使用列表推导式对具有有序编号的元素进行排序

如何解决使用列表推导式对具有有序编号的元素进行排序

所以我正在尝试在 python 中学习列表推导式，是否可以使用连续/有序数字对元素的值进行排序？给定以下数据，类似这样

basket = {
    "basket1": [
        {"type": "Fruit","name": "Melon"},{"type": "Goods","name": "Hershey Bar"},....
    ],"basket2": [
        {"type": "Fruit","name": "Watermelon"},"name": "mineral"},}

我目前的结果：

1. Fruit
1.1 Melon
1.3 Watermelon
2. Goods
2.2 Hershey Bar
2.4 mineral

和这样的预期结果：

1. Fruit
1.1 Melon
1.2 Watermelon
2. Goods
2.3 Hershey Bar
2.4 mineral
# and so on

我尝试过的尝试是这样的。

def object():
    data = basket["basket1"] + inventory["basket2"]

    # using list comprehensions
    fruits = [
        f"1.{i} {x['name']} \n" for i,x in enumerate(data,1) if x["type"] == "Fruit"
    ]
    goods = [
        f"2.{i} {x['name']} \n" for i,1) if x["type"] == "Goods"
    ]

    if fruits and goods:
        print("1. Fruit: " + to_string(fruits))
        print("2. Goods: " + to_string(goods))

非常感谢您的支持。

解决方法

在列表推导式中使用另一种列表推导式：

def object():
    data = basket["basket1"] + basket["basket2"]

    # using list comprehensions
    fruits = [
        f"1.{i} {x['name']} \n" for i,x in enumerate([d for d in data if d["type"] == "Fruit"],1)
    ]
    goods = [
        f"2.{i} {x['name']} \n" for i,x in enumerate([d for d in data if d["type"] == "Goods"],1)
    ]

    if fruits and goods:
        print("1. Fruit: " + to_string(fruits))
        print("2. Goods: " + to_string(goods))

更有效的方法是使用生成器表达式：

def object():
    data = basket["basket1"] + basket["basket2"]

    # using list comprehensions
    fruits = [
        f"1.{i} {x['name']} \n" for i,x in enumerate((d for d in data if d["type"] == "Fruit"),x in enumerate((d for d in data if d["type"] == "Goods"),1)
    ]

    if fruits and goods:
        print("1. Fruit: " + to_string(fruits))
        print("2. Goods: " + to_string(goods))

,

先排序然后在第二步重命名怎么样？

fruit = []
goods = []
for item in basket.values():
    for element in item:
        if element['type'] == 'Fruit':
            fruit.append(element['name'])
        elif element['type'] == 'Goods':
            goods.append(element['name'])
        else:
            pass

fruit = [f"1.{i} {x}" for i,x in enumerate(fruit,1)]
good = [f"2.{i} {x}" for i,x in enumerate(goods,len(fruit)+1)]

print("1. Fruit:\n" + '\n'.join(fruit))
print("2. Goods:\n" + '\n'.join(good))

>>>
1. Fruit:
1.1 Melon
1.2 Watermelon
2. Goods:
2.3 Hershey Bar
2.4 Mineral

,

您正在寻找数据的给定表示。 首先根据您的需要将您的数据以更实用的格式排列，然后根据所需的格式打印它们。

from collections import defaultdict

# a dictionary which elements are initialized as lists by default
data = defaultdict(list)

# group data by type (Good,Fruits,...)
for items in baskets.values():
    for item in items:
        data[item['type']].append(item['name'])
        
print(data)

defaultdict(<class 'list'>,{'Fruit': ['Melon','Watermelon'],'Goods': ['Hershey Bar','Mineral']})

# Print the data with the wanted format
for i,(k,v) in enumerate(data.items()):
    print(f"{i+1} {k}")
    for j,item in enumerate(v):
        print(f"{i+1}.{j+1} item")

1 Fruit
1.1 item
1.2 item
2 Goods
2.1 item
2.2 item

,

嗨，欢迎来到 python，你将度过一生的时光！
你可以问吗？答案是 99.9% 是。让我们看看如何：
首先让我们尝试改变我们提供答案的策略。
与其遍历整个篮子，不如先将它们排序到不同的列表中，然后枚举它们。

    def sort_it(baskets):
        aggregate = defaultdict(list)
        for _,items_list in basket.items():
            for item in items_list:
                aggregate[item["type"]].append(item["name"])

        for title,values,idx in enumerate(addregate.items(),1):
            print(f"{idx}. {title}: ")
            for item,num on enumerate(values):
                print("{idx}.{num} item")