# HG changeset patch
# User James Bergstra <bergstrj@iro.umontreal.ca>
# Date 1284046362 14400
# Node ID baf1988db55728271435b0b47494ee43fe2be7b8
# Parent  bc3f7834db83042670503be377b9d033e809d0c1
v2planning optimization - added API

diff -r bc3f7834db83 -r baf1988db557 doc/v2_planning/optimization.txt
--- a/doc/v2_planning/optimization.txt	Wed Sep 08 20:45:17 2010 -0400
+++ b/doc/v2_planning/optimization.txt	Thu Sep 09 11:32:42 2010 -0400
@@ -39,3 +39,46 @@
 
 
 
+
+Proposal for API
+================
+
+Stick to the same style of API that we've used for SGD so far.  I think it has
+worked well.  It takes theano expressions as inputs and returns theano
+expressions as results.  The caller is responsible for building those
+expressions into a callable function that does the minimization (and other
+things too maybe).
+
+
+def stochastic_gradientbased_optimization_updates(parameters, cost=None, grads=None, **kwargs):
+   """
+   :param parameters: list or tuple of Theano variables (typically shared vars)
+       that we want to optimize iteratively algorithm.
+
+   :param cost: scalar-valued Theano variable that computes noisy estimate of
+       cost  (what are the conditions on the noise?).  The cost is ignored if
+       grads are given.
+
+   :param grads: list or tuple of Theano variables representing the gradients on
+       the corresponding parameters.  These default to tensor.grad(cost,
+       parameters).
+
+   :param kwargs: algorithm-dependent arguments
+
+   :returns: a list of pairs (v, new_v) that indicate the value (new_v) each
+      variable (v) should take in order to carry out the optimization procedure.
+
+      The first section of the return value list corresponds to the terms in
+      `parameters`, and the optimization algorithm can return additional update
+      expression afterward.  This list of pairs can be passed directly to the
+      dict() constructor to create a dictionary such that dct[v] == new_v.
+   """
+
+
+Why not a class interface with an __init__ that takes the kwargs, and an
+updates() that returns the updates?  It would be wrong for auxiliary shared
+variables to be involved in two updates, so the interface should not encourage
+separate methods for those two steps.
+
+
+