def computeFraction(feature_1, feature_2 ):
    """ 
        Parameters: 
            Two numeric feature vectors for which we want to compute a ratio
            between
     
        Output: 
            Return fraction or ratio of feature_1 divided by feature_2
    """
    
    fraction = 0.
    
    if feature_1 == "NaN":  
        fraction = 0.0
    elif feature_2 == "NaN":
        fraction = 0.0
    else: 
        fraction = int(feature_1) / float(feature_2)

    return fraction