def get_class_predict(class_split, ratio):
    """get predict memory for each class

    :param class_split: use class split boundary to get class predict
    :param ratio: ratio for two adjacent class split boundary to generate
           the predict value. for example, class_split=[300, 800, 1500, 5000],
           ratio=0.5, then class_predict[0] = class_split[0]*0.5 +
           class_split[1]*0.5 and class_predict[-1] = class_split[-1], then
           class_predict = [550, 1150, 3250, 5000]
    """
    class_predict = []
    for i in range(len(class_split) - 1):
        class_predict.append(ratio*class_split[i] + (1-ratio)*class_split[i+1])
    class_predict.append(class_split[-1])
    return class_predict