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Cling interface function


Hi everyone!

I just finished writing my first actual script, but when I’m trying to run it in ROOT with " .x read_to_vectors.C " I get this message:

IncrementalExecutor::executeFunction: symbol ‘_Z15read_to_vectorsv’ unresolved while linking [cling interface function]!
You are probably missing the definition of read_to_vectors()
Maybe you need to load the corresponding shared library?

Ubuntu: 18.04
gcc : 7.3.0

Since this is my very first script I don’t really know if I made a terrible mistake or if it’s my system’s fault. Could someone please give me a hint ?

P.S. this forum has been a great help ! Thank you all very much!!

#include <fstream>
#include <iostream>
#include <string>
#include <sstream>
#include <vector>
#include "TGraph.h"
#include "TFile.h"
using namespace std;
void read_to_vectors();
int main()
  vector<float> vecCounts, vecTime, veccps;
  float  counts, time;
  Int_t dim =32;
  ifstream inputFile("data12.txt");
    while (inputFile >> time >>counts)

  for (int i(0); i< vecCounts.size(); i++)

  cout << vecTime[i] << " " <<veccps[i] << endl;
  TFile *file = new TFile("Graph1.root","RECREATE");
  TGraph *gr1 = new TGraph (dim , &vecCounts[0], &vecTime[0]);
  return 0;



Hi Ilias,

the problem is that the function read_to_vectors has no implementation and cling is erroring out because of that.



I replaced the “int main()” line with “int read_to_vectors()” and it worked.

Thanks a lot!!