带条件的字典嵌套列表

Question

I feel like i'm loosing my mind over this...

So I have added comments twice because i think i'm not really making sense. The code I have is more psuedocode because I have been going in circles.

The idea is to have a list of items that have a dictionary containing various prices, with various quantity's according to that price. Ideally I want to insert them in order of the name, then in order of the price

Here is what I have so far.

MyList = []
print(MyList)

def insertIntoList(listToAdd):
    """insert into MyList if name not in first element of each list
    if the name is in the list, check to see if the first element of
    any dictionary has the same value, if it does, add the last element
    to the last element of that dictionary element"""
    if len(MyList) == 0:
        MyList.append(listToAdd)

    for ind, i in enumerate(listToAdd):
        #for each list in listToAdd
        if i in MyList:
            #if name in MyList
            for item in listToAdd[1][0]:
                if item in MyList[ind] == listToAdd[1][0]:
                    #if the first element of each dictionary 
                    # in the list is equivalent to the first element
                    # of the dict, then increment the last element
                    MyList += listToAdd[1][1]
                else:
                    #otherwise add the new dictionary to the list
                    MyList.append(listToAdd[1])
        else:
            #otherwise if name isnt in MyList
            MyList.append(listToAdd)



insertIntoList(["Foo", [{1010:10101010}]])
insertIntoList(["Bar", [{0:1}]])
insertIntoList(["Bar", [{1:1}]])
insertIntoList(["Foo", [{1010:5}]])
print(MyList)

This should print;

[["Bar", [{0:1}, {1:1}]], ["Foo", [{1010:10101015}]]]

Answer 1

Perhaps you should use a better data structure like,

$ cat price.py
from collections import defaultdict

d = defaultdict(dict)

def insert(key, value):
    for k,v in value.items():
        d[key].setdefault(k, 0)
        d[key][k] += v

insert("Foo", {1010:10101010})
insert("Bar", {0:1})
insert("Bar", {1:1})
insert("Foo", {1010:5})
print(dict(d))
print([[key, [{k:v} for k,v in value.items()]] for key,value in d.items()])

Since, the data to be inserted is based on the key, a dict should be apt here. And you could shape it to be however you want in the end like,

Output:

$ python price.py
'Foo': {1010: 10101015}, 'Bar': {0: 1, 1: 1}}
[['Foo', [{1010: 10101015}]], ['Bar', [{0: 1}, {1: 1}]]]

Answer 2

You could do something like this

def insert(result, key, price, quantity):
    priceDict = result.get(key, {price: 0})
    priceDict[price] += quantity
    result[key] = priceDict
    return result

result = {}
print(result) # {}
insert(result, "Foo", 1010, 10101010)
insert(result, "Bar", 0, 1)
insert(result, "Foo", 1010, 5)
print(result) # {'Foo': {1010: 10101015}, 'Bar': {0: 1}}