Choose path for saving histogram

AryaStark · February 19, 2014, 1:13pm

Hi!

I would like to select the folder where I want to save a histogram.
Or to have just “Save As” file chooser.

Would that be possible with TGFileBrowser?
Could you please give me an example?

Thank you!
A

bellenot · February 19, 2014, 2:14pm

Hi,

[quote=“AryaStark”]I would like to select the folder where I want to save a histogram.
Or to have just “Save As” file chooser.[/quote]You can simply use the “SaveAs” context menu entry (but then you have to give the full path)

Cheers, Bertrand.

AryaStark · February 19, 2014, 2:33pm

Hi,

I’m already using TEveBrowser, and I want the users to specify a folder/path for saving histograms.
Maybe using the TFileBrowser?

I cannot specify the path myself because users (students) usually don’t have permission to write on C disk - and then they cannot save the histogram.

Thanks!

bellenot · February 19, 2014, 2:44pm

Well, I don’t understand what you mean, but anyway, you can customize the context menu (as shown in customContextMenu.C tutorial) and use a TGFileDialog…

Cheers, Bertrand.

AryaStark · February 20, 2014, 9:54am

Dear Bertrand,

Here is a picture of what I need:

http://oi59.tinypic.com/1zfpg7o.jpg

and I have a code for that helpPopUP.c which works fine!

BUT, when I try the same thing using TEveBrowser (when I call the popup window from the TEveBrowser) it has some problem with shared fmainframe space!

I have tried to do so in the example markTracks.c.

Could you please take a look?

Thank you!
helpPopUp.C (6.19 KB)
markTracks.c (6.61 KB)

bellenot · February 20, 2014, 10:06am

Hi,

You forgot to add

at the end of the makeGui() function

Cheers, Bertrand.

AryaStark · February 20, 2014, 3:23pm

Thank you very much! This solved my problem!

BUT now I have another one

This is my code:

fTextEntry994->SetText("C:/Users/astark/Histogram"); //user's input
---------------
void saveHistogram()
{
     pathSave=fTextEntry994->GetText();
     TFile *saveH2=new TFile(histName1,"RECREATE");
     saveH2->cd(pathSave);
     a->Write(); //a is TH1F
     saveH2->Close();
}

I just want to save my histogram in that place and I get the error:

Could you help me with this too?
Thank you!

bellenot · February 20, 2014, 4:28pm

Replace: saveH2->cd(pathSave);
By: gSystem->cd(pathSave);
Cheers, Bertrand.

AryaStark · February 20, 2014, 5:24pm

I’ve tried that, and I printed the current path (and that was OK), but in the end, histogram was saved in the previous place!
Do you maybe have other suggestions?

bellenot · February 20, 2014, 10:10pm

Try this way (obviously you will have to adapt it to your own code):

void saveHistogram() { TString histName1 = "histogram.root"; TString pathSave = "C:/Users/astark/Histogram"; if (!pathSave.EndsWith("/")) pathSave += "/"; TH1F *h1 = new TH1F("h1", "histo from a gaussian", 100, -3, 3); h1->FillRandom("gaus", 10000); TFile *saveH2 = TFile::Open(pathSave+histName1, "RECREATE"); h1->Write(); saveH2->Close(); delete saveH2; }
Cheers, Bertrand.

jfcaron · February 20, 2014, 11:17pm

There is a TSystem method that allows you to join directory names and file names without needing to check for “/” manually, and it does so for all platforms:

http://root.cern.ch/root/html/TSystem.html#TSystem:PrependPathName

E.g.:

root [0] gSystem->PrependPathName("/var/foo","myfile.root")
(const char* 0x7fc11c920b30)"/var/foo/myfile.root"
root [1] gSystem->PrependPathName("/var/foo/","myfile.root")
(const char* 0x7fc11cacf8a0)"/var/foo/myfile.root"

For some reason there is also “ConcatFileName” which has a better method name (shouldn’t these be just overloaded methods?), but unfortunately returns a pointer to a “new’ed” character array. PrependPathName is less likely to lead to memory leaks, according to my reading of the docs.

Jean-François

AryaStark · February 21, 2014, 11:20am

Thank you very much for your help!

Btw I’ve discovered that this line of code made the difference, and it’s not necessary to use cd() function.

   TFile *saveH2 = TFile::Open(pathSave+histName1, "RECREATE");

AryaStark · February 24, 2014, 8:50am

My program works very well on Windows, but on Linux every time when I click OK button I get this error:

[quote]*** Break *** segmentation violation
Error in : BadDrawable (invalid Pixmap or Window parameter) (TGTextEntry XID: 6291592, XREQ: 74)
TGTextEntry: 6291592

*** Break *** segmentation violation
Error in : BadDrawable (invalid Pixmap or Window parameter) (TGTextEntry XID: 6291592, XREQ: 66)
TGTextEntry: 6291592

*** Break *** segmentation violation
Error in : BadDrawable (invalid Pixmap or Window parameter) (TGTextEntry XID: 6291592, XREQ: 66)

TGTextEntry: 6291592
[/quote]

I have added the following lines of code (just for the pop up window):

fMainFrame1599->Connect("CloseWindow()","className", this, "ButtonOk()"); fMainFrame1599->DontCallClose(); fMainFrame1599->SetCleanup(kDeepCleanup);
and I get a crash on Windows when I click OK.

Could you please help me?