def get_signed_connectome(matrix, method='negative'):
    """
    Function used to extract positive or negative values from matrix
    
    Parameters
    ----------
    matrix : 2D array, n x n
        Connectivity matrix in square form
    method : {'negative', 'positive'} | 'negative' default
        This is used to filter values in the connectomes.
    """
    
    sign = 1
    if method == 'negative':
        sign = -1
    
    mask_ = (matrix * sign) > 0
    signed_matrix = matrix * mask_
    
    return signed_matrix