如何将样本特征数据整理为指定格式的Python字典？

Got it, let's walk through how to turn your raw data into the dictionary you need. It's simpler than it sounds—here's a step-by-step breakdown with Python code:

Step 1: Define Your Raw Data #

First, let's structure your input into a list of lists (this is how you'd typically store this kind of data in Python):

raw_data = [
    ['10', '0', '1915', '387', '1933', '402'],
    ['10', '0', '3350', '387', '3407', '391'],
    ['10', '0', '842', '505', '863', '521'],
    ['2', '29', '2986', '282', '3112', '300'],
    ['2', '29', '2753', '286', '2809', '297']
]

Step 2: Build the Dictionary #

You have two straightforward options here—either use a regular dictionary with a quick check for existing keys, or use collections.defaultdict to simplify the code:

Option 1: Regular Dictionary (No Extra Imports) #

This works perfectly if you don't want to pull in any additional modules:

# Start with an empty dictionary to hold our final result
result = {}

for item in raw_data:
    # Create the key in "feature1-feature2" format using an f-string
    key = f"{item[0]}-{item[1]}"
    # Convert the last 4 string elements to integers and make a sublist
    values = list(map(int, item[2:]))
    
    # Add the sublist to the dictionary: append if the key already exists, create a new entry if not
    if key in result:
        result[key].append(values)
    else:
        result[key] = [values]

Option 2: Using collections.defaultdict (Cleaner Code) #

This shortcut eliminates the need to check if the key exists, making the logic more concise:

from collections import defaultdict

# Initialize a defaultdict that automatically creates empty lists for new keys
result = defaultdict(list)

for item in raw_data:
    key = f"{item[0]}-{item[1]}"
    values = list(map(int, item[2:]))
    # Just append directly—no conditional check needed!
    result[key].append(values)

# (Optional) Convert back to a regular dictionary if you prefer that type
result = dict(result)

Step 3: Verify the Result #

When you print result, you'll get exactly the structure you requested:

print(result)
# Output:
# {
#     '10-0': [[1915, 387, 1933, 402], [3350, 387, 3407, 391], [842, 505, 863, 521]],
#     '2-29': [[2986, 282, 3112, 300], [2753, 286, 2809, 297]]
# }

Quick Notes: #

• If you want to keep the numeric values as strings instead of integers, just remove the list(map(int, ...)) part and use item[2:] directly.
• The f-string (f"{item[0]}-{item[1]}") is the cleanest way to format your key, but you could also use item[0] + "-" + item[1] if you prefer.

内容的提问来源于stack exchange，提问作者user9266899