//////////////////////////////////////////////////////////////////////////
//                                                                      //
// MyVec                                                                //
//                                                                      //
// A TVectorD with extra functions:                                     //                 
//    ReadValues(filename)                                              //
//    WriteValues(filename)                                             //
//    to read and write its values from / to a flat file                //
//                                                                      //
//  To use this interactively: (assume vec.asc contains 6 values):      //
//  .L MyVec.cxx+                                                       //
//   MyVec x(6);                                                        //
//   x.ReadValues("vec.asc")                                            //
//                                                                      //
//////////////////////////////////////////////////////////////////////////

#include "TVectorD.h"
#include "iostream"
#include "fstream"

namespace std {} using namespace std;

class MyVec : public TVectorD {
public:
   MyVec(){};
   MyVec(Int_t n);
   MyVec(Int_t n, Double_t *val);
   ~MyVec() {};
   Int_t ReadValues(const Char_t * fname);
   Int_t WriteValues(const Char_t * fname);
   ClassDef(MyVec,0)   // A TVectorD with ASCII I/O facility
};

ClassImp(MyVec)
//__________________________________________________________

MyVec::MyVec(Int_t n, Double_t *val) : TVectorD (n, val){};
//__________________________________________________________

MyVec::MyVec(Int_t n) : TVectorD (n){};
//___________________________________________________

Int_t MyVec::ReadValues(const Char_t * fname)
{
   // Read values from ascii file with name fname
   // Return number of items read

   Int_t nread = 0;
   ifstream inf(fname);
   if (inf.fail()) {
      cout << "Cant open: " << fname << endl;
   } else {
      for (Int_t i = 0; i < GetNrows(); i++) {
         Float_t temp;
         inf >> temp;
         if (inf.eof())break;
         (*this)[i] = temp;
         nread++;
      }
   }
   if (nread != GetNrows())
      cout << "Warning: Values read: " << nread 
           << " expected: " << GetNrows()<< endl;
   return nread;
}
//__________________________________________________

Int_t MyVec::WriteValues(const Char_t * fname)
{
   // Write values to ascii file with name fname
   // Return number of items written

   Int_t written = 0;
   ofstream inf(fname);
   if (inf.fail()) {
      cout << "Cant open: " << fname << endl;
   } else {
      for (Int_t i = 0; i < GetNrows(); i++) {
         inf << (*this)[i];
         written++;
      }
   }
   return written;
}