Fixing scientific notation in json to float

Question

I'm currently stuck on how to change the output of a JSON file from having scientific notation to having a float for some of the keys in the JSON dict.

for example I need this:

{'message': '', 'result': [{'Ask': 8.982e-05, 'BaseVolume': 235.09663206, 'Bid': 8.9e-05, 'Created': '2017-06-06T01:22:35.727', 'High': 9.413e-05, 'Last': 8.878e-05, 'Low': 8.01e-05, 'MarketName': 'BTC-1ST', 'OpenBuyOrders': 408, 'OpenSellOrders': 6009, 'PrevDay': 8.375e-05, 'TimeStamp': '2017-09-27T02:17:44.677', 'Volume': 2678614.34426254},

to look like this:

{"success":true,"message":"","result":[{"MarketName":"BTC-1ST","High":0.00009413,"Low":0.00008010,"Volume":2678614.34426254,"Last":0.00008878,"BaseVolume":235.09663206,"TimeStamp":"2017-09-27T02:13:07.55","Bid":0.00008900,"Ask":0.00008982,"OpenBuyOrders":408,"OpenSellOrders":6009,"PrevDay":0.00008375,"Created":"2017-06-06T01:22:35.727"},

my current code just looks like this:

#!/usr/bin/python3

import urllib.request, json
from pprint import pprint
from json import encoder

encoder.FLOAT_REPR = lambda o: format(o, '.8f')
with urllib.request.urlopen("https://bittrex.com/api/v1.1/public/getmarketsummaries") as url:
    data = json.loads(url.read().decode())
    pprint (data)

that DOES NOT WORK even though my previous question was marked answered and a duplicate question of another question. That "duplicate" question had nothing to do with scientific notation and DID NOT fix the problem.

You are using json to read the file and pprint to display it on the console. You seem to be concerned with how the data is displayed, which would be a property of pprint not json. Do you mean to ask how to change the default formatting of floating point values in pprint? — Paul Cornelius, Sep 27 '17 at 05:48
This is a case of confusing the map for the territory; the data is a float, scientific notation is a format for representing a float as a string, and it's a permitted representation in both the JSON format and by Python's `float` function which can parse a string as a floating-point value. — kaya3, Mar 01 '21 at 18:06

Alperen · Answer 1 · 2021-03-01T17:20:41.977

Maybe, it will cause some problems, but they are easy to fix. You need to use json.dumps() instead of json.loads() Source

data = json.dumps(url.read().decode())

Output:

'"{\"success\":true,\"message\":\"\",\"result\":[{\"MarketName\":\"BTC-1ST\",\"High\":0.00009287,\"Low\":0.00008200,\"Volume\":1860886.81706592,\"Last\":0.00008800,\"BaseVolume\":163.34599977,\"TimeStamp\":\"2017-09-27T07:54:48.62\",\"Bid\":0.00008800,\"Ask\":0.00008818,\"OpenBuyOrders\":401,\"OpenSellOrders\":6015,\" ...

score 1 · Accepted Answer · answered Sep 27 '17 at 07:52

Those values are already stored as floats! You can see this with the following code (modified from yours):

#!/usr/bin/python3

import urllib.request, json
from pprint import pprint
from json import encoder

encoder.FLOAT_REPR = lambda o: format(o, '.8f')
with urllib.request.urlopen("https://bittrex.com/api/v1.1/public/getmarketsummaries") as url:
    data = json.loads(url.read().decode())
    # pprint (data)
    thing = list(filter(lambda x:x['MarketName']=='BTC-1ST', data['result']))[0]
    pprint(thing['Ask'])
    print('{:.10f}'.format(thing['Ask']))
    print(type(thing['Ask']))

Notice how the first value from pprint shows scientific notation (ie. the default string representation of that float value), while the second shows it formatted similar to how you are wanting it by forcing it to display that way.

So, if you're wanting to simply print out one of those values, you'll have to use string formatting as in my example, or if you want to pass those values to another program or function, you don't have to change anything since they are already floats!

Fixing scientific notation in json to float

2 Answers2