mishMatrix function

Tensor<Matrix> mishMatrix(Tensor<Matrix> m)

Implementation

Tensor<Matrix> mishMatrix(Tensor<Matrix> m) {
  int numRows = m.shape[0];
  int numCols = m.shape[1];
  Matrix mMat = m.value;
  Matrix outValue = [];

  for (int i = 0; i < numRows; i = i + 1) {
    Vector row = [];
    for (int j = 0; j < numCols; j = j + 1) {
      double x = mMat[i][j];
      double sp = log(1.0 + exp(x));
      double e2sp = exp(2.0 * sp);
      double t = e2sp.isInfinite ? 1.0 : (e2sp - 1.0) / (e2sp + 1.0);
      row.add(x * t);
    }
    outValue.add(row);
  }

  Tensor<Matrix> out = Tensor<Matrix>(outValue);

  out.creator = Node(
    [m],
        () {
      int length = m.data.length;
      for (int i = 0; i < length; i = i + 1) {
        double x = m.data[i];
        double sp = log(1.0 + exp(x));
        double e2sp = exp(2.0 * sp);
        double t = e2sp.isInfinite ? 1.0 : (e2sp - 1.0) / (e2sp + 1.0);
        double s = 1.0 / (1.0 + exp(-x));
        double grad = t + x * s * (1.0 - t * t);
        m.grad[i] = m.grad[i] + out.grad[i] * grad;
      }
    },
    opName: 'mish_matrix',
    cost: numRows * numCols * 3,
  );

  return out;
}