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NoahVerner
Asked: 2022-09-11 11:03:04 +0800 CST 2022-09-11 11:03:04 +0800 CST

How to get 2 different key values ​​from a list of dictionaries and add them to another list as sub-dictionaries?

  • 772

Let's say I have the following list of dictionaries called sorted_bearish_trading_pairs_info:

sorted_bearish_trading_pairs_info = [{'Trading Pair': 'TCTUSDT', '24h Change': -0.00845, '24h Volume(USDT)': 1926012.715, '0.5d ago Parkinson Volatility': 0.05589759007855682, '0.5d ago True Price Range': -0.03208065994500455, '0.5d ago Maximum Price Range': 0.02016498625114571, 'Last Close Price': 0.01056, 'Last Start Date UTC': Timestamp('2022-07-09 19:00:00')}, {'Trading Pair': 'NMRUSDT', '24h Change': 0.00605, '24h Volume(USDT)': 7340230.2529, '0.5d ago Parkinson Volatility': 0.058917395795956236, '0.5d ago True Price Range': -0.040945790080738224, '0.5d ago Maximum Price Range': 0.03402537485582467, 'Last Close Price': 16.63, 'Last Start Date UTC': Timestamp('2022-07-09 19:00:00')}, {'Trading Pair': 'STEEMUSDT', '24h Change': 0.11779999999999999, '24h Volume(USDT)': 16649505.68257, '0.5d ago Parkinson Volatility': 0.11376745797366504, '0.5d ago True Price Range': -0.05561653860226854, '0.5d ago Maximum Price Range': 0.03732162458836439, 'Last Close Price': 0.2581, 'Last Start Date UTC': Timestamp('2022-07-09 19:00:00')}, {'Trading Pair': 'WINGUSDT', '24h Change': 0.14821, '24h Volume(USDT)': 29672792.925, '0.5d ago Parkinson Volatility': 0.14523057363857397, '0.5d ago True Price Range': -0.05580029368575623, '0.5d ago Maximum Price Range': 0.08076358296622625, 'Last Close Price': 6.43, 'Last Start Date UTC': Timestamp('2022-07-09 19:00:00')}, {'Trading Pair': 'BTCSTUSDT', '24h Change': -0.16942000000000002, '24h Volume(USDT)': 34309469.117, '0.5d ago Parkinson Volatility': 0.15723835541618095, '0.5d ago True Price Range': -0.030425963488843705, '0.5d ago Maximum Price Range': 0.04462474645030439, 'Last Close Price': 9.56, 'Last Start Date UTC': Timestamp('2022-07-09 19:00:00')}]

Yes I run the following line:

[x["0.5d ago Parkinson Volatility"] for x in sorted_bearish_trading_pairs_info]

I get the value of each called key "0.5d ago Parkinson Volatility"from all the dictionaries in the list:

[0.05589759007855682,
 0.058917395795956236,
 0.11376745797366504,
 0.14523057363857397,
 0.15723835541618095]

Yes I run the following line:

[x["Trading Pair"] for x in sorted_bearish_trading_pairs_info]

I get the value of each called key "Trading Pair"from all the dictionaries in the list:

['TCTUSDT', 'NMRUSDT', 'STEEMUSDT', 'WINGUSDT', 'BTCSTUSDT']

Now, the question I have is how could I get the values ​​of both keys so that they end up being presented as the following list of dictionaries?

[{Trading Pair': 'TCTUSDT',
'0.5d ago Parkinson Volatility': 0.05589759007855682},
{'Trading Pair': 'NMRUSDT',
'0.5d ago Parkinson Volatility': 0.058917395795956236},
{'Trading Pair': 'STEEMUSDT',
'0.5d ago Parkinson Volatility': 0.11376745797366504},
{'Trading Pair': 'WINGUSDT',
'0.5d ago Parkinson Volatility': 0.14523057363857397},
{'Trading Pair': 'BTCSTUSDT',
'0.5d ago Parkinson Volatility': 0.15723835541618095}]
python-3.x

2 Answers

  1. Best Answer

    A solution:

    salida = []
for x in sorted_bearish_trading_pairs_info:
    nuevo = {"Trading Pair": x["Trading Pair"],
             "0.5d ago Parkinson Volatility": x["0.5d ago Parkinson Volatility"]
             }
    salida.append(nuevo)

    The foriterates through the dictionaries in the original list. For each dictionary, a new one is created with the two keys of interest and their respective values.

    This dictionary is added to the output list.

    show

    sorted_bearish_trading_pairs_info = [
    {'Trading Pair': 'TCTUSDT', '24h Change': -0.00845, '24h Volume(USDT)': 1926012.715,
     '0.5d ago Parkinson Volatility': 0.05589759007855682, '0.5d ago True Price Range': -0.03208065994500455,
     '0.5d ago Maximum Price Range': 0.02016498625114571, 'Last Close Price': 0.01056,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'NMRUSDT', '24h Change': 0.00605, '24h Volume(USDT)': 7340230.2529,
     '0.5d ago Parkinson Volatility': 0.058917395795956236, '0.5d ago True Price Range': -0.040945790080738224,
     '0.5d ago Maximum Price Range': 0.03402537485582467, 'Last Close Price': 16.63,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'STEEMUSDT', '24h Change': 0.11779999999999999, '24h Volume(USDT)': 16649505.68257,
     '0.5d ago Parkinson Volatility': 0.11376745797366504, '0.5d ago True Price Range': -0.05561653860226854,
     '0.5d ago Maximum Price Range': 0.03732162458836439, 'Last Close Price': 0.2581,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'WINGUSDT', '24h Change': 0.14821, '24h Volume(USDT)': 29672792.925,
     '0.5d ago Parkinson Volatility': 0.14523057363857397, '0.5d ago True Price Range': -0.05580029368575623,
     '0.5d ago Maximum Price Range': 0.08076358296622625, 'Last Close Price': 6.43,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'BTCSTUSDT', '24h Change': -0.16942000000000002, '24h Volume(USDT)': 34309469.117,
     '0.5d ago Parkinson Volatility': 0.15723835541618095, '0.5d ago True Price Range': -0.030425963488843705,
     '0.5d ago Maximum Price Range': 0.04462474645030439, 'Last Close Price': 9.56,
     'Last Start Date UTC': ('2022-07-09 19:00:00')}]

salida = []
for x in sorted_bearish_trading_pairs_info:
    nuevo = {"Trading Pair": x["Trading Pair"],
             "0.5d ago Parkinson Volatility": x["0.5d ago Parkinson Volatility"]
             }
    salida.append(nuevo)

for x in salida:
    print(x)

    produces:

    {'Trading Pair': 'TCTUSDT', '0.5d ago Parkinson Volatility': 0.05589759007855682}
{'Trading Pair': 'NMRUSDT', '0.5d ago Parkinson Volatility': 0.058917395795956236}
{'Trading Pair': 'STEEMUSDT', '0.5d ago Parkinson Volatility': 0.11376745797366504}
{'Trading Pair': 'WINGUSDT', '0.5d ago Parkinson Volatility': 0.14523057363857397}
{'Trading Pair': 'BTCSTUSDT', '0.5d ago Parkinson Volatility': 0.15723835541618095}

Process finished with exit code 0
    • 1

  2. This is a version of Candid Moe's answer that uses a function to avoid writing repetitive and unclear code:

    def extract_items(dct, *keys):
    return {key:dct[key] for key in keys}

# Esta lista de diccionarios viene de la respuesta de Candid Moe
sorted_bearish_trading_pairs_info = [
    {'Trading Pair': 'TCTUSDT', '24h Change': -0.00845, '24h Volume(USDT)': 1926012.715,
     '0.5d ago Parkinson Volatility': 0.05589759007855682, '0.5d ago True Price Range': -0.03208065994500455,
     '0.5d ago Maximum Price Range': 0.02016498625114571, 'Last Close Price': 0.01056,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'NMRUSDT', '24h Change': 0.00605, '24h Volume(USDT)': 7340230.2529,
     '0.5d ago Parkinson Volatility': 0.058917395795956236, '0.5d ago True Price Range': -0.040945790080738224,
     '0.5d ago Maximum Price Range': 0.03402537485582467, 'Last Close Price': 16.63,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'STEEMUSDT', '24h Change': 0.11779999999999999, '24h Volume(USDT)': 16649505.68257,
     '0.5d ago Parkinson Volatility': 0.11376745797366504, '0.5d ago True Price Range': -0.05561653860226854,
     '0.5d ago Maximum Price Range': 0.03732162458836439, 'Last Close Price': 0.2581,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'WINGUSDT', '24h Change': 0.14821, '24h Volume(USDT)': 29672792.925,
     '0.5d ago Parkinson Volatility': 0.14523057363857397, '0.5d ago True Price Range': -0.05580029368575623,
     '0.5d ago Maximum Price Range': 0.08076358296622625, 'Last Close Price': 6.43,
     'Last Start Date UTC': ('2022-07-09 19:00:00')},
    {'Trading Pair': 'BTCSTUSDT', '24h Change': -0.16942000000000002, '24h Volume(USDT)': 34309469.117,
     '0.5d ago Parkinson Volatility': 0.15723835541618095, '0.5d ago True Price Range': -0.030425963488843705,
     '0.5d ago Maximum Price Range': 0.04462474645030439, 'Last Close Price': 9.56,
     'Last Start Date UTC': ('2022-07-09 19:00:00')}]

print([extract_items(x, "Trading Pair", "0.5d ago Parkinson Volatility") for x in sorted_bearish_trading_pairs_info])

    The extract_items function takes a first argument that would be the dictionary, and infinite other arguments that would be the keys to be accessed, iterates through the keys, creating a new dictionary where the item is "copied" from the original dictionary.

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