Issue #298: Re-introduce rho relying on chunksize.

gensim/models/ldamodel.py

@@ -491,8 +491,6 @@ def update(self, corpus, chunksize=None, decay=None, offset=None,
 
         """
         # use parameters given in constructor, unless user explicitly overrode them
-        if chunksize is None:
-            chunksize = self.chunksize
         if decay is None:
             decay = self.decay
         if offset is None:
@@ -517,6 +515,9 @@ def update(self, corpus, chunksize=None, decay=None, offset=None,
             logger.warning("LdaModel.update() called with an empty corpus")
             return
 
+        if chunksize is None:
+            chunksize = min(lencorpus, self.chunksize)
+
         self.state.numdocs += lencorpus
 
         if update_every:
@@ -544,7 +545,7 @@ def update(self, corpus, chunksize=None, decay=None, offset=None,
         # pass_ + num_updates handles increasing the starting t for each pass,
         # while allowing it to "reset" on the first pass of each update
         def rho():
-            return pow(offset + ((pass_ + self.num_updates)), -decay)
+            return pow(offset + pass_ + (self.num_updates / chunksize), -decay)
 
         for pass_ in xrange(passes):
             if self.dispatcher:
@@ -628,7 +629,7 @@ def do_mstep(self, rho, other, extra_pass=False):
 
         if not extra_pass:
             # only update if this isn't an additional pass
-            self.num_updates += 1
+            self.num_updates += other.numdocs
 
     def bound(self, corpus, gamma=None, subsample_ratio=1.0):
         """