I just started learning how to use mahout. I'm not a java programmer however, so I'm trying to stay away from having to use the java library.
I noticed there is a shell tool regexconverter. However, the documentation is sparse and non instructive. Exactly what does specifying a regex option do, and what does the transformer class and formatter class do? The mahout wiki is marvelously opaque. I'm assuming the regex option specifies what counts as a "unit" or so.
The example they list is of using the regexconverter to convert http log requests to sequence files I believe. I have a csv file with slightly altered http log requests that I'm hoping to convert to sequence files. Do I simply change the regex expression to take each entire row? I'm trying to run a Bayes classifier, similar to the 20 newsgroups example which seems to be done completely in the shell without need for java coding.
Incidentally, the arff.vector command seems to allow me to convert an arff file directly to vectors. I'm unfamiliar with arff, thought it seems to be something I can easily convert csv log files into. Should I use this method instead, and skip the sequence file step completely?
Thanks for the help.
Related
I'm trying to extract data from the PennTreeBank, Wall Street Journal corpus. Most of it already has the parse trees, but some of the data is only tagged.
i.e. wsj_DDXX.mrg and wsj_DDXX.pos files.
I would like to use the already parsed trees and tagged data in these files so as not to use the parser and taggers within CoreNLP, but I still want the output file format that CoreNLP gives; namely, the XML file that contains the dependencies, entity coreference, and the parse tree and tagged data.
I've read many of the java docs but I cannot figure out how to get it the way I described.
For POS, I tried using the LexicalizedParser and it allows me to use the tags, but I can only generate an XML file with the some of the information I want; there is no option for coreference or generating the parse trees. To get it to correctly generate the sub-optimal XML files here, I had to write a script to get rid of all of the brackets within the files. This is the command I use:
java -cp "*" edu.stanford.nlp.parser.lexparser.LexicalizedParser -outputFormat typedDependenciesCollapsed,wordsAndTags -outputFilesExtension xml -outputFormatOptions xml -writeOutputFiles -outputFilesDirectory my\dir -tokenized -tagSeparator / -tokenizerFactory edu.stanford.nlp.process.WhitespaceTokenizer -tokenizerMethod newCoreLabelTokenizerFactory edu/stanford/nlp/models/lexparser/englishPCFG.ser.gz my\wsj\files\dir
I also can't generate the data I would like to have for the WSJ data that already has the trees. I tried using what is said here and I looked at the corresponding Javadocs. I used the command similar to what is described. But I had to write a python program to retrieve the stdout data resulting from analyzing each file and wrote it into a new file. This resulting data is only a text file with the dependencies and is not in the desired XML notation.
To summarize, I would like to use the POS and tree data from these PTB files in order to generate a CoreNLP parse corresponding to what would occur if I used CoreNLP on a regular text file. The pseudo command would be like this:
java -cp "*" edu.stanford.nlp.pipeline.CoreNLP -useTreeFile wsj_DDXX.mrg
and
java -cp "*" edu.stanford.nlp.pipeline.CoreNLP -usePOSFile wsj_DDXX.pos
Edit: fixed a link.
Yes, this is possible, but a bit tricky and there is no out of the box feature that can do this, so you will have to write some code. The basic idea is to replace the tokenize, ssplit and pos annotators (and in case you also have trees the parse annotator) with your code that loads these annotations from your annotated files.
On a very high level you have to do the following:
Load your trees with MemoryTreebank
Loop through all the trees and for each tree create a sentence CoreMap to which you add
a TokensAnnotation
a TreeAnnotation and the SemanticGraphCoreAnnotations
Create an Annotation object with a list containing the CoreMap objects for all sentences
Run the StanfordCoreNLP pipeline with the annotators option set to lemma,ner,dcoref and the option enforceRequirements set to false.
Take a look at the individual annotators to see how to add the required annotations. E.g. there is a method in ParserAnnotatorUtils that adds the SemanticGraphCoreAnnotations.
I want to use package:intl to make multi lang html page.
I have seen example/basic_example.dart but don't find document of message_lookup_by_library.dart, intl_helpers.
Is there a simple example use package:intl.
Parts of that are still work in progress, e.g. there should be an update so that plurals and genders work in the next few days. To see the basic workflow, take a look at the intl/test/message_extraction directory and specifically message_extraction_test.dart That does a round-trip extraction, translation, code generation, and running the result. The end result is roughly what you see in basic_example.dart, but it actually does the intermediate steps to produce that.
That test uses a trivial JSON format for output and the translations are hard-coded. You could manually translate things using that format, but for real usage you would probably want to use a real translation tool and a format that it understood. There is a little bit of documentation at http://api.dartlang.org/docs/releases/latest/intl/Intl.html but for the time being you're probably stuck looking at the code and/or asking questions.
I am developing a project on wordnet-based document summarizer.in that i need to extract collocations. i tried to research as much as I could, but since i have not worked with Mahout before I am having difficulty in understanding how CollocDriver.java works (in API context)
while scouring through the web, i landed on this :
Mahout Collocations
this is the problem: i have a POSTagged input text. i need to identify collocations in it.i have got collocdriver.java code..now i need to know how do i use it? whether to use generateAllGrams() method or only generateCollocations() method is enough for my subtask within my summarizer..??
and most importantly HOW to use it? i raise this question coz I admit, i dont know the API well,
i also got a grepcode version of collocdriver the two implementations seem to be slightly different..the inputs are in string for the grepcode version and in the form of Path object in the original...
my questions: what is configuration object in input params and how to use it?? will the source / destn will be in string (as in grepcode) or Path (as in original)??
what will be the output?
i have done some further R & D on collocdriver program...i found out that it uses a sequence file and then vector generation...i wanna know how this sequence file / vector generation works..plz help..
To get collocation using mahout,u need to follow some simple steps
1) You must make a sequence file from ur input text file.
/bin/mahout seqdirectory -i /home/developer/Desktop/colloc/ -o /home/developer/Desktop/colloc/test-seqdir -c UTF-8 -chunk 5
2)There are two ways to generate collocations from a sequence file.
a)Convert sequence file to sparse vector and find out the collocation
b)Directly find out the collocation from the sequence file (with out creating the sparse vector)
3)Here i am considering choice b.
/bin/mahout org.apache.mahout.vectorizer.collocations.llr.CollocDriver -i /home/developer/Desktop/colloc/test-seqdir -o /home/developer/Desktop/colloc/test-colloc -a org.apache.mahout.vectorizer.DefaultAnalyzer -ng 3 -p
Just check out the output folder,the files u need is over there !!! (in sequence file format)
/bin/mahout seqdumper -s /home/developer/Desktop/colloc/test-colloc/ngrams/part-r-00000 >> out.txt will give u a text output !!!
Before I dive into ANTLR (because it is apparently not for the faint of heart), I just want to make sure I have made the right decision regarding its usage.
I want to create a grammar that will parse in a text file with predefined tags so that I can populate values within my application. (The text file is generated by another application.) So, essentially, I want to be able to parse something like this:
Name: TheFileName
Values: 5 3 1 6 1 3
Other Values: 5 3 1 5 1
In my application, TheFileName is stored as a String, and both sets of values are stored to an array. (This is just a sample, the file is much more complicated.) Anyway, am I at least going down the right path with ANTLR? Any other suggestions?
Edit
The files are created by the user and they define the areas via tags. So, it might look something like this.
Name: <string>TheFileName</string>
Values: <array>5 3 1 6 1 3</array>
Important Value: <double>3.45</double>
Something along those lines.
The basic question is how is the file more complicated? Is it basically more of the same, with a tag, a colon and one or more values, or is the basic structure of the other lines more complex? If it's basically just more of the same, code to recognize and read the data is pretty trivial, and a parser generator isn't likely to gain much. If the other lines have substantially different structure, it'll depend primarily on how they differ.
Edit: Based on what you've added, I'd go one (tiny) step further, and format your file as XML. You can then use existing XML parsers (and such) to read the files, extract data, verify that they fit a specified format, etc.
It depends on what control you have over the format of the file you are parsing. If you have no control then a parser-generator such as ANTLR may be valuable. (We do this ourselves for FORTRAN output files over which we have no control). It's quite a bit of work but we have now mastered the basic ANTLR lexer/parser strategy and it's starting to work well.
If, however, you have some or complete control over the format then create it with as much markup as necessary. I would always create such a file in XML as there are so many tools for processing it (not only the parsing, but also XPath, databases, etc.) In general we use ANTLR to parse semi-structured information into XML.
If you don't need for the format to be custom-built, then you should look into using an existing format such as JSON or XML, for which there are parsers available.
Even if you do need a custom format, you may be better off designing one that is dirt simple so that you don't need a full-blown grammar to parse it. Designing your own scripting grammar from scratch and doing a good job of it is a lot of work.
Writing grammar parsers can also be really fun, so if you're curious then you should go for it. But I don't recommend carelessly mixing learning exercises with practical work code.
Well, if it's "much more complicated", then, yes, a parser generator would be helpful. But, since you don't show the actual format of your file, how could anybody know what might be the right tool for the job?
I use the free GOLD Parser Builder, which is incredibly easy to use, and can generate the parser itself in many different languages. There are samples for parsing such expressions also.
If the format of the file is up to the user can you even define a grammar for it?
Seems like you just want a lexer at best. Using ANTLR just for the lexer part is possible, but would seem like overkill.
Are there any conventions for formatting console output from a command line app for readability and consistency? For instance, do you indent sub-information, when do you print a blank line, if ever, how should you accent important statements.
I've found output can quickly degenerate into a chaotic blur. I'm interested in hearing about what other people do.
Update: Really this is for embedded software which spits debug status out a terminal, but it's pretty much like a console app, and I figured everyone would be more familiar with that. Thanks so far.
I'd differentiate two kinds of programs:
Do you print information that might be used by a script (i.e. it should be parseable)? Then define a pretty strict format and use only that (for example fixed field separators).
Do you print information that need not be parsed by a script (or is there an alternative script-parseable format already)? Then write what comes natural:
My suggestions:
write it so that you would like to read it
indent sub-information 2 or 4 spaces, definitely not more
separate blocks of information by one empty line at most
respect the COLUMN environment variable (and possible ROWS if it applies to your output).
If this is for a *nix environment, then I'd recommend reading Basics of Unix Philosophy. It's not specific to output but there are some good guidelines for command line programs in general.
Expect the output of every program to become the input to another, as yet unknown, program. Don't clutter output with extraneous information. Avoid stringently columnar or binary input formats. Don't insist on interactive input.