Drawing rectangle

[1116]

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ROOT Version: 5.34/36
Platform: lxplus
Compiler: Not Provided
___After plotting a 2D histogram, I want to draw a rectangel in the plot to highlight some important information. How would I be able to do that?

[Dilicus]

Hi,
try to use the TBox class.

Cheers,
Stefano

[1116]

Hi Stefano,

Thank you for your suggestion. When I use TBox in my graph, it blocks whatever orginally was in there. But I don’t want that. I just want the edge of the box so that whatever orginally was there could remain there. Do you have other suggestions? Thanks.

Cheers,
QC

[Dilicus]

You can use the option inherited by TAttLine and TAttFill.
Try

box->SetFillAlphaColor(0,0);
box->SetLineColor(kRed);

Look at
TBox::SetFillColorAlpha()
TBox:SetLineColor()

Cheers,
Stefano

[1116]

Thank you. Unfortunately I’ve tried

Box=ROOT.TBox(-50,100,50,200)
Box.Draw()
Box.SetFillColorAlpha(0,0)
Box.SetLineColor(ROOT.kRed)

and also

Box=ROOT.TBox(-50,100,50,200)
Box.SetFillColorAlpha(0,0)
Box.SetLineColor(ROOT.kRed)
Box.Draw()

but neither of these works. Could you write out explicitly the code I need to draw a transparent box? Thanks.

Cheers,
QC

[Dilicus]

This should work

box->SetLineColor(kRed);
box->SetFillStyle(0);

Then you can also change the option for the line width

box->SetLineWidth(2);

Moreover, the coordinates of the box should be between 0 and 1, but about this I’m not so sure

Stefano

[1116]

It works. Thank you!

QC