return C++ vector of objects in csv file

[Mar1990]

Hello,

I need your help for return C++ vector of objects in csv file, I have the function below and I need also in the same function to retreive the liste of patinets in csv file with comma as separator of elements :

vector <Patient> LocalService::createListPatients
(int numOfInitialPatient,int numOfCurrentPatient, 
int numOfPatients, int tBetweenCArrival,double min1, 
double max1, double min, double max )
{
    
    vector <Patient> listPatients;
    for(int i = 0; i < numOfPatients; i++) {
        Patient patientI;
        patientI.setId(i+1);
        double latitude = min1 + ((max1 - min1) * (rand () / (double) RAND_MAX));
        double longitude = min + ((max - min) * (rand () / (double) RAND_MAX));
        patientI.setLatitude(latitude);
        patientI.setLongitude(longitude);
        if(i < numOfInitialPatient){
            patientI.setRequestTime(0);
        }else{
patientI.setRequestTime(floor((i -numOfInitialPatient)/numOfCurrentPatient)*tBetweenCArrival);
        }
        listPatients.push_back(patientI);
    }
    return listPatients;
}

Thank you .

[JLBorges]

Required:
a. the definition of the class Patient
b. a few sample lines from the csv file.

[Mar1990]

Hello,

Here is class Patient

#ifndef PATIENT_H
#define PATIENT_H
#include <cstdlib>
#include <iostream>
#include <cmath>
#include <cstdio>
#include <vector>
#include <string>
#include <sstream>
using namespace std;

class Patient
{
    public:
/* ----- constructor to set default values to Patient ------*/
        Patient();

        Patient(int id, int requestTime, int appointTime,	int waitingTime, double latitude, double longitude);

/*------- Getters functions ----------*/
        int getId();
        int getRequestTime();
        int getAppointTime();
        int getWaitingTime();
        double getLatitude();
        double getLongitude();
       

/*------- Setters functions ----------*/
        void setId(int v_id);
        void setRequestTime(int v_time);
        void setAppointTime(int v_time);
        void setWaitingTime(int v_time);
        void setLatitude(double v_latitude);
        void setLongitude(double v_latitude);


/*-------- Function to increment waitingTime -----*/
        virtual ~Patient();

    protected:

    private:
         int id;
         int requestTime;
         int appointTime;
         int waitingTime;
         double latitude;
         double longitude;

};

#endif // PATIENT_H 

for the csv file I need to write on csv file elements of list of patient returned in the function
createListPatients

[JLBorges]

Something along these lines, perhaps:

#include <iostream>
#include <string>
#include <map>
#include <regex>
#include <vector>
#include <sstream>

class patient
{
    public:

        explicit patient( int id = 0, int requestTime = 0, int appointTime = 0,	int waitingTime = 0,
                          double latitude = 0, double longitude = 0 )
                          : id(id), requestTime(requestTime), appointTime(appointTime),
                            waitingTime(waitingTime), latitude(latitude), longitude(longitude) {}

        std::string to_csv() const
        {
            using std::to_string ;
            return "id=" + to_string(id) + ", requestTime=" + to_string(requestTime) +
                   ", appointTime=" + to_string(appointTime) + ", waitingTime=" + to_string(waitingTime) +
                   ", latitude=" + to_string(latitude) + ", longitude=" + to_string(longitude) ;
        }

        explicit patient( std::string csv ) : patient()
        {
            // regular expression to match name = value
            static const std::regex re( "(\\w+)\\s*=\\s*(\\S+)\\s*(?:$|,)" ) ;
            static const std::sregex_iterator end ;

            for( std::sregex_iterator iter( csv.begin(), csv.end(), re ) ; iter != end ; ++iter )
            {
                const auto& match = *iter ;

                // convert values from string to numbers : may throw
                if( match[1] == "id" ) id = std::stoi( match[2] ) ;
                else if( match[1] == "requestTime" ) requestTime = std::stoi( match[2] ) ;
                else if( match[1] == "appointTime" ) appointTime = std::stoi( match[2] ) ;
                else if( match[1] == "waitingTime" ) waitingTime = std::stoi( match[2] ) ;
                else if( match[1] == "latitude" ) latitude = std::stod( match[2] ) ;
                else if( match[1] == "longitude" ) longitude = std::stoi( match[2] ) ;
            }
        }

    private:

        int id;
        int requestTime;
        int appointTime;
        int waitingTime;
        double latitude;
        double longitude;
};

std::vector<patient> get_patients( std::istream& csv_stream ) 
{
    std::vector<patient> result ;

    try
    {
        std::string csv ;
        while( std::getline( csv_stream, csv ) ) result.push_back( patient(csv) ) ;
    }

    catch( const std::bad_alloc& ) { throw ; } // allocation failure: re-throw

    catch( const std::exception& ) // bad input: put the stream into a failed state
    {
        csv_stream.clear( csv_stream.failbit ) ;
    }

    return result ;
}

std::ostream& put_patients( const std::vector<patient>& patients, std::ostream& csv_stream )
{
    for( const patient& p : patients ) csv_stream << p.to_csv() << '\n' ;
    return csv_stream ;
}


int main() // minimal test driver
{
    std::istringstream csv_file
    (
        "id=1,requestTime = 2, appointTime = 3, waitingTime = 4, latitude=5.6, longitude=7.8\n"
        "requestTime = 12, waitingTime = 14, id=11,latitude=15.6, longitude=17.8,appointTime = 13 \n"
        "id=21, longitude=27.8,requestTime = 22, waitingTime = 24,,latitude=25.6 \n"
        "requestTime = 32, id=31\n"
    );

    const auto patients = get_patients(csv_file) ;
    put_patients( patients, std::cout ) ;
}

http://rextester.com/VLOYF80895