im following the instructions to read data from influx into pandas and im getting the following error:
ValueError Traceback (most recent call last) <ipython-input-13-1e63a2e6d3db> in <module>()
----> 1 df = pd.DataFrame(AandCStation)
2
3 #AandCStation['time'] # gets the name
4
5 #AandCStation.values
C:\Users\user\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py in __init__(self, data, index, columns, dtype, copy)
328 dtype=dtype, copy=copy)
329 elif isinstance(data, dict):
--> 330 mgr = self._init_dict(data, index, columns, dtype=dtype)
331 elif isinstance(data, ma.MaskedArray):
332 import numpy.ma.mrecords as mrecords
C:\Users\user\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py in _init_dict(self, data, index, columns, dtype)
459 arrays = [data[k] for k in keys]
460
--> 461 return _arrays_to_mgr(arrays, data_names, index, columns, dtype=dtype)
462
463 def _init_ndarray(self, values, index, columns, dtype=None, copy=False):
C:\Users\user\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py in _arrays_to_mgr(arrays, arr_names, index, columns, dtype) 6161
# figure out the index, if necessary 6162 if index is None:
-> 6163 index = extract_index(arrays) 6164 else: 6165 index = _ensure_index(index)
C:\Users\user\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\frame.py in extract_index(data) 6200 6201 if not indexes and not raw_lengths:
-> 6202 raise ValueError('If using all scalar values, you must pass' 6203 ' an index') 6204
ValueError: If using all scalar values, you must pass an index
Read DataFrame defaultdict(<class 'list'>, {'NoT/machinename': MachineName MachineType SensorWorking \
This is the code im running :
client = DataFrameClient(host, port, user, password, dbname)
print("Read DataFrame")
AandCStation = client.query("""SELECT * FROM "NoT/machinename" WHERE time >= now() - 12h""")
print(AandCStation)
print(type(AandCStation))
df = pd.DataFrame(AandCStation)
This is the data:
Read DataFrame
defaultdict(<class 'list'>, {'NoT/sensor': MachineName MachineType SensorWorking \
2018-07-16 04:11:19.912895848+00:00 Quench tank Yes
2018-07-16 04:11:22.961838564+00:00 Quench tank Yes
2018-07-16 04:11:25.872680626+00:00 Quench tank Yes
2018-07-16 04:11:28.850205591+00:00 Quench tank Yes
... ... ... ...
2018-07-16 16:08:05.188868516+00:00 Quench tank Yes
2018-07-16 16:08:08.169862344+00:00 Quench tank Yes
2018-07-16 16:08:11.144413930+00:00 Quench tank Yes
2018-07-16 16:08:14.126290232+00:00 Quench tank Yes
2018-07-16 16:08:17.107127232+00:00 Quench tank Yes
2018-07-16 16:08:20.079248843+00:00 Quench tank Yes
TempValue
2018-07-16 04:09:50.467145647+00:00 32.69
2018-07-16 04:09:53.888973858+00:00 32.69
2018-07-16 04:09:55.879811649+00:00 32.69
2018-07-16 04:09:58.818001127+00:00 32.69
... ...
2018-07-16 16:08:05.188868516+00:00 34.19
2018-07-16 16:08:08.169862344+00:00 34.19
2018-07-16 16:09:43.209347998+00:00 34.19
2018-07-16 16:09:46.187872612+00:00 34.19
[12233 rows x 4 columns]})
<class 'collections.defaultdict'>
Any ideas why im getting the error?
I came across this same issue today.
So it turns out that you are getting a dictionary of DataFrames which you can concat and then droplevel to have the desired columns.
client = DataFrameClient(host, port, user, password, dbname)
print("Read DataFrame")
AandCStation = client.query("""SELECT * FROM "NoT/machinename" WHERE time >= now() - 12h""")
AandCStation = pd.concat(AandCStation, axis=1)
AandCStation.columns = AandCStation.columns.droplevel()
print(AandCStation.head())
print(type(AandCStation))
Hope this helps!
Sources: