Neural network in C-CodePudding

I have a trained neural network for classification problems in Matlab. I want to use the trained weight and apply it in C. My output of the neural network gives me a vector of 7 (output2[i]).

How can I use the same vec2ind function in Matlab which takes a matrix of vectors, each containing a single 1, and returns the indices of the ones, and stop as soon as it finds the 1?

I want to implement it in C languages.

I attached part of the code

Thank you

double sum = 0;
/// matrix multiplication
for (int i = 0; i < 29; i  )
{
        for (int k = 0; k < 2; k  )
        {
            sum  = inputs[k] * weights[i][k];
        }

        /// apply activation function
        output[i] = tanh_func(sum   biases[i]);
        sum = 0;
}

/// output layer
for (int i = 0; i < 7; i  )
{
    for (int k = 0; k < 29; k  )
    {
        sum  = output[k] * weights2[i][k];
    }

    /// apply activation function
    output2[i] = sigmoid(sum   biases2[i]);
    sum = 0;
}

CodePudding user response：

To get a better understanding you could use a triple pointer double*** tensor3d

initialize it with

tensor3d =  malloc( dim0 * sizeof( double** ));
for( int i = 0; i < dim0;   i )
{
  tensor3d[i] =  malloc( dim1 * sizeof( double* ));
  for( int j = 0; j < dim1;   j )
  {
    tensor3d[i][j] =  malloc( dim2 * sizeof( double ));
  }
}

if you have copied the matrix of vectors inside that 3dim-array you can do that

int indices[dim0][dim1];

for( int i = 0; i < dim0;   i )
{
  for( int j = 0; j < dim1;   j )
  {
    for( int k = 0; k < dim2;   k )
    {
      if( tensor3d[i][j][k] > 0.99 && tensor3d[i][j][k] < 1.01 )
      {
        indices[i][j] = k;
        break;
      }
    }
  }
}

but in real life you would use a 1 dim-array flattensor3d[] and

tensor3d[i][j][k] == flattensor3d[i * dim0 * dim1   j * dim1   k]

CodePudding user response：

For writing just vec2ind in C, see other answers.

Alternatively, if you have access to MATLAB Coder, that can convert MATLAB code (the entire algorithm) to C code automatically: https://www.mathworks.com/help/coder/index.html