earley-parser | 易学教程

Using integers/dates as terminals in NLTK parser

阅读更多关于 Using integers/dates as terminals in NLTK parser

问题 I'm trying to use the Earley parser in NLTK to parse sentences such as: If date is before 12/21/2010 then serial = 10 To do this, I'm trying to write a CFG but the problem is I would need to have a general format of dates and integers as terminals, instead of the specific values. Is there any ways to specify the right hand side of a production rule as a regular expression, which would allow this kind of processing? Something like: S -> '[0-9]+' which would handle all integers. 回答1: For this

Earley cannot handle epsilon-states already contained in chart

阅读更多关于 Earley cannot handle epsilon-states already contained in chart

问题 I have implemented the Earley parser using a queue to process states. The queue is seeded with the top-level rule. For each state in the queue, one of the operations (prediction, scanning, completion) is performed by adding new states to the queue. Duplicate states are not added. The problem I am having is best described with the following grammar: When parsing A , the following happens: As you can tell, A will not be fully resolved . This is because the completion with the epsilon state will

Using integers/dates as terminals in NLTK parser

阅读更多关于 Using integers/dates as terminals in NLTK parser

I'm trying to use the Earley parser in NLTK to parse sentences such as: If date is before 12/21/2010 then serial = 10 To do this, I'm trying to write a CFG but the problem is I would need to have a general format of dates and integers as terminals, instead of the specific values. Is there any ways to specify the right hand side of a production rule as a regular expression, which would allow this kind of processing? Something like: S -> '[0-9]+' which would handle all integers. For this to work, you'll need to tokenize the date so that each digit and slash is a separate token. from nltk.parse