How to add values of a json request in python?

Question

Example:

request = requests.get('https://api.amountofsomething.com')
amount = request.json()['amount']

This request returns values like these:

[{"amount": 0.1}, {"amount": 2},{"amount": 145},{"amount": 5.84}]

I need to do sums, without patterns, of different index values. I have done so, and it has worked, but for large amounts of data the code gets very extensive.

amount0 = amount[0]['amount']

amount1 = amount[1]['amount']

amount2 = amount[2]['amount']

sum0 = amount0 + amount2 >>> sum0 = 0.1 + 145

...

I tried in different ways, to manipulate this data to generate less code.

sum0 =  amount [0+2]['amount']

sum1 = amount [[0] + [2]]['amount']

sum2 = amount [0]['amount'] + amount [2]['amount']

None of those options worked, can anyone give me a hand ?

Answer 1

If your answer comes from the way:

amounts = [{"amount": 0.1}, {"amount": 2}, {"amount": 145}, {"amount": 5.84}]

And you need to add up all the values, just do:

total = sum(it['amount'] for it in amounts)

Thus, it will add up regardless of the amount of items that comes in the answer.

Answer 2

Assuming you have a list of dictionaries returning in this api we have:

amounts = [
        {"amount": 0.1},
        {"amount": 2},
        {"amount": 145},
        {"amount": 5.84}
    ]

You could iterate over that list by summing up the indices..

soma = 0

for amount in amounts[0:15]:
    soma += amount.get("amount",0)

Or use list comprehension

soma = sum(amount.get("amount",0) for amount in amounts[0:15])

EDIT: Change to add only the first 15 indexes of the returned data.

The counting of items starts at 0 and goes up to max-1 , in case 15-1 = 14... Thus from index 0 to 14 are 15 values.

Answer 3

You have multiple dictionaries within a list, so we can access these dictionaries with a for:

req = [{"amount": 0.1}, {"amount": 2},{"amount": 145},{"amount": 5.84}]

soma = 0
for dic in req:
    soma += dic['amount']

>>> print soma
152.94

Edit:

Look at

req[0] = {"amount": 0.1} #Primeiro item da lista é um dicionario
req[1] = {"amount": 2}

req[0]['amount'] = 0.1 #Assim acessamos o valor
req[1]['amount'] = 2

So to add up only the first two indices, for example, we can do:

soma = 0
for i in range(0,2):
    soma += req[i]['amount']

>>> print (soma)
2.1