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How to change all datetime objects in a list to standard YYYY-MM-DD HH:MM:SS

When I query MySQL with Python and the query has datetime fields then I get this list as a result.
[{'_id': 1, 'name': 'index', '_cdate': datetime.datetime(2020, 10, 27, 9, 4, 34), 'title': 'DataExtract'}, {'_id': 2, 'name': 'topmenu', '_cdate': datetime.datetime(2020, 11, 4, 19, 52, 17), 'title': 'topmenu'}, {'_id': 3, 'name': 'functions_common', '_cdate': datetime.datetime(2020, 11, 4, 19, 52, 50), 'title': 'common functions'}, {'_id': 4, 'name': 'leftmenu', '_cdate': datetime.datetime(2020, 11, 4, 19, 53, 56), 'title': 'Left Menu'}, {'_id': 5, 'name': 'todo', '_cdate': datetime.datetime(2020, 11, 7, 8, 49, 38), 'title': 'Todo'}, {'_id': 6, 'name': 'cron_publish', '_cdate': datetime.datetime(2020, 12, 2, 19, 30, 11), 'title': 'Run Publish reports'}, {'_id': 7, 'name': 'test', '_cdate': datetime.datetime(2020, 12, 2, 22, 32, 54), 'title': 'test'}, {'_id': 8, 'name': 'help', '_cdate': datetime.datetime(2020, 12, 5, 7, 12, 44), 'title': 'Help'}, {'_id': 9, 'name': 'api', '_cdate': datetime.datetime(2020, 12, 5, 21, 22, 13), 'title': 'API'}, {'_id': 10, 'name': 'ben', '_cdate': datetime.datetime(2021, 10, 4, 11, 37, 3), 'title': 'List of Reports'}]
How do I either get the query to return the date fields in YYYY-MM-DD HH:MM:SS format? Or how do I convert them in the returned list. When I try to change them by enumerating over the results python throw as error that the dictionary has changed.

The datetime.datetime() objects you're getting are the standard representation of these objects - if you were expecting strings instead, you could simple convert them with datetime.strftime('%Y-%m-%d %H:%M:%S', value) but keep in mind that the datetime object is a more flexible way of keeping the data around. I'd recommend only formatting the date in a specific way if you're writing it to the screen or a file format that expects a string.
Example:
data = [{'_id': 1, 'name': 'index', '_cdate': datetime.datetime(2020, 10, 27, 9, 4, 34), 'title': 'DataExtract'}, {'_id': 2, 'name': 'topmenu', '_cdate': datetime.datetime(2020, 11, 4, 19, 52, 17), 'title': 'topmenu'}, {'_id': 3, 'name': 'functions_common', '_cdate': datetime.datetime(2020, 11, 4, 19, 52, 50), 'title': 'common functions'}, {'_id': 4, 'name': 'leftmenu', '_cdate': datetime.datetime(2020, 11, 4, 19, 53, 56), 'title': 'Left Menu'}, {'_id': 5, 'name': 'todo', '_cdate': datetime.datetime(2020, 11, 7, 8, 49, 38), 'title': 'Todo'}, {'_id': 6, 'name': 'cron_publish', '_cdate': datetime.datetime(2020, 12, 2, 19, 30, 11), 'title': 'Run Publish reports'}, {'_id': 7, 'name': 'test', '_cdate': datetime.datetime(2020, 12, 2, 22, 32, 54), 'title': 'test'}, {'_id': 8, 'name': 'help', '_cdate': datetime.datetime(2020, 12, 5, 7, 12, 44), 'title': 'Help'}, {'_id': 9, 'name': 'api', '_cdate': datetime.datetime(2020, 12, 5, 21, 22, 13), 'title': 'API'}, {'_id': 10, 'name': 'ben', '_cdate': datetime.datetime(2021, 10, 4, 11, 37, 3), 'title': 'List of Reports'}]
for rec in data:
rec['date_str'] = datetime.datetime.strftime('%Y-%m-%d %H:%M:%S', rec['_cdate'])
That would add 'date_str' field to every record with the format you require. Of course, you could also modify it to overwrite the original value.

Pandas ticker to ohlc

rows is a list of dict from mysql.
rows example
[{'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605515L, 'price': Decimal('1080.04000000'), 'type': 1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605549L, 'price': Decimal('1081.55000000'), 'type': 1, 'amount': Decimal('16.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605547L, 'price': Decimal('1081.33000000'), 'type': 1, 'amount': Decimal('20.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605545L, 'price': Decimal('1081.30000000'), 'type': 1, 'amount': Decimal('16.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605543L, 'price': Decimal('1081.29000000'), 'type': 1, 'amount': Decimal('20.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605541L, 'price': Decimal('1080.46000000'), 'type': 1, 'amount': Decimal('26.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 20), 'tid': 648605517L, 'price': Decimal('1080.04000000'), 'type': 1, 'amount': Decimal('8.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 22), 'tid': 648605601L, 'price': Decimal('1079.69000000'), 'type': -1, 'amount': Decimal('70.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 25), 'tid': 648605686L, 'price': Decimal('1079.72000000'), 'type': -1, 'amount': Decimal('4.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605765L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605753L, 'price': Decimal('1079.60000000'), 'type': -1, 'amount': Decimal('106.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605751L, 'price': Decimal('1079.60000000'), 'type': -1, 'amount': Decimal('80.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605749L, 'price': Decimal('1079.67000000'), 'type': -1, 'amount': Decimal('430.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605747L, 'price': Decimal('1079.70000000'), 'type': -1, 'amount': Decimal('66.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 26), 'tid': 648605745L, 'price': Decimal('1079.74000000'), 'type': -1, 'amount': Decimal('12.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 27), 'tid': 648605785L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 27), 'tid': 648605774L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 27), 'tid': 648605771L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('14.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 28), 'tid': 648605827L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('42.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 28), 'tid': 648605842L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 32), 'tid': 648605973L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 37), 'tid': 648606114L, 'price': Decimal('1079.44000000'), 'type': 1, 'amount': Decimal('24.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 37), 'tid': 648606116L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('40.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 42), 'tid': 648606258L, 'price': Decimal('1079.45000000'), 'type': 1, 'amount': Decimal('56.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 45), 'tid': 648606345L, 'price': Decimal('1079.46000000'), 'type': -1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 46), 'tid': 648606392L, 'price': Decimal('1079.69000000'), 'type': 1, 'amount': Decimal('44.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 48), 'tid': 648606418L, 'price': Decimal('1079.60000000'), 'type': -1, 'amount': Decimal('40.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 48), 'tid': 648606420L, 'price': Decimal('1079.46000000'), 'type': -1, 'amount': Decimal('36.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 48), 'tid': 648606422L, 'price': Decimal('1079.46000000'), 'type': -1, 'amount': Decimal('94.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 50), 'tid': 648606499L, 'price': Decimal('1079.31000000'), 'type': 1, 'amount': Decimal('80.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 50), 'tid': 648606478L, 'price': Decimal('1079.31000000'), 'type': -1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 50), 'tid': 648606476L, 'price': Decimal('1079.31000000'), 'type': -1, 'amount': Decimal('34.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 50), 'tid': 648606474L, 'price': Decimal('1079.55000000'), 'type': -1, 'amount': Decimal('8.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 55), 'tid': 648606666L, 'price': Decimal('1079.31000000'), 'type': 1, 'amount': Decimal('44.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 55), 'tid': 648606650L, 'price': Decimal('1079.17000000'), 'type': 1, 'amount': Decimal('8.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 27, 55), 'tid': 648606648L, 'price': Decimal('1079.17000000'), 'type': 1, 'amount': Decimal('8.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 1), 'tid': 648606820L, 'price': Decimal('1079.03000000'), 'type': -1, 'amount': Decimal('28.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 2), 'tid': 648606825L, 'price': Decimal('1079.03000000'), 'type': 1, 'amount': Decimal('30.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 2), 'tid': 648606836L, 'price': Decimal('1079.02000000'), 'type': -1, 'amount': Decimal('22.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 5), 'tid': 648606945L, 'price': Decimal('1078.58000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 5), 'tid': 648606943L, 'price': Decimal('1078.61000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 5), 'tid': 648606941L, 'price': Decimal('1078.63000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 5), 'tid': 648606939L, 'price': Decimal('1078.88000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 5), 'tid': 648606926L, 'price': Decimal('1078.88000000'), 'type': -1, 'amount': Decimal('428.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606984L, 'price': Decimal('1078.58000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606982L, 'price': Decimal('1078.05000000'), 'type': -1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606971L, 'price': Decimal('1078.58000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606957L, 'price': Decimal('1078.05000000'), 'type': -1, 'amount': Decimal('74.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606955L, 'price': Decimal('1078.15000000'), 'type': -1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606953L, 'price': Decimal('1078.15000000'), 'type': -1, 'amount': Decimal('14.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 6), 'tid': 648606951L, 'price': Decimal('1078.42000000'), 'type': -1, 'amount': Decimal('16.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 7), 'tid': 648606992L, 'price': Decimal('1078.05000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 7), 'tid': 648606995L, 'price': Decimal('1078.58000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 7), 'tid': 648607023L, 'price': Decimal('1078.06000000'), 'type': -1, 'amount': Decimal('4.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 8), 'tid': 648607047L, 'price': Decimal('1078.86000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 10), 'tid': 648607113L, 'price': Decimal('1078.06000000'), 'type': -1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 10), 'tid': 648607115L, 'price': Decimal('1078.03000000'), 'type': -1, 'amount': Decimal('148.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 12), 'tid': 648607192L, 'price': Decimal('1079.00000000'), 'type': -1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 13), 'tid': 648607218L, 'price': Decimal('1078.99000000'), 'type': 1, 'amount': Decimal('98.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 13), 'tid': 648607220L, 'price': Decimal('1079.00000000'), 'type': 1, 'amount': Decimal('42.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 13), 'tid': 648607222L, 'price': Decimal('1079.03000000'), 'type': 1, 'amount': Decimal('342.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 13), 'tid': 648607224L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('512.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 14), 'tid': 648607250L, 'price': Decimal('1078.98000000'), 'type': 1, 'amount': Decimal('44.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 14), 'tid': 648607252L, 'price': Decimal('1078.98000000'), 'type': 1, 'amount': Decimal('12.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 14), 'tid': 648607254L, 'price': Decimal('1079.00000000'), 'type': 1, 'amount': Decimal('106.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 14), 'tid': 648607256L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('40.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 20), 'tid': 648607431L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('28.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 20), 'tid': 648607429L, 'price': Decimal('1079.01000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 20), 'tid': 648607427L, 'price': Decimal('1079.01000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 23), 'tid': 648607518L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('8.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 24), 'tid': 648607544L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('344.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 25), 'tid': 648607593L, 'price': Decimal('1078.79000000'), 'type': -1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 26), 'tid': 648607631L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('430.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 26), 'tid': 648607623L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('18.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 26), 'tid': 648607621L, 'price': Decimal('1078.79000000'), 'type': 1, 'amount': Decimal('14.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 29), 'tid': 648607695L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('776.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 32), 'tid': 648607803L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 32), 'tid': 648607805L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('10.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 36), 'tid': 648607905L, 'price': Decimal('1079.16000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 37), 'tid': 648607940L, 'price': Decimal('1079.31000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 42), 'tid': 648608110L, 'price': Decimal('1079.46000000'), 'type': -1, 'amount': Decimal('12.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 46), 'tid': 648608211L, 'price': Decimal('1079.88000000'), 'type': -1, 'amount': Decimal('12.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 46), 'tid': 648608213L, 'price': Decimal('1079.88000000'), 'type': -1, 'amount': Decimal('6.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 57), 'tid': 648608534L, 'price': Decimal('1080.29000000'), 'type': 1, 'amount': Decimal('14.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 28, 57), 'tid': 648608536L, 'price': Decimal('1080.30000000'), 'type': 1, 'amount': Decimal('2.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 29, 2), 'tid': 648608683L, 'price': Decimal('1080.59000000'), 'type': 1, 'amount': Decimal('40.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 29, 3), 'tid': 648608733L, 'price': Decimal('1080.59000000'), 'type': 1, 'amount': Decimal('360.00000000')}, {'date': datetime.datetime(2017, 3, 21, 13, 29, 7), 'tid': 648608838L, 'price': Decimal('1080.90000000'), 'type': 1, 'amount': Decimal('82.00000000')}]
if I didn't use set_index ,it will have an TypeError: Only valid with DatetimeIndex, TimedeltaIndex or PeriodIndex, but got an instance of 'RangeIndex'
if rows:
df = pd.DataFrame(rows)
print df.head()
# TypeError: Only valid with DatetimeIndex, TimedeltaIndex or PeriodIndex, but got an instance of 'RangeIndex'
df = df.set_index("date")
print df.head()
resample_data = df.resample("1min", how={"price": "ohlc", "amount": "sum"})
print resample_data
Result :
Connected to pydev debugger (build 162.1967.10)
amount date price tid type
0 2.00000000 2017-03-21 11:15:12 1075.83000000 648370156 -1
1 10.00000000 2017-03-21 11:15:15 1076.00000000 648370241 -1
2 10.00000000 2017-03-21 11:15:17 1075.83000000 648370297 -1
3 10.00000000 2017-03-21 11:15:17 1075.83000000 648370311 1
4 8.00000000 2017-03-21 11:15:19 1076.13000000 648370370 1
amount price tid type
date
2017-03-21 11:15:12 2.00000000 1075.83000000 648370156 -1
2017-03-21 11:15:15 10.00000000 1076.00000000 648370241 -1
2017-03-21 11:15:17 10.00000000 1075.83000000 648370297 -1
2017-03-21 11:15:17 10.00000000 1075.83000000 648370311 1
2017-03-21 11:15:19 8.00000000 1076.13000000 648370370 1
/Users/wyx/bitcoin_workspace/fibo-strategy/ticker.py:45: FutureWarning: how in .resample() is deprecated
the new syntax is .resample(...)..apply(<func>)
resample_data = df.resample("1min", how={"price": "ohlc", "amount": "sum"})
Traceback (most recent call last):
File "/Applications/PyCharm.app/Contents/helpers/pydev/pydevd.py", line 1580, in <module>
globals = debugger.run(setup['file'], None, None, is_module)
File "/Applications/PyCharm.app/Contents/helpers/pydev/pydevd.py", line 964, in run
pydev_imports.execfile(file, globals, locals) # execute the script
File "/Users/wyx/bitcoin_workspace/fibo-strategy/ticker.py", line 45, in <module>
resample_data = df.resample("1min", how={"price": "ohlc", "amount": "sum"})
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/generic.py", line 4216, in resample
limit=limit)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/tseries/resample.py", line 582, in _maybe_process_deprecations
r = r.aggregate(how)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/tseries/resample.py", line 320, in aggregate
result, how = self._aggregate(arg, *args, **kwargs)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/base.py", line 549, in _aggregate
result = _agg(arg, _agg_1dim)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/base.py", line 500, in _agg
result[fname] = func(fname, agg_how)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/base.py", line 483, in _agg_1dim
return colg.aggregate(how, _level=(_level or 0) + 1)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/groupby.py", line 2652, in aggregate
return getattr(self, func_or_funcs)(*args, **kwargs)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/groupby.py", line 1128, in ohlc
lambda x: x._cython_agg_general('ohlc'))
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/groupby.py", line 3103, in _apply_to_column_groupbys
return func(self)
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/groupby.py", line 1128, in <lambda>
lambda x: x._cython_agg_general('ohlc'))
File "/Users/wyx/bitcoin_workspace/fibo-strategy/.env/lib/python2.7/site-packages/pandas/core/groupby.py", line 808, in _cython_agg_general
raise DataError('No numeric types to aggregate')
pandas.core.base.DataError: No numeric types to aggregate
Process finished with exit code 1
I am a rookie for pandas.
How solve the error?
And if I want to use the last close price to fill the NaN of next
min ohlc. How to do that?

You need to set an index using your dates.
Code:
from io import StringIO
df = pd.read_csv(StringIO(
u"""amount date price tid type
6.00000000 2017-03-21t10:46:32 1059.26000000 648313975 -1
4.00000000 2017-03-21t10:46:37 1059.42000000 648314094 -1
2.00000000 2017-03-21t10:46:37 1059.42000000 648314096 -1
2.00000000 2017-03-21t10:46:41 1059.26000000 648314176 -1
32.00000000 2017-03-21t10:46:41 1059.26000000 648314189 -1
"""), sep='\s+', parse_dates='date'.split())
print(df)
resample_data = df.set_index('date').resample(
"1min", how={"price": "ohlc", "amount": "sum"})
print(resample_data)
Results:
amount date price tid type
0 6.0 2017-03-21 10:46:32 1059.26 648313975 -1
1 4.0 2017-03-21 10:46:37 1059.42 648314094 -1
2 2.0 2017-03-21 10:46:37 1059.42 648314096 -1
3 2.0 2017-03-21 10:46:41 1059.26 648314176 -1
4 32.0 2017-03-21 10:46:41 1059.26 648314189 -1
price amount
open high low close amount
date
2017-03-21 10:46:00 1059.26 1059.42 1059.26 1059.26 46.0

How to write list of multilevel dictionaries into csv

I have a list of dictionaries stored in tweets, and I am trying to write these into a csv file using writerows method.
Sample List looks something like this:
[{'sentiment': 'Unknown', 'date': datetime.datetime(2013, 1, 1, 5, 31, 32), 'body': 'mcd brk b'},
{'sentiment': 'Unknown', 'date': datetime.datetime(2013, 1, 1, 6, 55, 23), 'body': 'co hihq'},
{'sentiment': {'basic': 'Bullish'}, 'date': datetime.datetime(2013, 1, 1, 7, 36, 32), 'body': 'new year bac'}]
Here sentiment key has either one level or two. I am trying to write these dictionaries into a csv format such that I only have the values of these keys for above either 'Unknown' or 'Bullish'.
file = open('BAC.csv','w')
keys=tweets[0].keys()
dict_writer=csv.DictWriter(file,keys)
dict_writer.writerows(tweets)
I get the csv file in the following format
Unknown,2013-01-01 05:31:32,mcd brk b
Unknown,2013-01-01 06:55:23,co hihq
{'basic': 'Bullish'},2013-01-01 07:36:32,mnew year bac
But I need it as
Unknown,2013-01-01 05:31:32,mcd brk b
Unknown,2013-01-01 06:55:23,co hihq
Bullish,2013-01-01 07:36:32,mnew year bac
Is there any easy way to do this? In many instances the levels go up to five, but similar deal just need the value.

You will need to write a function to flatten these sentiment values.
Something like this could work if you have only one element in each level.
def flatten(row, field):
if isinstance(row[field], dict):
row[field] = row[field].values()[0]
return flatten(row, field)
return row
Then you would need to call this method on each row before writing it to the csv.
tweets = [{'sentiment': 'Unknown', 'date': datetime.datetime(2013, 1, 1, 5, 31, 32), 'body': 'mcd brk b'},
{'sentiment': 'Unknown', 'date': datetime.datetime(2013, 1, 1, 6, 55, 23), 'body': 'co hihq'},
{'sentiment': {'basic': {'text': 'Bullish' } }, 'date': datetime.datetime(2013, 1, 1, 7, 36, 32), 'body': 'new year bac'}]
print [flatten(row, 'sentiment') for row in tweets]
Output
[{'date': datetime.datetime(2013, 1, 1, 5, 31, 32), 'body': 'mcd brk b', 'sentiment': 'Unknown'},
{'date': datetime.datetime(2013, 1, 1, 6, 55, 23), 'body': 'co hihq', 'sentiment': 'Unknown'},
{'date': datetime.datetime(2013, 1, 1, 7, 36, 32), 'body': 'new year bac', 'sentiment': 'Bullish'}]

Remove duplicated from list of dict- python [duplicate]

This question already has answers here:
Remove duplicates from a list of dictionaries when only one of the key values is different
(5 answers)
Closed 8 years ago.
I have list of dictionaries, I want to remove duplicates from that list. How to do that ?
a = [
{'dtstart': '2014-09-10T08:00:00',
'end': datetime.datetime(2014, 9, 10, 9, 0),
'location': 'Brady Auditorium, B-131',
'partial_date': datetime.date(2014, 9, 10),
'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700',
'start': datetime.datetime(2014, 9, 10, 8, 0),
'stream': '01a331e2-42be-4622-b072-0c42b55b436e',
'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
'uid': '2d671415-c666-498f-a401-01652a08e4b3'},
{'dtstart': '2014-09-10T08:00:00',
'end': datetime.datetime(2014, 9, 10, 9, 0),
'location': 'Brady Auditorium, B-131',
'partial_date': datetime.date(2014, 9, 10),
'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700',
'start': datetime.datetime(2014, 9, 10, 8, 0),
'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c',
'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
'uid': '2d671415-c666-498f-a401-01652a08e4b3'}
]
What I have tried is ,
>>> [dict(t) for t in set([tuple(d.items()) for d in a])]
But still returning duplicate elements.

Just try the following code:
{document['uid']: document for document in a}.values()
For every uuid you will get the latest document. If you're looking for the first entries, try this:
{document['uid']: document for document in a[::-1]}.values()

Use a dictionary comprehension to create a dictionary with uid as keys and each dictionary as values. Then extract the values to return a list of unique dictionaries as keyed by uid.
>>> a=[{'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': '01a331e2-42be-4622-b072-0c42b55b436e', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}, {'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}]
>>> {d['uid']: d for d in a}.values()
[{'dtstart': '2014-09-10T08:00:00',
'end': datetime.datetime(2014, 9, 10, 9, 0),
'location': 'Brady Auditorium, B-131',
'partial_date': datetime.date(2014, 9, 10),
'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700',
'start': datetime.datetime(2014, 9, 10, 8, 0),
'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c',
'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
'uid': '2d671415-c666-498f-a401-01652a08e4b3'}]

Try appending the uids to a temporary list and verify with present dictionary
import datetime
a=[{'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': '01a331e2-42be-4622-b072-0c42b55b436e', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'},
{'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}]
uuids = set() # temperary set holds UID
final=[]
for i in a:
if i['uid'] not in uuids:
final.append(i)
uuids.add(i['uid'])
print final

Grouping data on year

mydata = [{'date': datetime.datetime(2009, 1, 31, 0, 0), 'value': 14, 'year': u'2009'},
{'date': datetime.datetime(2009, 2, 28, 0, 0), 'value': 84, 'year': u'2009'},
{'date': datetime.datetime(2009, 3, 31, 0, 0), 'value': 77, 'year': u'2009'},
{'date': datetime.datetime(2009, 4, 30, 0, 0), 'value': 80, 'year': u'2009'},
{'date': datetime.datetime(2009, 5, 31, 0, 0), 'value': 6, 'year': u'2009'},
{'date': datetime.datetime(2009, 6, 30, 0, 0), 'value': 16, 'year': u'2009'},
{'date': datetime.datetime(2009, 7, 31, 0, 0), 'value': 16, 'year': u'2009'},
{'date': datetime.datetime(2009, 8, 31, 0, 0), 'value': 1, 'year': u'2009'},
{'date': datetime.datetime(2009, 9, 30, 0, 0), 'value': 9, 'year': u'2009'},
{'date': datetime.datetime(2008, 1, 31, 0, 0), 'value': 77, 'year': u'2008'},
{'date': datetime.datetime(2008, 2, 29, 0, 0), 'value': 60, 'year': u'2008'},
{'date': datetime.datetime(2008, 3, 31, 0, 0), 'value': 28, 'year': u'2008'},
{'date': datetime.datetime(2008, 4, 30, 0, 0), 'value': 9, 'year': u'2008'},
{'date': datetime.datetime(2008, 5, 31, 0, 0), 'value': 74, 'year': u'2008'},
{'date': datetime.datetime(2008, 6, 30, 0, 0), 'value': 70, 'year': u'2008'},
{'date': datetime.datetime(2008, 7, 31, 0, 0), 'value': 75, 'year': u'2008'},
{'date': datetime.datetime(2008, 8, 31, 0, 0), 'value': 7, 'year': u'2008'},
{'date': datetime.datetime(2008, 9, 30, 0, 0), 'value': 10, 'year': u'2008'},
{'date': datetime.datetime(2008, 10, 31, 0, 0), 'value': 54, 'year': u'2008'},
{'date': datetime.datetime(2008, 11, 30, 0, 0), 'value': 55, 'year': u'2008'},
{'date': datetime.datetime(2008, 12, 31, 0, 0), 'value': 40, 'year': u'2008'},
{'date': datetime.datetime(2007, 12, 31, 0, 0), 'value': 93, 'year': u'2007'},]
In 'mydata', I get list of sequential monthly data. I wrote some code to group them on year.
partial_req_data = dict([(k,[f for f in v]) for k,v in itertools.groupby(mydata, key=lambda x : x.get('year'))])
Now I further need some efficient code to fill the missing months with {}, i.e. empty dict. There are bad ways to do that, but am looking for good ones.
required_data = {"2009": [{'date': datetime.datetime(2009, 1, 31, 0, 0), 'value': 14, 'year': u'2009' },
{'date': datetime.datetime(2009, 2, 28, 0, 0), 'value': 84, 'year': u'2009'},
{'date': datetime.datetime(2009, 3, 31, 0, 0), 'value': 77, 'year': u'2009'},
{'date': datetime.datetime(2009, 4, 30, 0, 0), 'value': 80, 'year': u'2009'},
{'date': datetime.datetime(2009, 5, 31, 0, 0), 'value': 6, 'year': u'2009'},
{'date': datetime.datetime(2009, 6, 30, 0, 0), 'value': 16, 'year': u'2009'},
{'date': datetime.datetime(2009, 7, 31, 0, 0), 'value': 16, 'year': u'2009'},
{'date': datetime.datetime(2009, 8, 31, 0, 0), 'value': 1, 'year': u'2009'},
{'date': datetime.datetime(2009, 9, 30, 0, 0), 'value': 9, 'year': u'2009'},
{}, {}, {}],
"2008": [{'date': datetime.datetime(2008, 1, 31, 0, 0), 'value': 77, 'year': u'2008'},
{'date': datetime.datetime(2008, 2, 29, 0, 0), 'value': 60, 'year': u'2008'},
{'date': datetime.datetime(2008, 3, 31, 0, 0), 'value': 28, 'year': u'2008'},
{'date': datetime.datetime(2008, 4, 30, 0, 0), 'value': 9, 'year': u'2008'},
{'date': datetime.datetime(2008, 5, 31, 0, 0), 'value': 74, 'year': u'2008'},
{'date': datetime.datetime(2008, 6, 30, 0, 0), 'value': 70, 'year': u'2008'},
{'date': datetime.datetime(2008, 7, 31, 0, 0), 'value': 75, 'year': u'2008'},
{'date': datetime.datetime(2008, 8, 31, 0, 0), 'value': 7, 'year': u'2008'},
{'date': datetime.datetime(2008, 9, 30, 0, 0), 'value': 10, 'year': u'2008'},
{'date': datetime.datetime(2008, 10, 31, 0, 0), 'value': 54, 'year': u'2008'},
{'date': datetime.datetime(2008, 11, 30, 0, 0), 'value': 55, 'year': u'2008'},
{'date': datetime.datetime(2008, 12, 31, 0, 0), 'value': 40, 'year': u'2008'},]
"2007": [{}, {}, {}, {}, {}, {}, {}, {}, {}, {}, {},
{'date': datetime.datetime(2007, 12, 31, 0, 0), 'value': 93, 'year': u'2007'}]
}

import datetime
from itertools import groupby
from pprint import pprint
required_data={}
for k,g in groupby(mydata,key=lambda x: x.get('year')):
partial={}
for datum in g:
partial[datum.get('date').month]=datum
required_data[k]=[partial.get(m,{}) for m in range(1,13)]
pprint(required_data)
For each year k, partial is a dict whose keys are months.
The trick is to use partial.get(m,{}) since this will return the datum when it exists, or {} when it does not.