Welcome!
This is the community forum for my apps Pythonista and Editorial.
For individual support questions, you can also send an email. If you have a very short question or just want to say hello — I'm @olemoritz on Twitter.
Problems with Matplotlib
-
I am trying to plot some data from an SQLITE db and I am having a problem with the data conversion:
import sqlite3 import time import datetime import numpy as np import matplotlib.pyplot as plt import matplotlib.dates as mdates conn = sqlite3.connect('acurite.sqlite') c = conn.cursor() sql = "SELECT * FROM acuriteHx" graphArray = [] for row in c.execute(sql): startingInfo = str(row).replace(')','').replace('(','').replace('u\'','').replace("'","") splitInfo = startingInfo.split(',') graphArrayAppend = splitInfo[0] + ',' + splitInfo[2] graphArray.append(graphArrayAppend) #print(graphArray) datestamp, value = np.loadtxt(graphArray,delimiter=',', unpack=True, converters={ 0: mdates.datestr2num('%Y-%m-%d %H:%M:%S')}) fig = plt.figure() rect = fig.patch sax1 = fig.add_subplot(1,1,1, axisbg='white') plt.plot_date(x=datestamp, y=value, fmt='b-', label = 'value', linewidth=2) plt.show() ``` When run with Python2.7 it crashes Pythonista and when run with Python3 it gives: Traceback (most recent call last): File "/private/var/mobile/Containers/Shared/AppGroup/4F06F35D-865B-4115-B827-BA053B3731EF/Pythonista3/Documents/sqliteplot.py", line 22, in <module> converters={ 0: mdates.datestr2num('%Y-%m-%d %H:%M:%S')}) File "/var/containers/Bundle/Application/D78A900B-1E3B-4075-9CAB-F95408B28CD2/Pythonista3.app/Frameworks/Py3Kit.framework/pylib/site-packages/matplotlib/dates.py", line 283, in datestr2num dt = dateutil.parser.parse(d, default=default) File "/var/containers/Bundle/Application/D78A900B-1E3B-4075-9CAB-F95408B28CD2/Pythonista3.app/Frameworks/Py3Kit.framework/pylib/site-packages/dateutil/parser.py", line 749, in parse return DEFAULTPARSER.parse(timestr, **kwargs) File "/var/containers/Bundle/Application/D78A900B-1E3B-4075-9CAB-F95408B28CD2/Pythonista3.app/Frameworks/Py3Kit.framework/pylib/site-packages/dateutil/parser.py", line 311, in parse res, skipped_tokens = self._parse(timestr, **kwargs) TypeError: 'NoneType' object is not iterable