Cannot load ascii file

atha.stam · August 16, 2012, 9:51pm

Allό to everyone!

I am trying to reproduce a simple spectrum, by loading an ascii file(with only one column) and creating the relevant histogram.
I am using Rene Brun’s code, but it doesn’t seem to be working in my case.

The code I am using is

[code]#include "Riostream.h"
void basic() {
// Read data from an ascii file and create a root file with an histogram and an ntuple.
// see a variant of this macro in basic2.C
//Author: Rene Brun

// read file $ROOTSYS/tutorials/tree/basic.dat
// this file has 3 columns of float data
TString dir = gSystem->UnixPathName(gInterpreter->GetCurrentMacroName());
dir.ReplaceAll(“basic.C”,"");
dir.ReplaceAll("/./","/");
ifstream in;
in.open(Form("%sD800M655.dat",dir.Data()));

Float_t x;
Int_t nlines = 0;
TFile *f = new TFile(“D800M655.root”,“RECREATE”);
TH1F *h1 = new TH1F(“h1”,“x distribution”,100,-4,4);
TNtuple *ntuple = new TNtuple(“ntuple”,“data from ascii file”,“x”);

while (1) {
in >> x;
if (!in.good()) break;
if (nlines < 5) printf(“x=%8f”,x);
h1->Fill(x);
ntuple->Fill(x);
nlines++;
}
printf(" found %d points\n",nlines);

in.close();

f->Write();
}
[/code]

Running this script produces the message
found 0 points

Any ideas on what may be wrong?

Thanks a lot in advance!

Pepe_Le_Pew · August 16, 2012, 10:18pm

Does the “D800M655.dat” file exist in the same subdirectory where the “basic.C” macro?
If yes, check the very first line of it as it breaks on it.
If this doesn’t help, attach that data file (rename it adding a “.txt” in the end) so that we can have a look at it.

atha.stam · August 16, 2012, 10:29pm

Both basic.c and D800M655.dat are on the same directory.
I am attaching .txt file

P.S.:I also tried with the .txt in case there is a bug with .dat files, but it didn’t work.
D800M655.txt (3 KB)

Pepe_Le_Pew · August 16, 2012, 10:34pm

Do you have “basic.c” or “basic.C”?
With your “D800M655.dat” file and your “basic.C” macro, I Immediately get … “found 1024 points”.

Note, you should have:

TH1F *h1 = new TH1F("h1","x distribution", 100, 0, 10000); ... if (nlines < 5) printf("x=%8f\n",x);

atha.stam · August 16, 2012, 10:45pm

I have basic.c, which is the macro I copied from Rene…
I changed it with basic.C and I also get 1024 points.
The thing is that there is no histogram.
I added

but I don’t get any histo, whatsoever…

Pepe_Le_Pew · August 16, 2012, 10:48pm

Try:
root [0] .x basic.C
root [1] h1->Draw()
root [2] ntuple->Draw(“x”)

BTW. Note that the exact name “basic.C” is required by the line:
dir.ReplaceAll(“basic.C”,"");

Anyhow, usually “.c” means C code, while “.C” means C++ code.

atha.stam · August 16, 2012, 10:56pm

I get a printed canvas!
I tried those lines in the macro file but it’s not working.
Is there a way to print it, using lines in the excecutable macro?

Pepe_Le_Pew · August 16, 2012, 10:59pm

[code]…
f->Write();

TCanvas *c = new TCanvas(“c”, “c”);
h1->Draw();
c->SetLogy(1);
c->SaveAs(“c.pdf”);
}[/code]

atha.stam · August 16, 2012, 11:07pm

It’s not working…
I also added

just in case but this isn’t working either…

Pepe_Le_Pew · August 16, 2012, 11:19pm

Try the attached “basic.C” file. I get: root [0] .x basic.C x=0.000000 x=0.000000 x=0.000000 x=0.000000 x=0.000000 found 1024 points Info in <TCanvas::Print>: pdf file c.pdf has been created
basic.C (1.2 KB)

atha.stam · August 16, 2012, 11:23pm

It is working!!!
Thank you so much once again!
However, I can’t see the difference;perhaps it is too late

Thank you, thank you, thank you!!!

Pepe_Le_Pew · August 16, 2012, 11:27pm

Note: you can also run this macro as ACLiC precompiled. Try: root [0] .x basic.C++ P.S. maybe you will need to replace “ifstream in;” with “std::ifstream in;” (I’ve forgotten to fix it in the file attached in my previous post).

atha.stam · August 17, 2012, 10:26am

Now I found another problem.
The histo that’s produced is not the proper.
I don’t know why.

So what I did was to make a new .dat file, with two columns x(channel number), y(weight).
The code I used is the following:

[code]#include
#include
#include

#include “TString.h”
#include “TSystem.h”
#include “TInterpreter.h”
#include “TFile.h”
#include “TH1.h”
#include “TNtuple.h”
#include “TCanvas.h”

void basic() {
// Read data from an ascii file and create a root file with an histogram and an ntuple.
// see a variant of this macro in basic2.C
//Author: Rene Brun

// read file $ROOTSYS/tutorials/tree/basic.dat
// this file has 3 columns of float data
TString dir = gSystem->UnixPathName(gInterpreter->GetCurrentMacroName());
dir.ReplaceAll(“basic.C”,"");
dir.ReplaceAll("/./","/");
ifstream in;
in.open(Form("%sFirstStripSignal.dat",dir.Data()));

Float_t x,y;
Int_t nlines = 0;
TFile *f = new TFile(“FirstStripSignal.root”,“RECREATE”);
TH1F *h1 = new TH1F(“h1”,“x distribution”, 1024, 1, 1024);
TNtuple *ntuple = new TNtuple(“ntuple”,“data from ascii file”,“x:y”);

while (1) {
in >> x >> y;
if (!in.good()) break;
if (nlines < 5) printf(“x=%8f, y=%8f/n”,x);
h1->Fill(x,y);
ntuple->Fill(x,y);
nlines++;
}
printf(" found %d points\n",nlines);

in.close();

f->Write();

TCanvas *c = new TCanvas(“c”, “c”);
h1->Draw();
c->SetLogy(0);
c->SaveAs(“c.pdf”);
}[/code]

In this case, someone can reproduce a spectrum in root!

Pepe_Le_Pew · August 17, 2012, 10:59am

Try with: TH1F *h1 = new TH1F("h1","x distribution", 1024, 1, 1025); ... if (nlines < 5) printf("x=%8f, y=%8f\n", x, y); or with: TH1F *h1 = new TH1F("h1","x distribution", 1024, 0.5, 1024.5); ... if (nlines < 5) printf("x=%8f, y=%8f\n", x, y);

atha.stam · August 17, 2012, 11:29am

Perhaps you didn’t see the code
I’ve managed to get the spectrum

I will attach the spectrum file and the spectrum itself.

Now I have another problem…
I want to fit a specific range and get in the stat box the fitting parameters(centroid and FWHM).
I have tried several lines I found on the web but nothing seems to work.
Here comes the code I am using:

[code]#include
#include
#include

#include “TString.h”
#include “TSystem.h”
#include “TInterpreter.h”
#include “TFile.h”
#include “TH1.h”
#include “TNtuple.h”
#include “TCanvas.h”

void basic() {
// Read data from an ascii file and create a root file with an histogram and an ntuple.
// see a variant of this macro in basic2.C
//Author: Rene Brun

// read file $ROOTSYS/tutorials/tree/basic.dat
// this file has 3 columns of float data
TString dir = gSystem->UnixPathName(gInterpreter->GetCurrentMacroName());
dir.ReplaceAll(“basic.C”,"");
dir.ReplaceAll("/./","/");
ifstream in;
in.open(Form("%sFirstStripSignal.dat",dir.Data()));

Float_t x,y;
Int_t nlines = 0;
TFile *f = new TFile(“FirstStripSignal.root”,“RECREATE”);
TH1F *h1 = new TH1F(“h1”,“x distribution”, 1024, 1, 1024);
TNtuple *ntuple = new TNtuple(“ntuple”,“data from ascii file”,“x:y”);

while (1) {
in >> x >> y;
if (!in.good()) break;
if (nlines < 5) printf(“x=%8f, y=%8f/n”,x);
h1->Fill(x,y);
ntuple->Fill(x,y);
nlines++;
}
printf(" found %d points\n",nlines);

in.close();

f->Write();

gStyle->SetOptStat(1111);

TCanvas *c = new TCanvas(“c”, “c”);
h1->Draw();
h1->Fit(“gaus”,“W”,NULL,200,400);

//TPaveStats st = ((TPaveStats)(h1->GetListOfFunctions()->FindObject(“stats”)));

c->SetLogy(0);
c->SaveAs(“c.pdf”);
}[/code]
c.pdf (21.1 KB)
FirstStripSignal.txt (7.5 KB)

Pepe_Le_Pew · August 17, 2012, 11:46am

gStyle->SetOptFit(1111);

atha.stam · August 17, 2012, 11:50am

That was my first option, but it doesn’t seem to be working…

Pepe_Le_Pew · August 17, 2012, 12:04pm

basic.C (1.6 KB)

atha.stam · August 17, 2012, 12:30pm

Yessssssssssssssssssssssssss!!!
I can’t really find words to thank you!!!
You are awesome