我如何访问字典中的内容，列表中的内容，字典中的内容？

Question

How would I access the object 'c' in a print statement?

{'symbol': 'BTCUSD', 'totalResults': 1, 'results': [{'o': 41002.26, 'h': 43361, 'l': 40875.51, 'c': 42364.13, 'v': 59454.94294, 't': 1647993599999}]}

Overall code(API KEY REMOVED BUT ISNT THE ISSUE):

command = ""
while(command != "q"):
    command = input("Choose [c] for current price, [p] for previous days price, and [q] to quit.")
    if(command == "c"):
        coin = input("Enter currency pair: ")
        crypto_data = (requests.get(f'https://api.finage.co.uk/last/crypto/{coin}?apikey=API_KEY')).json()
        print(f"The current price of {coin} is {crypto_data['price']}")
    
    if(command == "p"):
        coin = input("Enter currency pair: ")
        crypto_data = (requests.get(f'https://api.finage.co.uk/agg/crypto/prev-close/{coin}?apikey=API_KEY')).json()
        *print(f"The previous price of {coin} is {crypto_data['results']['c']}")*

• being where I get the issue I get back a variety of codes, mostly I cant call a string and it must be a slice or integer

I have tried a range statement as well but it also brings back an error

TIA!

Answer 1

The same way you would do it if they were in a dictionary first, then an array, and then a dictionary again:

crypto_data = {'symbol': 'BTCUSD', 'totalResults': 1, 'results': [{'o': 41002.26, 'h': 43361, 'l': 40875.51, 'c': 42364.13, 'v': 59454.94294, 't': 1647993599999}]}

print(crypto_data["results"][0]["c"])

This is because:

# crypto_data is a dictionary, so you can access items by their key, i.e.
crypto_data["results"]
# which returns an array: [{'o': 41002.26, 'h': 43361, 'l': 40875.51, 'c': 42364.13, 'v': 59454.94294, 't': 1647993599999}]

# so then access items in the array by their index, i.e.
crypto_data["results"][0]
# which returns a dictionary: {'o': 41002.26, 'h': 43361, 'l': 40875.51, 'c': 42364.13, 'v': 59454.94294, 't': 1647993599999}

# so then access items in the dictionary by their key again, i.e.
crypto_data["results"][0]["c"]
# which returns an integer: 42364.13

Answer 2

if

myDict = {'symbol': 'BTCUSD', 'totalResults': 1, 'results': [{'o': 41002.26, 'h': 43361, 'l': 40875.51, 'c': 42364.13, 'v': 59454.94294, 't': 1647993599999}]}

then myDict["results"][0]["c"] would return 42364.1

Answer 3

It's because despite you know that the dictionary is within a list, you're trying to access the dictionary as if it wasn't within a list.

This is really important : this API can return more than one dictionary in the results list - see the totalResults key.

The best way to get the results is to do a for ... range loop:

for idx in range(crypto_data['totalResults']): print(crypto_data['results'][idx])