python - use tkinter for nltk draw inside of jupyter notebook -

i'm trying draw graph (inline) of nltk inside of jupyter-notebook. got error:

tclerror: no display name , no $display environment variable 

i have tried set $display different values:

$env display=0.0 # or $env display=inline # or $env display= 

but got error (or similar):

tclerror: couldn't connect display "0.0" 

here code https://github.com/hyzhak/nltk-experiments/blob/master/main.ipynb last cell.

environment: official anaconda3 docker -- continuumio/anaconda3:4.4.0 https://github.com/continuumio/docker-images. nltk==3.2.3 inside.

python 3.6.1 |anaconda 4.4.0 (64-bit)| (default, may 11 2017, 13:09:58)  type "copyright", "credits" or "license" more information.  ipython 5.3.0 -- enhanced interactive python. 

how solve error , inline nltk graph inside of jupyter notebook?

update 1

http://www.nltk.org/_modules/nltk/draw/tree.html#draw_trees according sources of nltk tree draw uses tkinter.

update 2

i have asked same question in official nltk github repository https://github.com/nltk/nltk/issues/1765

update 3

i think reason of error headless host (docker). have installed xvfb seems note enough.

run apt-get install -y xvfb 

solution

i thought xvfb launched default should run explicitly. after have launched make screenshots of nltk tree graph.

import os import nltk ipython.display import image  chunkgram = r"""chunk: {<rb.?>*<vb.?>*<nnp>+<nn>?}""" chunkparser = nltk.regexpparser(chunkgram)  tagged = [('tonight', 'nn'), ('we', 'prp'), ('are', 'vbp'), ('comforted', 'vbn'), ('by', 'in'), ('the', 'dt'), ('hope', 'nn'), ('of', 'in'), ('a', 'dt'), ('glad', 'jj'), ('reunion', 'nn'), ('with', 'in'), ('the', 'dt'), ('husband', 'nn'), ('who', 'wp'), ('was', 'vbd'), ('taken', 'vbn'), ('so', 'rb'), ('long', 'rb'), ('ago', 'rb'), (',', ','), ('and', 'cc'), ('we', 'prp'), ('are', 'vbp'), ('grateful', 'jj'), ('for', 'in'), ('the', 'dt'), ('good', 'jj'), ('life', 'nn'), ('of', 'in'), ('coretta', 'nnp'), ('scott', 'nnp'), ('king', 'nnp'), ('.', '.')] chunked = chunkparser.parse(tagged) nltk.draw.tree.treeview(chunked)._cframe.print_to_file('output.ps') os.system('convert output.ps output.png')  image(filename='output.png')  

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