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corpora.svmlightcorpus – Corpus in SVMlight format

Corpus in SVMlight format.

class gensim.corpora.svmlightcorpus.SvmLightCorpus(fname)

Corpus in SVMlight format.

Quoting http://svmlight.joachims.org/: The input file example_file contains the training examples. The first lines may contain comments and are ignored if they start with #. Each of the following lines represents one training example and is of the following format:

<line> .=. <target> <feature>:<value> <feature>:<value> ... <feature>:<value> # <info>
<target> .=. +1 | -1 | 0 | <float> 
<feature> .=. <integer> | "qid"
<value> .=. <float>
<info> .=. <string>

The “qid” feature (used for SVMlight ranking), if present, is ignored.

Although not mentioned in the specification above, SVMlight also expect its feature ids to be 1-based (counting starts at 1). We convert features to 0-base internally by decrementing all ids when loading a SVMlight input file, and increment them again when saving as SVMlight.

Initialize the corpus from a file.

classmethod load(fname)
Load a previously saved object from file (also see save).
save(fname)
Save the object to file via pickling (also see load).
static saveCorpus(fname, corpus, id2word=None)

Save a corpus in the SVMlight format.

The SVMlight <target> class tag is set to 0 for all documents.