(base) ling388-24$ more g2.txt
S -> NP VP
NP -> DT NN
NP -> NP PP_possession
VP -> VBD NP PP_instrument
VP -> VBD NP
PP_possession -> IN_possession NP  
PP_instrument -> IN_instrument NP
NP -> 'John'
NP -> 'Mary'
DT -> 'a'
DT -> 'the' 
NN -> 'boy' 
NN -> 'man' 
NN -> 'telescope' 
IN_possession -> 'with'  
IN_instrument -> 'with'  
VBD -> 'saw'
(base) ling388-24$ python


(base) ling388-24$ python
Python 3.9.16 | packaged by conda-forge | (main, Feb  1 2023, 21:38:11) 
[Clang 14.0.6 ] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import nltk
>>> parser2 = nltk.ChartParser(nltk.CFG.fromstring(open('g2.txt').read()))
>>> for parse in parser2.parse(nltk.word_tokenize("a man with a telescope saw the boy")):
...     parse.pretty_print()
... 
                                S                                    
                   _____________|__________________________           
                  NP                                       |         
      ____________|_____________                           |          
     |                    PP_possession                    VP        
     |             _____________|________               ___|___       
     NP           |                      NP            |       NP    
  ___|___         |              ________|______       |    ___|___   
 DT      NN IN_possession       DT              NN    VBD  DT      NN
 |       |        |             |               |      |   |       |  
 a      man      with           a           telescope saw the     boy

>>> for parse in parser2.parse(nltk.word_tokenize("a man with a telescope saw the boy")):
...     parse.draw()
... 
>>> 



>>> for parse in parser2.parse(nltk.word_tokenize("a man with a telescope saw the boy with a telescope")):
...     parse.pretty_print()
... 
                                                       S                                                       
                   ____________________________________|___________                                             
                  |                                                VP                                          
                  |                                     ___________|________                                    
                  NP                                   |                    NP                                 
      ____________|_____________                       |        ____________|_____________                      
     |                    PP_possession                |       |                    PP_possession              
     |             _____________|________              |       |             _____________|________             
     NP           |                      NP            |       NP           |                      NP          
  ___|___         |              ________|______       |    ___|___         |              ________|______      
 DT      NN IN_possession       DT              NN    VBD  DT      NN IN_possession       DT              NN   
 |       |        |             |               |      |   |       |        |             |               |     
 a      man      with           a           telescope saw the     boy      with           a           telescope

                                                       S                                                       
                   ____________________________________|___________                                             
                  NP                                               VP                                          
      ____________|_____________                        ___________|______________________                      
     |                    PP_possession                |       |                    PP_instrument              
     |             _____________|________              |       |             _____________|________             
     NP           |                      NP            |       NP           |                      NP          
  ___|___         |              ________|______       |    ___|___         |              ________|______      
 DT      NN IN_possession       DT              NN    VBD  DT      NN IN_instrument       DT              NN   
 |       |        |             |               |      |   |       |        |             |               |     
 a      man      with           a           telescope saw the     boy      with           a           telescope

>>> parser2 = nltk.ChartParser(nltk.CFG.fromstring(open('g2.txt').read()))
>>> parser3 = nltk.ChartParser(nltk.CFG.fromstring(open('g3.txt').read()))
>>> parser3
<nltk.parse.chart.ChartParser object at 0x1684bb0a0>
>>> cfg = nltk.CFG.fromstring(open('g3.txt').read())
>>> cfg
<Grammar with 13 productions>
>>> for parse in parser3.parse(nltk.word_tokenize("the chicken is ready to eat")):
...     parse.draw()
... 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/sandiway/opt/anaconda3/lib/python3.9/site-packages/nltk/parse/chart.py", line 1474, in parse
    chart = self.chart_parse(tokens)
  File "/Users/sandiway/opt/anaconda3/lib/python3.9/site-packages/nltk/parse/chart.py", line 1432, in chart_parse
    self._grammar.check_coverage(tokens)
  File "/Users/sandiway/opt/anaconda3/lib/python3.9/site-packages/nltk/grammar.py", line 665, in check_coverage
    raise ValueError(
ValueError: Grammar does not cover some of the input words: "'chicken'".
>>> parser3 = nltk.ChartParser(nltk.CFG.fromstring(open('g3.txt').read()))
>>> for parse in parser3.parse(nltk.word_tokenize("the chicken is ready to eat")):
...     parse.draw()
... 
>>> for parse in parser3.parse(nltk.word_tokenize("the chicken is ready to eat")):
...     parse.pretty_print()
... 
                      S                           
      ________________|____                        
     |                     VP                     
     |            _________|___                    
     |           |            ADJP                
     |           |     ________|____               
     |           |    |             S             
     |           |    |     ________|___           
     |           |    |    |            VP        
     |           |    |    |    ________|___       
     NP          |    |    |   |            VP    
  ___|_____      |    |    |   |         ___|___   
 DT        NN   VBZ   JJ   NP  TO       VB      NP
 |         |     |    |    |   |        |       |  
the     chicken  is ready ...  to      eat     ...

>>> Segmentation fault: 11
(base) ling388-24$