Reading certain values of a vector and write them into another vector

[oayrancioglu]

Greetings,

I couldn't succeed on doing that. Here's basic parts of my code that i tried to read certain rows within a vector and tried to write them into another vector..

 int c=0;
    cout << '\n';
    cout << "QLT MLC Values:" << '\n';
	for (int i=0; i<Numbers.size(); i++){
    if (i>=74 && i<=104){
    QLT[c]=Numbers[i];
    cout << "Carriage-B QLT MLC Number " << i-59 << " = " << QLT[c] << '\n'; 
    i=i+1;
    c=c+1;
    }
	}

But when i run this code, i've got "Segmentation Fault" all the time. Why do i get it? I couldn't understand that..

By the way, this loop of logical state skips every first element that comes after reading rows which i want to store. So it reads rows like "74, 76, 78, ... 104".

Any help would be great = /

Thank you.

[helios]

Does QLT.size() == 0 at line 1? Vectors don't grow automatically by writing outside their bounds, you have to grow them explicitly by calling resize(), push_back(), or emplace_back(). You should change lines 6 and 7 to

QLT.push_back(Numbers[i]);
cout << "Carriage-B QLT MLC Number " << i-59 << " = " << QLT.back() << '\n';

By the way, check your editor settings. It's mixing tabs and spaces, which is frowned upon by most people. For example, it makes your formatting unreadable on this site.

[oayrancioglu]

Hello,

Does QLT.size() == 0 at line 1?

Yes.

I tried "Push back" but Values couldn't be written on the screen. After that i just tried what i do in matlab all the time. I thought it could work but it did not.. I didn't know ".back()" part of code. Thank you very much for helping me. Its working now.

Apologize but I dont understand? What do you mean "mixing tabs and spaces" ? I use Code::Blocks as an Editor in Linux. I did look settings but couldn't see anything related to this