[mlpack-git] master, mlpack-1.0.x: Refactor to avoid holding variables in the class itself (reduces the size of SA a bit). Remove an unnecessary variable too. Minor changes, no public API changes. (a826c9b)

[gitdub at big.cc.gt.atl.ga.us]

Repository : https://github.com/mlpack/mlpack

On branches: master,mlpack-1.0.x
Link       : https://github.com/mlpack/mlpack/compare/904762495c039e345beba14c1142fd719b3bd50e...f94823c800ad6f7266995c700b1b630d5ffdcf40

>---------------------------------------------------------------

commit a826c9bd2bd4fbdc134151777e35bb75ca517308
Author: Ryan Curtin <ryan at ratml.org>
Date:   Wed Jul 2 21:15:05 2014 +0000

    Refactor to avoid holding variables in the class itself (reduces the size of SA a bit).  Remove an unnecessary variable too.  Minor changes, no public API changes.


>---------------------------------------------------------------

a826c9bd2bd4fbdc134151777e35bb75ca517308
 src/mlpack/core/optimizers/sa/sa.hpp      | 16 +++++++---------
 src/mlpack/core/optimizers/sa/sa_impl.hpp | 30 +++++++++++++++++-------------
 2 files changed, 24 insertions(+), 22 deletions(-)

diff --git a/src/mlpack/core/optimizers/sa/sa.hpp b/src/mlpack/core/optimizers/sa/sa.hpp
index 57e2734..7bbf7a5 100644
--- a/src/mlpack/core/optimizers/sa/sa.hpp
+++ b/src/mlpack/core/optimizers/sa/sa.hpp
@@ -170,15 +170,13 @@ class SA
   arma::mat moveSize;
 
 
-  // following variables are initialized inside Optimize
-  arma::mat accept;
-  double energy;
-  size_t idx;
-  size_t nVars;
-  size_t sweepCounter;
-
-  void GenerateMove(arma::mat& iterate);
-  void MoveControl(size_t nMoves);
+  void GenerateMove(arma::mat& iterate,
+                    arma::mat& accept,
+                    double& energy,
+                    size_t& idx,
+                    size_t& sweepCounter);
+
+  void MoveControl(size_t nMoves, arma::mat& accept);
 };
 
 }; // namespace optimization
diff --git a/src/mlpack/core/optimizers/sa/sa_impl.hpp b/src/mlpack/core/optimizers/sa/sa_impl.hpp
index fc2ac5c..b739943 100644
--- a/src/mlpack/core/optimizers/sa/sa_impl.hpp
+++ b/src/mlpack/core/optimizers/sa/sa_impl.hpp
@@ -45,7 +45,6 @@ SA<FunctionType, CoolingScheduleType>::SA(
   maxMove.fill(maxMoveCoef);
   moveSize.set_size(rows, cols);
   moveSize.fill(initMoveCoef);
-  accept.zeros(rows, cols);
 }
 
 //! Optimize the function (minimize).
@@ -60,24 +59,25 @@ double SA<FunctionType, CoolingScheduleType>::Optimize(arma::mat &iterate)
 
   size_t i;
   size_t frozenCount = 0;
-  energy = function.Evaluate(iterate);
+  double energy = function.Evaluate(iterate);
   size_t oldEnergy = energy;
   math::RandomSeed(std::time(NULL));
 
-  nVars = rows * cols;
-  idx = 0;
-  sweepCounter = 0;
+  size_t idx = 0;
+  size_t sweepCounter = 0;
+
+  arma::mat accept(rows, cols);
   accept.zeros();
 
   // Initial Moves to get rid of dependency of initial states.
   for (i = 0; i < initMoves; ++i)
-    GenerateMove(iterate);
+    GenerateMove(iterate, accept, energy, idx, sweepCounter);
 
   // Iterating and cooling.
   for (i = 0; i != maxIterations; ++i)
   {
     oldEnergy = energy;
-    GenerateMove(iterate);
+    GenerateMove(iterate, accept, energy, idx, sweepCounter);
     temperature = coolingSchedule.nextTemperature(temperature, energy);
 
     // Determine if the optimization has entered (or continues to be in) a
@@ -88,7 +88,7 @@ double SA<FunctionType, CoolingScheduleType>::Optimize(arma::mat &iterate)
       frozenCount = 0;
 
     // Terminate, if possible.
-    if (frozenCount >= maxToleranceSweep * nVars)
+    if (frozenCount >= maxToleranceSweep * iterate.n_elem)
     {
       Log::Debug << "SA: minimized within tolerance " << tolerance << " for "
           << maxToleranceSweep << " sweeps after " << i << " iterations; "
@@ -115,7 +115,11 @@ template<
     typename CoolingScheduleType
 >
 void SA<FunctionType, CoolingScheduleType>::GenerateMove(
-    arma::mat& iterate)
+    arma::mat& iterate,
+    arma::mat& accept,
+    double& energy,
+    size_t& idx,
+    size_t& sweepCounter)
 {
   double prevEnergy = energy;
   double prevValue = iterate(idx);
@@ -147,7 +151,7 @@ void SA<FunctionType, CoolingScheduleType>::GenerateMove(
   }
 
   ++idx;
-  if (idx == nVars) // Finished with a sweep.
+  if (idx == iterate.n_elem) // Finished with a sweep.
   {
     idx = 0;
     ++sweepCounter;
@@ -155,7 +159,7 @@ void SA<FunctionType, CoolingScheduleType>::GenerateMove(
 
   if (sweepCounter == moveCtrlSweep) // Do MoveControl().
   {
-    MoveControl(moveCtrlSweep);
+    MoveControl(moveCtrlSweep, accept);
     sweepCounter = 0;
   }
 }
@@ -179,7 +183,7 @@ template<
     typename CoolingScheduleType
 >
 void SA<FunctionType, CoolingScheduleType>::MoveControl(
-    size_t nMoves)
+    size_t nMoves, arma::mat& accept)
 {
   arma::mat target;
   target.copy_size(accept);
@@ -190,7 +194,7 @@ void SA<FunctionType, CoolingScheduleType>::MoveControl(
 
   // To avoid the use of element-wise arma::min(), which is only available in
   // Armadillo after v3.930, we use a for loop here instead.
-  for (size_t i = 0; i < nVars; ++i)
+  for (size_t i = 0; i < accept.n_elem; ++i)
     moveSize(i) = (moveSize(i) > maxMove(i)) ? maxMove(i) : moveSize(i);
 
   accept.zeros();