=====Getting Statistical Data Out of Your Simulation=====

You have a simulation up and running, but how do you get the statistical data you need ouput to a file? Below you will find some code provided by Professor Ackley that will allow you to do so.

There are two files that need to be modified:
   1. /src/drivers/mfmc/src/main.cpp
   2. /src/sim/include/AbstractDriver.h

====main.cpp====
To edit the main.cpp file, paste the following code into the **Private** section of the file:

<code cpp>
const char* GetSimDirPathTemporary(const char* format, ...) const
{
  static OverflowableCharBufferByteSink<500> buf;
  buf.Reset();
  buf.Printf("%s",this->GetSimulationBasePath());
  va_list ap;
  va_start(ap, format);
  buf.Vprintf(format, ap);
  if (buf.HasOverflowed())
  {
     FAIL(OUT_OF_ROOM);
  }
  return buf.GetZString();
}
</code>
and
<code cpp>
typedef typename CC::PARAM_CONFIG P;
typedef typename CC::ATOM_TYPE T;
</code>

Then paste the following in the **public** section of main.cpp:
<code cpp>
virtual void DoEpochEvents(Grid<GC>& grid, u32 epochs, u32 epochAEPS)
{
  u32 H = Grid<GC>::GetHeight();
  u32 W = Grid<GC>::GetWidth();

  u32 emptyCount = 0;
  for (u32 y = 0; y < H; ++y)
  {
    for (u32 x = 0; x < W; ++x)
    {
      Tile<CC> & tile = grid.GetTile(SPoint(x,y));
       for (u32 x = 0; x < P::TILE_WIDTH; ++x)
      {
        for (u32 y = 0; y < P::TILE_WIDTH; ++y)
        {
          const SPoint pt(x, y);
          if(Tile<CC>::IsInCache(pt))
          {
            continue;
          }
          const T * atom = tile.GetAtom(x,y);
          
          //<<<TODO>>> This is where you grab the data from your element. Modify accordingly.
          if (atom->GetType() == Element_Empty<CC>::THE_INSTANCE.GetType())
            ++emptyCount;
        }
      }
    }
  }
  
  //<<<TODO>>> replace FILE_NAME with the file name of your choice
  const char* path = GetSimDirPathTemporary("tbd/FILE_NAME.dat");
  FILE* fp = fopen(path, "a");
  
  //<<<TODO>>> This is where you output the specific data you need. Modify accordingly.
  fprintf(fp, "%d %d %d\n",epochs, epochAEPS, emptyCount);
  fclose(fp);
  // Remember to let the parent run too!
  Super::DoEpochEvents(grid, epochs, epochAEPS);
}
</code>

Please note: There are 3 TODO tags in the above snippet. These are where you'll need to modify the code to suit your needs.

====AbstractDriver.h====
Now we need to do a small modifcation to the AbstractDriver.h file. Paste the following code into the **public** section:
<code cpp>
const char * GetSimulationBasePath() const
{
  return &m_simDirBasePath[0];
}
</code>

And that's it! Happy scienceing.