src/integral.cpp
void gaussian_chain_second_derivative(gaussian_chain * dest, gaussian_chain * src, int key)
{
    gaussian_chain * temp1, * temp2, * temp3;

    temp1 = dest;
    temp2 = src;
    temp3 = gaussian_chain_calloc();
    
    gaussian_chain_derivative(temp3,temp2,key);
    gaussian_chain_derivative(temp1,temp3,key);

    gaussian_chain_free(temp3);
}
// obtain the second derivative of a gaussian function chain and store as another gaussian function chain over certain axis.
obtain the second derivative of a gaussian function chain and store as another gaussian function chain over certain axis.
obtain the second derivative of a gaussian function chain and store as another gaussian function chain over certain axis .
void gaussian_chain_second_derivative(gaussian_chain * dest, gaussian_chain * src, int key)
{
    gaussian_chain * temp1, * temp2, * temp3;
    temp1 = dest;
    temp2 = src;
    temp3 = gaussian_chain_calloc();
    gaussian_chain_derivative(temp3,temp2,key);
    gaussian_chain_derivative(temp1,temp3,key);
    gaussian_chain_free(temp3);
}
void gaussian_chain_second_derivative ( gaussian_chain * dest , gaussian_chain * src , int key ) { gaussian_chain * temp1 , * temp2 , * temp3 ; temp1 = dest ; temp2 = src ; temp3 = gaussian_chain_calloc ( ) ; gaussian_chain_derivative ( temp3 , temp2 , key ) ; gaussian_chain_derivative ( temp1 , temp3 , key ) ; gaussian_chain_free ( temp3 ) ; }
obtain the second derivative of a gaussian function chain and store as another gaussian function chain over certain axis.
obtain the second derivative of a gaussian function chain and store as another gaussian function chain over certain axis .