removed all unnecessary calls to compute()

.gitignore

@@ -122,5 +122,3 @@ docs/source/auto_examples/
 docs/source/examples/mydask.png
 
 dask-worker-space
-/.project
-/.pydevproject

dask_ml/feature_extraction/text.py

@@ -120,6 +120,18 @@ def _hasher(self):
         return sklearn.feature_extraction.text.FeatureHasher
 
 
+def _n_samples(X):
+    """Count the number of samples in dask.array.Array X."""
+    def chunk_n_samples(chunk, axis, keepdims):
+        return np.array([chunk.shape[0]], dtype=np.int64)
+
+    return da.reduction(X,
+                        chunk=chunk_n_samples,
+                        aggregate=np.sum,
+                        concatenate=False,
+                        dtype=np.int64)
+
+
 def _document_frequency(X, dtype):
     """Count the number of non-zero values for each feature in dask array X."""
     def chunk_doc_freq(chunk, axis, keepdims):
@@ -133,7 +145,7 @@ def chunk_doc_freq(chunk, axis, keepdims):
                         aggregate=np.sum,
                         axis=0,
                         concatenate=False,
-                        dtype=dtype).compute().astype(dtype)
+                        dtype=dtype)
 
 
 class CountVectorizer(sklearn.feature_extraction.text.CountVectorizer):
@@ -203,17 +215,19 @@ class CountVectorizer(sklearn.feature_extraction.text.CountVectorizer):
     ['and', 'document', 'first', 'is', 'one', 'second', 'the', 'third', 'this']
     """
 
-    def fit_transform(self, raw_documents, y=None):
+    def get_params(self):
         # Note that in general 'self' could refer to an instance of either this
         # class or a subclass of this class.  Hence it is possible that
         # self.get_params() could get unexpected parameters of an instance of a
         # subclass.  Such parameters need to be excluded here:
-        subclass_instance_params = self.get_params()
+        subclass_instance_params = super().get_params()
         excluded_keys = getattr(self, '_non_CountVectorizer_params', [])
-        params = {key: subclass_instance_params[key]
-                  for key in subclass_instance_params
-                  if key not in excluded_keys}
+        return {key: subclass_instance_params[key]
+                for key in subclass_instance_params
+                if key not in excluded_keys}
 
+    def fit_transform(self, raw_documents, y=None):
+        params = self.get_params()
         vocabulary = params.pop("vocabulary")
         vocabulary_for_transform = vocabulary
 
@@ -227,12 +241,12 @@ def fit_transform(self, raw_documents, y=None):
             # Case 2: learn vocabulary from the data.
             vocabularies = raw_documents.map_partitions(_build_vocabulary, params)
             vocabulary = vocabulary_for_transform = (
-                _merge_vocabulary( *vocabularies.to_delayed() ))
+                _merge_vocabulary(*vocabularies.to_delayed()))
             vocabulary_for_transform = vocabulary_for_transform.persist()
             vocabulary_ = vocabulary.compute()
             n_features = len(vocabulary_)
 
-        meta = scipy.sparse.eye(0, format="csr", dtype=self.dtype)
+        meta = scipy.sparse.csr_matrix((0, n_features), dtype=self.dtype)
         if isinstance(raw_documents, dd.Series):
             result = raw_documents.map_partitions(
                 _count_vectorizer_transform, vocabulary_for_transform,
@@ -241,23 +255,14 @@ def fit_transform(self, raw_documents, y=None):
             result = raw_documents.map_partitions(
                 _count_vectorizer_transform, vocabulary_for_transform, params)
             result = build_array(result, n_features, meta)
-        result.compute_chunk_sizes()
 
         self.vocabulary_ = vocabulary_
         self.fixed_vocabulary_ = fixed_vocabulary
 
         return result
 
     def transform(self, raw_documents):
-        # Note that in general 'self' could refer to an instance of either this
-        # class or a subclass of this class.  Hence it is possible that
-        # self.get_params() could get unexpected parameters of an instance of a
-        # subclass.  Such parameters need to be excluded here:
-        subclass_instance_params = self.get_params()
-        excluded_keys = getattr(self, '_non_CountVectorizer_params', [])
-        params = {key: subclass_instance_params[key]
-                  for key in subclass_instance_params
-                  if key not in excluded_keys}
+        params = self.get_params()
         vocabulary = params.pop("vocabulary")
 
         if vocabulary is None:
@@ -271,14 +276,13 @@ def transform(self, raw_documents):
             except ValueError:
                 vocabulary_for_transform = dask.delayed(vocabulary)
             else:
-                (vocabulary_for_transform,) = client.scatter(
-                    (vocabulary,), broadcast=True
-                )
+                (vocabulary_for_transform,) = client.scatter((vocabulary,),
+                                                             broadcast=True)
         else:
             vocabulary_for_transform = vocabulary
 
         n_features = vocabulary_length(vocabulary_for_transform)
-        meta = scipy.sparse.eye(0, format="csr", dtype=self.dtype)
+        meta = scipy.sparse.csr_matrix((0, n_features), dtype=self.dtype)
         if isinstance(raw_documents, dd.Series):
             result = raw_documents.map_partitions(
                 _count_vectorizer_transform, vocabulary_for_transform,
@@ -287,7 +291,6 @@ def transform(self, raw_documents):
             transformed = raw_documents.map_partitions(
                 _count_vectorizer_transform, vocabulary_for_transform, params)
             result = build_array(transformed, n_features, meta)
-        result.compute_chunk_sizes()
         return result
 
 class TfidfTransformer(sklearn.feature_extraction.text.TfidfTransformer):
@@ -331,30 +334,23 @@ def fit(self, X, y=None):
         X : sparse matrix of shape n_samples, n_features)
             A matrix of term/token counts.
         """
-        # X = check_array(X, accept_sparse=('csr', 'csc'))
-        # if not sp.issparse(X):
-        #     X = sp.csr_matrix(X)
-        dtype = X.dtype if X.dtype in FLOAT_DTYPES else np.float64
-
-        if self.use_idf:
-            n_samples, n_features = X.shape
+        def get_idf_diag(X, dtype):
+            n_samples = _n_samples(X)   # X.shape[0] is not yet known
+            n_features = X.shape[1]
             df = _document_frequency(X, dtype)
-            # df = df.astype(dtype, **_astype_copy_false(df))
 
             # perform idf smoothing if required
             df += int(self.smooth_idf)
             n_samples += int(self.smooth_idf)
 
             # log+1 instead of log makes sure terms with zero idf don't get
             # suppressed entirely.
-            idf = np.log(n_samples / df) + 1
-            self._idf_diag = scipy.sparse.diags(
-                idf,
-                offsets=0,
-                shape=(n_features, n_features),
-                format="csr",
-                dtype=dtype,
-            )
+            return np.log(n_samples / df) + 1
+
+        dtype = X.dtype if X.dtype in FLOAT_DTYPES else np.float64
+
+        if self.use_idf:
+            self._idf_diag = get_idf_diag(X, dtype)
 
         return self
 
@@ -404,8 +400,17 @@ def _dot_idf_diag(chunk):
             # idf_ being a property, the automatic attributes detection
             # does not work as usual and we need to specify the attribute
             # name:
-            check_is_fitted(self, attributes=["idf_"], msg="idf vector is not fitted")
-
+            check_is_fitted(self, attributes=["idf_"],
+                            msg="idf vector is not fitted")
+            if dask.is_dask_collection(self._idf_diag):
+                _idf_diag = self._idf_diag.compute()
+                n_features = len(_idf_diag)
+                self._idf_diag = scipy.sparse.diags(
+                    _idf_diag,
+                    offsets=0,
+                    shape=(n_features, n_features),
+                    format="csr",
+                    dtype=_idf_diag.dtype)
             X = X.map_blocks(_dot_idf_diag, dtype=np.float64, meta=meta)
 
         if self.norm:
@@ -619,8 +624,7 @@ def fit(self, raw_documents, y=None):
         """
         self._check_params()
         self._warn_for_unused_params()
-        X = super().fit_transform(raw_documents,
-                                  y=self._non_CountVectorizer_params)
+        X = super().fit_transform(raw_documents)
         self._tfidf.fit(X)
         return self