Splitting a DynamoDB result into a 2D array in Python

Question

I am trying to split this array in Python that I pulled down from a DynamoDB table into separate chunks so that I can then calculate the Averages of each AssetID, storing the AssetID and the Rating into separate parts of the Array.

[{'ID': Decimal('0'), 'AssetID': Decimal('0'), 'Rating': Decimal('3')}, {'ID': Decimal('1'), 'AssetID': Decimal('0'), 'Rating': Decimal('5')}]

So for example, I would like the array to look like the following:

AssetIDArray[AssetID][Rating]

So hence if I were to print the following, I would get 5.

AssetIDArray[0][1]

Thanks in advance for the help!

Answer 1

You need a dict instead of a list as AssetIDs:

from decimal import Decimal

items = [{'ID': Decimal('0'), 'AssetID': Decimal('0'), 'Rating': Decimal('3')},
         {'ID': Decimal('1'), 'AssetID': Decimal('0'), 'Rating': Decimal('5')}]

parsed_item_list = {}

for item in items:
    assetId = int(item.get('AssetID'))
    rating = int(item.get('Rating'))
    if assetId not in parsed_item_list:
        parsed_item_list[assetId] = []
    parsed_item_list[assetId].append(rating)

print(parsed_item_list.get(0)[0]) # 3
print(parsed_item_list.get(0)[1]) # 5