Re: convert ntuple to histogram

Hi jeehoon,

You forgot to hit reply all. ;)

On 13 September 2010 13:30, <jhkim_at_physics.utexas.edu> wrote:
> Hi Suvayu,
>
> Thank you so much for help.
>
> I have two variables, x and y, in the ntuple plot (ntuple->Draw("x:y")).
> How can I convert this 2d like plot into histogram?
>

If you refer to the html documentation page I pointed to earlier you'll see that you can specify binning of the histogram with the Draw command.

So try something like this,

ntuple->Draw("x:y>>htemp(100,0,1000,50,0,500)");

This will create a 2D histogram with xrange from 0,1000 with 100 bins and yrange 0,500 with 50 bins.

Read the html page I cited earlier, TTree::Draw() is a very versatile method. You can do many other cool tricks with it.

> Best,
>
> jeehoon
>

GL

>
> Quoting suvayu ali <fatkasuvayu_at_gmail.com>:
>
>> On 13 September 2010 11:15,  <jhkim_at_physics.utexas.edu> wrote:
>>>
>>> Hi,
>>>
>>> Is there any way to directly convert ntuple into histogram?
>>>
>>
>> Can't you just use,
>>
>> myTNtuple->Draw("var1>>htemp");
>> TH1F* histo =  (TH1F*)gPad->GetPrimitive("htemp");
>>
>> You can see http://root.cern.ch/root/html/TTree.html#TTree:Draw for
>> more details.
>>
>>> Best,
>>>
>>> Jeehoon
>>>
>>
>> --
>> Suvayu
>>
>> Open source is the future. It sets us free.
>>
>
>
>
>

-- 
Suvayu

Open source is the future. It sets us free.