如何用列表对应的列表列表中替换数字?

时间:2017-12-11 20:38:57

标签: python list dictionary

我想知道如何使用字典对应方替换列表列表中的数字的正确方法。

目前我的代码是:

#the object list and max weight are supposed to be user input but i have hard coded it in for now to try and get other parts working first.

object_list = [(2, 70), (3, 85), (5, 120)] # the first number in the tuple is my weight and the second is my cost

max_weight = 17 #this is the number each list in the list of lists add to 

#seperatng weights and costs into a string then making a dictionary out of it.
weight_values = [int(i[0]) for i in object_list] 
cost_values = [int(i[1]) for i in object_list]
dictionary = dict(zip(weight_values, cost_values))

假设我有列表(增加最大权重的所有可能组合):

[[3, 2, 2, 2, 2, 2, 2, 2], [3, 3, 3, 2, 2, 2, 2], [3, 3, 3, 3, 3, 2], [5, 2, 2, 2, 2, 2, 2], [5, 3, 3, 2, 2, 2], [5, 3, 3, 3, 3], [5, 5, 3, 2, 2], [5, 5, 5, 2]]

我生成的字典是:

dictionary = {2: 70, 3: 85, 5: 120}

我想要尝试做的是将所有2个替换为70,将所有3个替换为85,将所有5个替换为120(对于这种情况)。生成的字典基于用户输入,因此在另一种情况下,所有2可能需要替换为35而不是70.我需要一种替换数字的方法,而不是特别说出如果有2的话将其替换为70.使用此答案(Recursive tree terminates function prematurely

生成此列表列表

2 个答案:

答案 0 :(得分:1)

替换列表中的值:

l = [[3, 2, 2, 2, 2, 2, 2, 2], [3, 3, 3, 2, 2, 2, 2], [3, 3, 3, 3, 3, 2], [5, 2, 2, 2, 2, 2, 2], [5, 3, 3, 2, 2, 2], [5, 3, 3, 3, 3], [5, 5, 3, 2, 2], [5, 5, 5, 2]]
dictionary = {2: 70, 3: 85, 5: 120}
new_l = [[dictionary[b] for b in i] for i in l]

输出:

[[85, 70, 70, 70, 70, 70, 70, 70], [85, 85, 85, 70, 70, 70, 70], [85, 85, 85, 85, 85, 70], [120, 70, 70, 70, 70, 70, 70], [120, 85, 85, 70, 70, 70], [120, 85, 85, 85, 85], [120, 120, 85, 70, 70], [120, 120, 120, 70]]

答案 1 :(得分:1)

替换值:

old_list = [[3, 2, 2, 2, 2, 2, 2, 2], [3, 3, 3, 2, 2, 2, 2], [3, 3, 3, 3, 3, 2], [5, 2, 2, 2, 2, 2, 2], [5, 3, 3, 2, 2, 2], [5, 3, 3, 3, 3], [5, 5, 3, 2, 2], [5, 5, 5, 2]]
dictionary = {2: 70, 3: 85, 5: 120}
new_list = []
temp = []
for i in old_list:
    temp = []
    for b in i:
        temp.append(dictionary[b])
    new_list.append(temp)

输出:

[[85, 70, 70, 70, 70, 70, 70, 70], [85, 85, 85, 70, 70, 70, 70], [85, 85, 85, 85, 85, 70], [120, 70, 70, 70, 70, 70, 70], [120, 85, 85, 70, 70, 70], [120, 85, 85, 85, 85], [120, 120, 85, 70, 70], [120, 120, 120, 70]]