Re: Single call of procedure works while recurring call in loop returns error.

Could you provide a complete script and the data file to execute it?

Rene

Stephan Zimmer wrote:
> Hi ROOTers,
> I wonder if someone of you might understand why the following code
> crashes...
>
> double CotTheta(const double x_i, const double alpha[2]){
> // returns the estimate y(x_i) based on the theoretical distribution
> return alpha[0]*x_i - alpha[1]*pow(x_i,-1);
> }
>
> double CalculateChi2(const vector<double> x, const vector<double> y,
> const vect\
> or<double> yError, const double alpha[2]){
> // returns the chi2 value for a given set of parameters
> double sumchi2=0;
> for (unsigned int i = 0; i<x.size(); i++){
> sumchi2=sumchi2+(pow(yError[i],-2)*pow(y[i]-CotTheta(x[i],alpha),2));
> }
> return sumchi2;
> }
>
> void littleHenry(){
>
> TVirtualFitter::SetDefaultFitter("Minuit");
>
> // readout henry.dat
> vector<double> xVec;
> vector<double> xEVec;
> vector<double> yVec;
> vector<double> yEVec;
> double x(0),y(0),xE(0), yE(0);
> double output[3];
> FILE *data;
> char datafname[]="henry.dat";
>
> data = fopen(datafname,"r");
> while (fscanf(data, "%lf %lf %lf %lf",&x,&xE,&y,&yE) != EOF) {
> xVec.push_back(x);
> yVec.push_back(y);
> xEVec.push_back(xE);
> yEVec.push_back(yE);
> }
> double alpha[2];
> double chi2;
> alpha[0]=1e-4;
> alpha[1]=1e2;
> CalculateChi2(xVec,yVec,yEVec,alpha);
> --> that works...
>
>
> However, once I want to execute the routine CalculateChi2 more than
> twice, by putting it inside a loop I get a weird error message:
> for (int i = 0; i<5; i++){
> chi2=CalculateChi2(xVec,yVec,yEVec,alpha);
> cout << "Chi2/Ndf " << chi2/xVec.size() << endl;
> }
> ----> OUTPUT <-------
> Processing littleHenry.C...
> Chi2/Ndf 528.202
> Chi2/Ndf 528.202
> Error: Can't call vector<double,allocator<double>
>
>> ::vector<double,allocator<double> >((class
>>
> vector<double>***&)148530456) in current scope littleHenry.C:34:
> Possible candidates are...
> (in vector<double,allocator<double> >)
> vector.dll -1:-1 0 public: vector<double,allocator<double> >
> vector<double,allocator<double> >::vector<double,allocator<double> >(void);
> vector.dll -1:-1 0 public: vector<double,allocator<double> >
> vector<double,allocator<double> >::vector<double,allocator<double>
>
>> (vector<double,allocator<double> >::size_type n,const double&
>>
> value=double());
> vector.dll -1:-1 0 public: vector<double,allocator<double> >
> vector<double,allocator<double> >::vector<double,allocator<double>
>
>> (const vector<double,allocator<double> >& x);
>>
> vector.dll -1:-1 0 public: vector<double,allocator<double> >
> vector<double,allocator<double> >::vector<double,allocator<double>
>
>> (vector<double,allocator<double> >::const_iterator
>>
> first,vector<double,allocator<double> >::const_iterator last);
> *** Interpreter error recovered ***
>
> I wonder if I somehow run out of the boundaries of the vector but that
> should not happen as they are not touched and treated as constants...
> Any ideas?
>
> Cheers,
> Stephan
>
>
Received on Sat Feb 27 2010 - 05:01:27 CET