Detecting Elements of Sentence In Ruby - ruby

My aim is detecting simple elements in any sentence such as verb, noun or adjective. Is there any gem in Ruby for achieving that? For example:
They elected him president yesterday.
Output:
["subject","verb", "object", "predicative", adverbial"]

These are the only natural language processing options for Ruby that I know of.
Treat
Stanford Core NLP
Open NLP
Interestingly, they are all by the same person.
EDIT
Here is one more option that I found. It's a tutorial on n-gram analysis.
Natural Language Processing with Ruby: n-grams

I've used engtagger with good success in the past. It's ported from a Perl program called Lingua::EN::Tagger. It takes a bit of work to get it to do what you want, but I think it's the best tool available for this application (at least at the moment).

Related

software or algorithms to detect grammar units in texts

I'm not sure this is the right fit for stackoverflow but maybe you guys would suggest where to put this question otherwise but here it is anyway. Suppose I have a few sentences of a text like this:
John reads newspapers everyday. Right now he has just finished reading
one. He will read another one and might even read a small book
tomorrow.
This small extract contains the following grammar units:
present simple (reads)
present perfect (has finished)
future simple (will read)
modal verb may
Do you know of any software, algorithm or study that defines rules for identifying these grammar patterns?
Read this also if you are going to use Ruby than you can use TreeTop or find the equivalent parser in other programming language.
NTLK is a natural language parser for python, it works by tagging words. You can look at some examples here. It creates a parse-tree, which are very useful for these types of problems.
I haven't seen it distinguish between simple and perfect, but it could be modified to do so.

How to use Stanford parser to generate the English sentence from given segmented nodes

I am trying to develop a Sinhala (My native language) to English translator.
Still I am thinking for an approach.
If I however parse a sentence of my language, then can use that for generating english sentence with the help of stanford parser. Or is there any other method you can recommend.
And I am thinking of a bottom up parser for my language, but still have no idea how to implement. Any suggestions for steps I can follow.
Thanks
Mathee
If you have enough amounts of bilingual corpora then the best thing you can do is to train a model using an existing statistical machine translation system like Moses. Modern phrase-based SMT systems resemble a reverse parsing mechanism in the sense that they find the most probable combination of target-language phrases for translating a specific source-language sentence. More information in this Wikipedia article.

How to reverse use a nlp parser to generate sentences

I am trying to develop a Sinhala (My native language) to English translator. Still I am thinking for an approach.
If I however parse a sentence of my language, then can I use that for generating english sentence with the help of stanford parser or any other parser. Or is there any other method you can recommend.
And I am thinking of a bottom up parser for my language, but still have no idea how to implement. Any suggestions for steps I can follow.
Thanks Mathee
This course on Coursera may help you implement a translator. From what I know based on that course, you can use a training set tagged by parts of speech (i.e. noun, verb, etc.) and use that training test to parse other sentence. I suggest looking into hidden Markov models.
My Pyramids parser is an unconventional single-sentence parser for English. (It is capable of parsing other languages too, but a grammar must be specified.) The parser can not only parse English into parse trees, but can convert back and forth between parse trees and word-level semantic graphs, which are graphs that describe the semantic relationships between all the words in a sentence. The correct word order is reconstructed based on the contents of the graph; all that needs to be provided, other than the words and their relationships, is the type of sentence (statement, question, command) and the linguistic category of each word (noun, determiner, verb, etc.). From there it is straight-forward to join the tokens of the parse tree into a sentence.
The parser is a (very early) alpha pre-release, but it is functional and actively maintained. I am currently using it to translate back and forth between English and an internal semantic representation used by a conversational agent (a "chat bot", but capable of more in-depth language understanding). If you decide to use the parser, do let me know. I will be happy to provide any assistance you might need with installing, using, or improving it.

Is there a framework for writing phrase structure rules out there that is opensource?

I've worked with the Xerox toolchain so far, which is powerful, not opensource, and a bit overkill for my current problem. Are there libraries that allow my to implement a phrase structure grammar? Preferably in ruby or lisp.
AFAIK, there's no open-source Lisp phrase structure parser available.
But since a parser is actually a black box, it's not so hard to make your application work with a parser written in any language, especially as they produce S-expressions as output. For example, with something like pfp you can just pipe your sentences as strings to it, then read and process the resulting trees. Or you can wrap a socket server around it and you'll get a distributed system :)
There's also cl-langutils, that may be helpful in some basic NLP tasks, like tokenization and, maybe, POS tagging. But overall, it's much less mature and feature rich, than the commonly used packages, like Stanford's or OpenNLP.

Ruby Text Analysis

Is there any Ruby gem or else for text analysis? Word frequency, pattern detection and so forth (preferably with an understanding of french)
the generalization of word frequencies are Language Models, e.g. uni-grams (= single word frequency), bi-grams (= frequency of word pairs), tri-grams (=frequency of world triples), ..., in general: n-grams
You should look for an existing toolkit for Language Models — not a good idea to re-invent the wheel here.
There are a few standard toolkits available, e.g. from the CMU Sphinx team, and also HTK.
These toolkits are typically written in C (for speed!! because you have to process huge corpora) and generate standard output format ARPA n-gram files (those are typically a text format)
Check the following thread, which contains more details and links:
Building openears compatible language model
Once you generated your Language Model with one of these toolkits, you will need either a Ruby Gem which makes the language model accessible in Ruby, or you need to convert the ARPA format into your own format.
adi92's post lists some more Ruby NLP resources.
You can also Google for "ARPA Language Model" for more info
Last not least check Google's online N-gram tool. They built n-grams based on the books they digitized — also available in French and other languages!
The Mendicant Bug: NLP Resources for Ruby
contains lots of useful Ruby NLP links.
I had tried using the Ruby Linguistics stuff a long time ago, and remember having a lot of problems with it... I don't recommend jumping into that.
If most of your text analysis involves stuff like counting ngrams and naive Bayes, I recommend just doing it on your own. Ruby has pretty good basic libraries and awesome support for regexes, so this should not be that tricky, and it will be easier for you to adapt stuff to the idiosyncrasies of the problem you are trying to solve.
Like the Stanford parser gem, its possible to use Java libraries that solve your problem from within Ruby, but this can be tricky, so probably not the best way to solve a problem.
I wrote the gem words_counted for this reason. You can see a demo on rubywordcount.com. It has a lot of the analysis features you mention, and a host more. The API is well documented and can be found in the readme on Github.

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