Root on jupyter notebook does not plot graphics in C++

ROOT
1

Dear all,
I am trying to use ROOT through a jubyter notebook in C++, however it does not plot any graphics, although it creates the object. Any ideas?

I have compiled root 6.26.10 with python 3.8.10
I used gcc 9.4.0
I have download JsRoot730 and provided the directory to CMAKE_INSTALL_JSROOTDIR (however I am not sure if this is the correct procedure).
My system is Ubuntu 20.04

Thank you in advance,
Costas

2

Hi Costas,

You do not need to install JSROOT extra - it is provided with ROOT already.
Also for ROOT 6.26 base JSROOT version is 6.3 - versions 7 may not work.

If after plain ROOT compilation JSROOT graphics in jupyter notebook does not work - please check output in browser console (activated with Ctrl-Shift-I)

Regards,
Sergey

3

Hi Sergey,

Thank you for your reply. I have compiled again root without the external JSROOT package.

Also I tried to run it through a conda environment, but the graphics still do not display.
The error message in the browser console is as follows:
“Failed to fetch ipywidgets through the “jupyter.widget.control” comm channel, fallback to fetching individual model state. Reason: Control comm was closed too early”

However, ipywidgets is installed as you can see below:
jupyter --version

Selected Jupyter core packages…
IPython : 8.10.0
ipykernel : 6.19.2
ipywidgets : 8.0.4
jupyter_client : 7.4.9
jupyter_core : 5.2.0
jupyter_server : 1.23.4
jupyterlab : 3.5.3
nbclient : 0.5.13
nbconvert : 6.5.4
nbformat : 5.7.0
notebook : 6.5.2
qtconsole : 5.4.0
traitlets : 5.7.1

4

Hi Costas,

It is definitely some configuration problems of jupyter.
Are you using jupyter lab or jupyter notebook?

I have a cases when some widgets from jupyter tutorials (not ROOT) were working with notebook, but not working with lab.
Try both to see difference.

Regards,
Sergey