LabelsReshuffler.cxx

//
// Created by Filippo Valle on 2019-05-22.
//

#include "LabelsReshuffler.h"

void LabelsReshuffler::Shuffle(){
    fstream inputFile("files.dat", ios::in);

    if(!inputFile.is_open()){
        cerr<<"error opening files.dat"<<endl;
        return;
    }

    string line;
    getline(inputFile, line).good();//header
    auto header = tokenize(line);

    auto nClasses=header.size()-1;
    if(nClasses<1){
        cerr<<"not enough classes"<<endl;
        return;
    }else{
        cout<<"Reading "<<nClasses<<" classes"<<endl;
        BOOST_FOREACH(auto var , header) cout<<var<<"\t";
        cout<<endl;
    }

    vector<vector<string>> allFiles;
    allFiles.reserve(nClasses+1);
    for(int i=0; i<=nClasses;i++) allFiles.emplace_back(vector<string>());

    while (getline(inputFile, line).good()) {
        auto tokenizedLine = tokenize(line);
        int column = 0;
        BOOST_FOREACH(auto var, tokenizedLine) allFiles[column++].push_back(var);
    }

    inputFile.close();

    cout<<"shuffling.."<<endl;
    auto rng = RandomGen::Instance();
    static boost::random::uniform_int_distribution<uint64_t> distribution(0, allFiles[0].size()-1);
    for(uint8_t c=1; c<=nClasses; c++){
        cout<<"shuffling "<<header[c]<<endl;
        shuffleVector(allFiles[c], rng, distribution);
    }


    cout<<"saving output.."<<endl;
    fstream outputFile("files_shuffles.dat",ios::out);
    for(uint8_t c = 1; c<=nClasses;c++){
        outputFile<<","<<header[c];
    }
    outputFile<<endl;

    for(uint64_t iData=0; iData<allFiles[0].size();iData++){
        outputFile<<allFiles[0][iData];
        for(uint8_t c = 1; c<=nClasses;c++){
            outputFile<<","<<allFiles[c][iData];
        }
        outputFile<<endl;
    }

    outputFile.close();
    RandomGen::Destroy();
}

void LabelsReshuffler::shuffleVector(std::vector<string> &vec, RandomGen &rng,
                                     boost::random::uniform_int_distribution<uint64_t> &distr, int nstat) {
    for(int stat=0; stat<nstat;stat++)
        for(uint64_t i =0; i< vec.size();i++)
            iter_swap(vec.begin()+i, vec.begin()+distr(rng));
}

std::vector<std::string> LabelsReshuffler::tokenize(const string& line){
    // escape char is \ , fields are seperated by , , some fields may be quoted with
    boost::escaped_list_separator<char> sep( '\\', ',', '\0' ) ;
    boost::tokenizer< boost::escaped_list_separator<char> > tokenizer( line, sep ) ;
    return std::vector<std::string>(tokenizer.begin(), tokenizer.end()) ;
}