public static Tuple <Array <Real>, Array <int> > NewDownSample_MaxPooling2d(Array <Real> arr, int pool_h, int pool_w, bool ignoreBorder = true)
{
int x_h = arr.Shape[0];
int x_w = arr.Shape[1];
int out_h = x_h / pool_h;
int out_w = x_w / pool_w;
if (ignoreBorder == false)
{
if (((x_h ^ pool_h) >= 0) && (x_h % pool_h != 0))
{
out_h++;
}
if (((x_w ^ pool_w) >= 0) && (x_w % pool_w != 0))
{
out_w++;
}
}
int arr_y_max = 0;
int arr_x_max = 0;
var poolout = NN.Array(new Real[out_h, out_w]);
var switches = NN.Array(new int[out_h, out_w, 2]);
for (int y_out = 0; y_out < out_h; y_out++)
{
int y = y_out * pool_h;
int y_min = y;
int y_max = Math.Min(y + pool_h, x_h);
for (int x_out = 0; x_out < out_w; x_out++)
{
int x = x_out * pool_w;
int x_min = x;
int x_max = Math.Min(x + pool_w, x_w);
var value = Real.NegativeInfinity;
for (int arr_y = y_min; arr_y < y_max; arr_y++)
{
for (int arr_x = x_min; arr_x < x_max; arr_x++)
{
var new_value = arr.Item[arr_y, arr_x];
if (new_value > value)
{
value = new_value;
arr_y_max = arr_y;
arr_x_max = arr_x;
}
}
}
switches[y_out, x_out, 0] = arr_y_max;
switches[y_out, x_out, 1] = arr_x_max;
poolout[y_out, x_out] = value;
}
}
return(Tuple.Create(poolout, switches));
}
public static Array <Real> new_Unpooling(Array <Real> delta, Array <int> switches, int pool_h, int pool_w, bool ignoreBorder = true)
{
var sh = new int[2];
var unpooled = NN.Array(new Real[switches.Shape[0] * pool_h, switches.Shape[1] * pool_w]);
for (int y = 0; y < delta.Shape[0]; y++)
{
for (int x = 0; x < delta.Shape[1]; x++)
{
unpooled[(int)switches[y, x, 0], (int)switches[y, x, 1]] = (Real)delta[y, x];
}
}
return(unpooled);
}
