def normalize_data(x_train, x_validate):
    """ Min-Max normalize the feature data.

    :param x_train: feature training data
    :param x_validate: feature validation data
    :return: x_train_norm, x_validate_norm
    """
    min_x = x_train.min(axis=0)
    max_x = x_train.max(axis=0)
    x_train = (x_train - min_x) / (max_x - min_x)
    x_validate = (x_validate - min_x) / (max_x - min_x)

    return x_train, x_validate