Question

我想根据名称和顺序过滤列表数据。输出应如下所示：

过滤后，它应该给 'abc' 的名字，因为在每个有 'buy' 的字典中所有的订单都是 name = 'abc'。
不是 'xyz' 和 'dfg'，因为有些订单中包含 'sell'。

简而言之，我希望输出应该是在任何字典中都没有 'sell' 的名称例如。

{'name': 'abc', 'order':'Buy', 'quantity': 25252},{'name': 'abc', 'order':'Buy', 'quantity': 24424}, 和
{'name': 'abc', 'order':'Buy', 'quantity': 255252}

没有卖单，所以输出应该只有'abc'。

输入

data = [
    {'name': 'abc', 'order':'Buy', 'quantity': 25252},
    {'name': 'xyz', 'order':'Buy', 'quantity': 4444},
    {'name': 'dfg', 'order':'sell', 'quantity': 254242252},
    {'name': 'xyz', 'order':'sell', 'quantity': 25224252},
    {'name': 'abc', 'order':'Buy', 'quantity': 24424},
    {'name': 'dfg', 'order':'sell', 'quantity': 2424},
    {'name': 'abc', 'order':'Buy', 'quantity': 255252},
]

期望输出

'abc'

Answer 1

这是我能想到的最简单的方法

sell_list = []
res = []

# This loop will check for all the items that have order = sell
for i in data:
    if i['order'] == 'sell' and i['name'] not in sell_list:
        sell_list.append(i['name'])

for i in data:
    # Checking if the item has order = buy and check if it already have order = sell 
    if i['order'] == 'Buy' and i['name'] not in sell_list and i['name'] not in res:
        res.append(i['name'])


print(res)

Answer 2

如果 def download_file(url): # prefere with when exceptions are expected with open(url.split("=")[-1] + ".pdf", 'wb') as fp: delay = 5 max_retries = 3 for _ in range(max_retries): try: req = urlopen(url) CHUNK = 20480 chunk = req.read(CHUNK) fp.write(chunk) break # do not loop after a successfull download... except urllib.error.URLError: time.sleep(delay) delay *= 2 else: # signal an abort if download was not possible print(f"Failed for {url} after {max_retries} attempt") # or if you want to abort the script # raise Exception(f"Failed for {url} after {max_retries} attempt") 是您的列表，则：

data

打印：

sell_set = {d["name"] for d in data if d["order"] == "sell"}

print(
    *{
        d["name"]
        for d in data
        if d["order"] == "Buy" and not d["name"] in sell_set
    }
)

使用多个条件过滤字典列表

2 个答案: