How do you make NLTK draw() trees that are inline in iPython/Jupyter
Based on this answer:
import os
from IPython.display import Image, display
from nltk.draw import TreeWidget
from nltk.draw.util import CanvasFrame
def jupyter_draw_nltk_tree(tree):
cf = CanvasFrame()
tc = TreeWidget(cf.canvas(), tree)
tc['node_font'] = 'arial 13 bold'
tc['leaf_font'] = 'arial 14'
tc['node_color'] = '#005990'
tc['leaf_color'] = '#3F8F57'
tc['line_color'] = '#175252'
cf.add_widget(tc, 10, 10)
cf.print_to_file('tmp_tree_output.ps')
cf.destroy()
os.system('convert tmp_tree_output.ps tmp_tree_output.png')
display(Image(filename='tmp_tree_output.png'))
os.system('rm tmp_tree_output.ps tmp_tree_output.png')
Little slow, but does the job. If you're doing it remotely, don't forget to run your ssh session with -X
key (like ssh -X [email protected]
) so that Tk could initialize itself (no display name and no $DISPLAY environment variable
-kind of error)
UPD: it seems like last versions of jupyter and nltk work nicely together, so you can just do IPython.core.display.display(tree)
to get a nice-looking tree-render embedded into the output.
2019 Update:
This runs on Jupyter Notebook:
from nltk.tree import Tree
from IPython.display import display
tree = Tree.fromstring('(S (NP this tree) (VP (V is) (AdjP pretty)))')
IPython.core.display.display(tree)
Requirements:
- NLTK
- Ghostscript