Add Sklearn API for Gensim models (piskvorky#1462)

* created sklearn wrapper for Doc2Vec

* PEP8 fix

* added 'transform' function and refactored code

* updated d2v skl api code

* added unittests for sklearn api for d2v model

* fixed flake8 errors

* added skl api class for Text2Bow model

* updated docstring for d2vmodel api

* updated text2bow skl api code

* added unittests for text2bow skl api class

* updated 'testPipeline' and 'testTransform' for text2bow

* added 'tokenizer' param to text2bow skl api

* updated unittests for text2bow

* removed get_params and set_params functions from existing classes

* added tfidf api class

* added unittests for tfidf api class

* flake8 fixes

* added skl api for hdpmodel

* added unittests for hdp model api class

* flake8 fixes

* updated hdp api class

* added 'testPartialFit' and 'testPipeline' tests for hdp api class

* flake8 fixes

* added skl API class for phrases

* added unit tests for phrases API class

* flake8 fixes

* added 'testPartialFit' function for 'TestPhrasesTransformer'

* updated 'testPipeline' function for 'TestText2BowTransformer'

* updated code for transform function for HDP transformer

* updated tests as discussed in PR 1473

* added examples for new models in ipynb

* unpinned sklearn version for running unit-tests

* updated 'Pipeline' initialization format

* updated 'Pipeline' initialization format in ipynb

Author: chinmayapancholi13

docs/notebooks/sklearn_api.ipynb

@@ -17,3 +17,8 @@
 from .ldaseqmodel import LdaSeqTransformer  # noqa: F401
 from .w2vmodel import W2VTransformer  # noqa: F401
 from .atmodel import AuthorTopicTransformer  # noqa: F401
+from .d2vmodel import D2VTransformer  # noqa: F401
+from .text2bow import Text2BowTransformer  # noqa: F401
+from .tfidf import TfIdfTransformer  # noqa: F401
+from .hdp import HdpTransformer  # noqa: F401
+from .phrases import PhrasesTransformer  # noqa: F401

gensim/sklearn_api/__init__.py

@@ -0,0 +1,97 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2011 Radim Rehurek <radimrehurek@seznam.cz>
+# Licensed under the GNU LGPL v2.1 - http://www.gnu.org/licenses/lgpl.html
+
+"""
+Scikit learn interface for gensim for easy use of gensim with scikit-learn
+Follows scikit-learn API conventions
+"""
+
+import numpy as np
+from six import string_types
+from sklearn.base import TransformerMixin, BaseEstimator
+from sklearn.exceptions import NotFittedError
+
+from gensim import models
+
+
+class D2VTransformer(TransformerMixin, BaseEstimator):
+    """
+    Base Doc2Vec module
+    """
+
+    def __init__(self, dm_mean=None, dm=1, dbow_words=0, dm_concat=0,
+                dm_tag_count=1, docvecs=None, docvecs_mapfile=None,
+                comment=None, trim_rule=None, size=100, alpha=0.025,
+                window=5, min_count=5, max_vocab_size=None, sample=1e-3,
+                seed=1, workers=3, min_alpha=0.0001, hs=0, negative=5,
+                cbow_mean=1, hashfxn=hash, iter=5, sorted_vocab=1,
+                batch_words=10000):
+        """
+        Sklearn api for Doc2Vec model. See gensim.models.Doc2Vec and gensim.models.Word2Vec for parameter details.
+        """
+        self.gensim_model = None
+        self.dm_mean = dm_mean
+        self.dm = dm
+        self.dbow_words = dbow_words
+        self.dm_concat = dm_concat
+        self.dm_tag_count = dm_tag_count
+        self.docvecs = docvecs
+        self.docvecs_mapfile = docvecs_mapfile
+        self.comment = comment
+        self.trim_rule = trim_rule
+
+        # attributes associated with gensim.models.Word2Vec
+        self.size = size
+        self.alpha = alpha
+        self.window = window
+        self.min_count = min_count
+        self.max_vocab_size = max_vocab_size
+        self.sample = sample
+        self.seed = seed
+        self.workers = workers
+        self.min_alpha = min_alpha
+        self.hs = hs
+        self.negative = negative
+        self.cbow_mean = int(cbow_mean)
+        self.hashfxn = hashfxn
+        self.iter = iter
+        self.sorted_vocab = sorted_vocab
+        self.batch_words = batch_words
+
+    def fit(self, X, y=None):
+        """
+        Fit the model according to the given training data.
+        Calls gensim.models.Doc2Vec
+        """
+        self.gensim_model = models.Doc2Vec(documents=X, dm_mean=self.dm_mean, dm=self.dm,
+            dbow_words=self.dbow_words, dm_concat=self.dm_concat, dm_tag_count=self.dm_tag_count,
+            docvecs=self.docvecs, docvecs_mapfile=self.docvecs_mapfile, comment=self.comment,
+            trim_rule=self.trim_rule, size=self.size, alpha=self.alpha, window=self.window,
+            min_count=self.min_count, max_vocab_size=self.max_vocab_size, sample=self.sample,
+            seed=self.seed, workers=self.workers, min_alpha=self.min_alpha, hs=self.hs,
+            negative=self.negative, cbow_mean=self.cbow_mean, hashfxn=self.hashfxn,
+            iter=self.iter, sorted_vocab=self.sorted_vocab, batch_words=self.batch_words)
+        return self
+
+    def transform(self, docs):
+        """
+        Return the vector representations for the input documents.
+        The input `docs` should be a list of lists like : [ ['calculus', 'mathematical'], ['geometry', 'operations', 'curves'] ]
+        or a single document like : ['calculus', 'mathematical']
+        """
+        if self.gensim_model is None:
+            raise NotFittedError("This model has not been fitted yet. Call 'fit' with appropriate arguments before using this method.")
+
+        # The input as array of array
+        check = lambda x: [x] if isinstance(x[0], string_types) else x
+        docs = check(docs)
+        X = [[] for _ in range(0, len(docs))]
+
+        for k, v in enumerate(docs):
+            doc_vec = self.gensim_model.infer_vector(v)
+            X[k] = doc_vec
+
+        return np.reshape(np.array(X), (len(docs), self.gensim_model.vector_size))

gensim/sklearn_api/d2vmodel.py

@@ -0,0 +1,108 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2011 Radim Rehurek <radimrehurek@seznam.cz>
+# Licensed under the GNU LGPL v2.1 - http://www.gnu.org/licenses/lgpl.html
+
+"""
+Scikit learn interface for gensim for easy use of gensim with scikit-learn
+Follows scikit-learn API conventions
+"""
+
+import numpy as np
+from scipy import sparse
+from sklearn.base import TransformerMixin, BaseEstimator
+from sklearn.exceptions import NotFittedError
+
+from gensim import models
+from gensim import matutils
+
+
+class HdpTransformer(TransformerMixin, BaseEstimator):
+    """
+    Base HDP module
+    """
+
+    def __init__(self, id2word, max_chunks=None, max_time=None,
+            chunksize=256, kappa=1.0, tau=64.0, K=15, T=150, alpha=1,
+            gamma=1, eta=0.01, scale=1.0, var_converge=0.0001,
+            outputdir=None, random_state=None):
+        """
+        Sklearn api for HDP model. See gensim.models.HdpModel for parameter details.
+        """
+        self.gensim_model = None
+        self.id2word = id2word
+        self.max_chunks = max_chunks
+        self.max_time = max_time
+        self.chunksize = chunksize
+        self.kappa = kappa
+        self.tau = tau
+        self.K = K
+        self.T = T
+        self.alpha = alpha
+        self.gamma = gamma
+        self.eta = eta
+        self.scale = scale
+        self.var_converge = var_converge
+        self.outputdir = outputdir
+        self.random_state = random_state
+
+    def fit(self, X, y=None):
+        """
+        Fit the model according to the given training data.
+        Calls gensim.models.HdpModel
+        """
+        if sparse.issparse(X):
+            corpus = matutils.Sparse2Corpus(X)
+        else:
+            corpus = X
+
+        self.gensim_model = models.HdpModel(corpus=corpus, id2word=self.id2word, max_chunks=self.max_chunks,
+            max_time=self.max_time, chunksize=self.chunksize, kappa=self.kappa, tau=self.tau,
+            K=self.K, T=self.T, alpha=self.alpha, gamma=self.gamma, eta=self.eta, scale=self.scale,
+            var_converge=self.var_converge, outputdir=self.outputdir, random_state=self.random_state)
+        return self
+
+    def transform(self, docs):
+        """
+        Takes a list of documents as input ('docs').
+        Returns a matrix of topic distribution for the given document bow, where a_ij
+        indicates (topic_i, topic_probability_j).
+        The input `docs` should be in BOW format and can be a list of documents like : [ [(4, 1), (7, 1)], [(9, 1), (13, 1)], [(2, 1), (6, 1)] ]
+        or a single document like : [(4, 1), (7, 1)]
+        """
+        if self.gensim_model is None:
+            raise NotFittedError("This model has not been fitted yet. Call 'fit' with appropriate arguments before using this method.")
+
+        # The input as array of array
+        check = lambda x: [x] if isinstance(x[0], tuple) else x
+        docs = check(docs)
+        X = [[] for _ in range(0, len(docs))]
+
+        max_num_topics = 0
+        for k, v in enumerate(docs):
+            X[k] = self.gensim_model[v]
+            max_num_topics = max(max_num_topics, max(list(map(lambda x: x[0], X[k]))) + 1)
+
+        for k, v in enumerate(X):
+            # returning dense representation for compatibility with sklearn but we should go back to sparse representation in the future
+            dense_vec = matutils.sparse2full(v, max_num_topics)
+            X[k] = dense_vec
+
+        return np.reshape(np.array(X), (len(docs), max_num_topics))
+
+    def partial_fit(self, X):
+        """
+        Train model over X.
+        """
+        if sparse.issparse(X):
+            X = matutils.Sparse2Corpus(X)
+
+        if self.gensim_model is None:
+            self.gensim_model = models.HdpModel(id2word=self.id2word, max_chunks=self.max_chunks,
+                max_time=self.max_time, chunksize=self.chunksize, kappa=self.kappa, tau=self.tau,
+                K=self.K, T=self.T, alpha=self.alpha, gamma=self.gamma, eta=self.eta, scale=self.scale,
+                var_converge=self.var_converge, outputdir=self.outputdir, random_state=self.random_state)
+
+        self.gensim_model.update(corpus=X)
+        return self

gensim/sklearn_api/hdp.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2011 Radim Rehurek <radimrehurek@seznam.cz>
+# Licensed under the GNU LGPL v2.1 - http://www.gnu.org/licenses/lgpl.html
+
+"""
+Scikit learn interface for gensim for easy use of gensim with scikit-learn
+Follows scikit-learn API conventions
+"""
+
+from six import string_types
+from sklearn.base import TransformerMixin, BaseEstimator
+from sklearn.exceptions import NotFittedError
+
+from gensim import models
+
+
+class PhrasesTransformer(TransformerMixin, BaseEstimator):
+    """
+    Base Phrases module
+    """
+
+    def __init__(self, min_count=5, threshold=10.0, max_vocab_size=40000000,
+            delimiter=b'_', progress_per=10000):
+        """
+        Sklearn wrapper for Phrases model.
+        """
+        self.gensim_model = None
+        self.min_count = min_count
+        self.threshold = threshold
+        self.max_vocab_size = max_vocab_size
+        self.delimiter = delimiter
+        self.progress_per = progress_per
+
+    def fit(self, X, y=None):
+        """
+        Fit the model according to the given training data.
+        """
+        self.gensim_model = models.Phrases(sentences=X, min_count=self.min_count, threshold=self.threshold,
+            max_vocab_size=self.max_vocab_size, delimiter=self.delimiter, progress_per=self.progress_per)
+        return self
+
+    def transform(self, docs):
+        """
+        Return the input documents to return phrase tokens.
+        """
+        if self.gensim_model is None:
+            raise NotFittedError("This model has not been fitted yet. Call 'fit' with appropriate arguments before using this method.")
+
+        # input as python lists
+        check = lambda x: [x] if isinstance(x[0], string_types) else x
+        docs = check(docs)
+        X = [[] for _ in range(0, len(docs))]
+
+        for k, v in enumerate(docs):
+            phrase_tokens = self.gensim_model[v]
+            X[k] = phrase_tokens
+
+        return X
+
+    def partial_fit(self, X):
+        if self.gensim_model is None:
+            self.gensim_model = models.Phrases(sentences=X, min_count=self.min_count, threshold=self.threshold,
+                max_vocab_size=self.max_vocab_size, delimiter=self.delimiter, progress_per=self.progress_per)
+
+        self.gensim_model.add_vocab(X)
+        return self

gensim/sklearn_api/phrases.py

@@ -0,0 +1,66 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2011 Radim Rehurek <radimrehurek@seznam.cz>
+# Licensed under the GNU LGPL v2.1 - http://www.gnu.org/licenses/lgpl.html
+
+"""
+Scikit learn interface for gensim for easy use of gensim with scikit-learn
+Follows scikit-learn API conventions
+"""
+
+from six import string_types
+from sklearn.base import TransformerMixin, BaseEstimator
+from sklearn.exceptions import NotFittedError
+
+from gensim.corpora import Dictionary
+from gensim.utils import tokenize
+
+
+class Text2BowTransformer(TransformerMixin, BaseEstimator):
+    """
+    Base Text2Bow module
+    """
+
+    def __init__(self, prune_at=2000000, tokenizer=tokenize):
+        """
+        Sklearn wrapper for Text2Bow model.
+        """
+        self.gensim_model = None
+        self.prune_at = prune_at
+        self.tokenizer = tokenizer
+
+    def fit(self, X, y=None):
+        """
+        Fit the model according to the given training data.
+        """
+        tokenized_docs = list(map(lambda x: list(self.tokenizer(x)), X))
+        self.gensim_model = Dictionary(documents=tokenized_docs, prune_at=self.prune_at)
+        return self
+
+    def transform(self, docs):
+        """
+        Return the BOW format for the input documents.
+        """
+        if self.gensim_model is None:
+            raise NotFittedError("This model has not been fitted yet. Call 'fit' with appropriate arguments before using this method.")
+
+        # input as python lists
+        check = lambda x: [x] if isinstance(x, string_types) else x
+        docs = check(docs)
+        tokenized_docs = list(map(lambda x: list(self.tokenizer(x)), docs))
+        X = [[] for _ in range(0, len(tokenized_docs))]
+
+        for k, v in enumerate(tokenized_docs):
+            bow_val = self.gensim_model.doc2bow(v)
+            X[k] = bow_val
+
+        return X
+
+    def partial_fit(self, X):
+        if self.gensim_model is None:
+            self.gensim_model = Dictionary(prune_at=self.prune_at)
+
+        tokenized_docs = list(map(lambda x: list(self.tokenizer(x)), X))
+        self.gensim_model.add_documents(tokenized_docs)
+        return self