 1, 1}, // This has an energy of "5" -> push_back to vector[0]
{1, 1, 1, 1, 1}, // This has an energy of "5" -> push_back to vector[0]
{1, 1, 1, 1, 1}, // This has an energy of "5" -> push_back to vector[0]
{1, 1, 1, 1, 1}, //This has an energy of "5" -> push_back to vector[0]
{0, 0, 0, 0, 0}, // This has an energy of "0" -> does not count && start a new vector
{1, 2, 3, 4, 5}, // This has an energy of "55" -> push_back to vector[1]
{1, 2, 3, 4, 5}, // This has an energy of "55" -> push_back to vector[1]
{1, 2, 3, 4, 5}, // This has an energy of "55" -> push_back to vector[1]
{1, 2, 3, 4, 5} // This has an energy of "55" -> push_back to vector[1]
};
std::vector<vector<double> > clusters;
//std::for_each(vals.begin(), vals.end(), energy);
int j = 0;
for(unsigned i=0; (i < vals.size()); i++)
{
if(energy(vals[i]))
{
clusters.resize(j + 1);
clusters[j] = vals[i];
}else if(!energy(vals[i]) && energy(vals[i+1]))
{
j++;
}
}
}
但是,不是“连接”值,而是覆盖它们,因此clusters[0]
只包含{1, 1, 1, 1, 1}
运算符的值{1, 1, 1, 1, 1} + {1, 1, 1, 1, 1} + {1, 1, 1, 1, 1}
而不是+
,我的意思是连接而不是元素的总和。
因此如何连接值?
答案 0 :(得分:1)
您可以使用以下psuedocode:
bool flag = false;
int j = 0;
for i in blocks
{
if(blocks[i] > 0)
{
vector[j].push_back(blocks[i]);
flag = true;
}
else
if(flag)
{
j++;
flag = flase;
}
}
答案 1 :(得分:0)
如果我理解你想要做的正确,我会做一些简单的事情:
bool wasNeg = true;
for(blocks) {
if(isNegative()) {
wasNeg = true;
} else {
if(wasNeg) {
outVec.push_back(vector());
}
outVec.back().push_back(value);
wasNeg = false;
}
}
这总是插入输出向量中的最新向量。只有当两者之间存在负值时,才会通过推送新的向量来分隔块。