Delete Nan points in 3D point cloud TXT file

In the point cloud txt In file , There will be a lot of nan spot , As shown in the figure below ：

To delete nan spot , Use vs Delete the console program

#include "stdafx.h"
#include <fstream> 
#include <iostream>
#include <string>
using namespace std;

int main()
{
    
	fstream in("E:\\3d\\hancon3d\\taotong.txt", ios::in);// Original point cloud file 
	fstream out("E:\\3d\\hancon3d\\taotong4.txt", ios::out);// After processing the file 
	string   str, estr;
	str = "nan nan nan";
	while (getline(in, estr))// obtain   The original point cloud .txt One line 
	{
    
		if (!estr.compare(str))// Compare   The original point cloud .txt Whether the content of each line is consistent with that to be deleted , Just skip the same thing 
			continue;
		out << estr << "\n";// The inconsistent content is written in   After processing the file .txt in , Pay attention to the new line 
	}
	in.close();// Closed flow 
	out.close();
	return 0;
}

In the process of execution , First create a new txt Document for saving none nan Click on the file . After execution , The screenshot of the file is as follows ：