(ja)
パターンマッチング可能な飛跡ファイル
https://1drv.ms/f/s!Ap9xAxIuzM0xlLxu6slGIjkY3gSjNg
Q1. どういう手段でもいいので、 beam_4372-2_u.txt
の飛跡と beam_4372-2_d.txt
の飛跡の位置ずれを計算しよう。
Q2. 計算方法について、互いに紹介しよう。
Q3. これは、位置ずれのピークを求めるソースコードである。 std::map
はどういう働きをするのか調べよう。
- 全ての飛跡の位置ずれを
bin_width
ごとのヒストグラムに詰め
- また周辺
n_bin_bg x n_bin_bg
でぼかしたヒストグラムを作り
- その差のヒストグラムを求め
- bin内の内容が最大のbinを位置ずれのピークとした。
Q4. 前回配布したファイルはパターンマッチングが成功しない。成功しないと言うためにはどうすればよいか考えよう。
https://1drv.ms/t/s!Ap9xAxIuzM0xlLlaOr2g5qaKpYqF2w
https://1drv.ms/t/s!Ap9xAxIuzM0xlLlbUgqNsGvbe4Eq6w
(en)
Trajectory file for pattern-matching
https://1drv.ms/f/s!Ap9xAxIuzM0xlLxu6slGIjkY3gSjNg
Q1. Calculate the position shift between the trajectory of beam_4372-2_u.txt
and the trajectory ofbeam_4372-2_d.txt
with any way.
Q2. Introduce each other about your calculation methods.
Q3. This is a source code to search peak position shift . Examine what std::map
does.
- Position shift of all trajectories are packed in a histogram for each
bin_width
.
- Create a blurred histogram with surrounding
n_bin_bg x n_bin_bg
.
- Subtract the histogram from the blurred histogram
- Find the peak with the the maximum content
Q4. Pattern matching does not succeed in files distributed last time. Let's see what we should say to show that the pattern matching does not succeed.
https://1drv.ms/t/s!Ap9xAxIuzM0xlLlaOr2g5qaKpYqF2w
https://1drv.ms/t/s!Ap9xAxIuzM0xlLlbUgqNsGvbe4Eq6w
#include <string>
#include <iostream>
#include <vector>
#include <fstream>
#include <sstream>
#include <map>
int main() {
string path1 = "beam_4372-2_u.txt";
string path2 = "beam_4372-2_d.txt";
vector<track> vtrack1, vtrack2;
cout << vtrack1.size() << " -> ";
read_txt(path1, vtrack1);
cout << vtrack1.size() << endl;
cout << vtrack2.size() << " -> ";
read_txt(path2, vtrack2);
cout << vtrack2.size() << endl;
map<string, int> hist;
map<string, int> hist_bg;
double bin_width = 0.002;
int n_bin_bg = 3;
for (int i1 = 0; i1 < vtrack1.size(); i1++) {
for (int i2 = 0; i2 < vtrack2.size(); i2++) {
double dx = vtrack2[i2].px - vtrack1[i1].px;
double dy = vtrack2[i2].py - vtrack1[i1].py;
int dxi = round(dx / bin_width);
int dyi = round(dy / bin_width);
hist[to_string(dxi) + "_" + to_string(dyi)]++;
for (int bgx = -(n_bin_bg - 1) / 2; bgx <= (n_bin_bg - 1) / 2; bgx++) {
for (int bgy = -(n_bin_bg - 1) / 2; bgy <= (n_bin_bg - 1) / 2; bgy++) {
hist_bg[to_string(dxi + bgx) + "_" + to_string(dyi + bgy)]++;
}
}
}
}
int max_value = 0;
string peak_position = "";
for (auto &p : hist) {
p.second -= hist_bg[p.first] / double(n_bin_bg*n_bin_bg);
if (max_value < p.second)
{
peak_position = p.first;
max_value = p.second;
}
}
string buf;
stringstream ss(peak_position);
getline(ss, buf, '_');
int peak_position_x = std::stoi(buf);
getline(ss, buf, '_');
int peak_posision_y = std::stoi(buf);
for (int ix = -3; ix <= 3; ix++) {
for (int iy = -3; iy <= 3; iy++) {
string str = std::to_string(ix + peak_position_x) + "_" + std::to_string(iy + peak_posision_y);
cout << hist[str] << " ";
}
cout << endl;
}
cout << "peak (x, y) = (" << peak_position_x*bin_width << ", " << peak_posision_y*bin_width << ") " << endl;
cout << "peak bin content = " << max_value << endl;
cin.get();
}