Improve vector handling

spacy/vectors.pyx

@@ -18,6 +18,7 @@ cdef class Vectors:
     cdef readonly StringStore strings
     cdef public object key2row
     cdef public object keys
+    cdef public int i
 
     def __init__(self, strings, data_or_width):
         self.strings = StringStore()
@@ -26,13 +27,12 @@ cdef class Vectors:
                                            dtype='f')
         else:
             data = data_or_width
+        self.i = 0
         self.data = data
         self.key2row = {}
         self.keys = np.ndarray((self.data.shape[0],), dtype='uint64') 
-        for i, string in enumerate(strings):
+        for string in strings:
-            key = self.strings.add(string)
+            self.add_key(string)
-            self.key2row[key] = i
-            self.keys[i] = key
 
     def __reduce__(self):
         return (Vectors, (self.strings, self.data))
@@ -56,21 +56,29 @@ cdef class Vectors:
         yield from self.data
 
     def __len__(self):
-        # TODO: Fix the quadratic behaviour here!
+        return self.i
-        return max(self.key2row.values())
 
     def __contains__(self, key):
         if isinstance(key, basestring_):
             key = self.strings[key]
         return key in self.key2row
 
-    def add_key(self, string, vector=None):
+    def add(self, key, vector=None):
-        key = self.strings.add(string)
+        if isinstance(key, basestring_):
-        next_i = len(self) + 1
+            key = self.strings.add(key)
-        self.keys[next_i] = key
+        if key not in self.key2row:
-        self.key2row[key] = next_i
+            i = self.i
+            if i >= self.keys.shape[0]:
+                self.keys.resize((self.keys.shape[0]*2,))
+                self.data.resize((self.data.shape[0]*2, self.data.shape[1]))
+            self.key2row[key] = self.i
+            self.keys[self.i] = key
+            self.i += 1
+        else:
+            i = self.key2row[key]
         if vector is not None:
-            self.data[next_i] = vector
+            self.data[i] = vector
+        return i
 
     def items(self):
         for i, string in enumerate(self.strings):
@@ -139,5 +147,5 @@ cdef class Vectors:
             ('strings', lambda b: self.strings.from_bytes(b)),
             ('vectors', deserialize_weights)
         ))
-        util.from_bytes(deserializers, exclude)
+        util.from_bytes(data, deserializers, exclude)
         return self

spacy/vocab.pyx

@@ -246,11 +246,13 @@ cdef class Vocab:
     def vectors_length(self):
         return len(self.vectors)
 
-    def clear_vectors(self):
+    def clear_vectors(self, new_dim=None):
         """Drop the current vector table. Because all vectors must be the same
         width, you have to call this to change the size of the vectors.
         """
-        raise NotImplementedError
+        if new_dim is None:
+            new_dim = self.vectors.data.shape[1]
+        self.vectors = Vectors(self.strings, new_dim)
 
     def get_vector(self, orth):
         """Retrieve a vector for a word in the vocabulary.
@@ -278,7 +280,7 @@ cdef class Vocab:
         """
         if not isinstance(orth, basestring_):
             orth = self.strings[orth]
-        self.vectors.add_key(orth, vector=vector)
+        self.vectors.add(orth, vector=vector)
 
     def has_vector(self, orth):
         """Check whether a word has a vector. Returns False if no