Drawing smoothly contours

Hi, is there any way to draw contours without leaving some filled bins empty? I mean, I have a 3d plot drawed but when I try to plot its projection with the cont0 option, there some white space. I read the data from a NTuple, the code for drawing the 3dgraph is this one: ntuple->Draw(“y:x:z:E”,"",“colz”); (x,y, z position weighted with energy) and for the projections I draw them with: ntuple->Draw(“x:z”,“E”,“cont0z”);

You can see the result of doing this in the attached image. I would expect a continuous line also in th2 2d histo but that’s no the case. Is there anyway to draw those empty spaces or either use a 2d polymarker weighted with the energy?

Sorry if I’m not clear, my english is not that good and thanks in advance!


what do you get with



I attach an image with the output using “colz”. That way I guess I could do it but, compared with the contour drawing option, I find kind of ugly. It’s just an aesthetics thing but it would be great if this could be made using the contour option. Thanks.

cont0z try to find the best contour. The algorithm may encouter some difficulties if the contour are not well defined.
try with CONT4

I tried it but it just works the same (with the exception than now all the background is purple, I guess it could be fixed using a transfer function), I still have these empty spaces.

So it means the contour algorithms are not able to find a continuous path. It may append if the contour level you choose are within one bin… may be try to change the contour levels you see. The one by default might be such that they are not possible to be continuous. Have you also tried to increase the number of bins of your 2d histo ? this might help too.