CODEWITHSUNDEEP
pythonpython-3.xspyder
314mip
314mip

Reputation: 403

Error in Python: name 'df' is not defined

Im new in python, many hours googled and search here in stackoverflow. But still have problem with my code. I need run foo function in time interval, and fill dataframe (eg every second add timestamp to df). I'm still coming across a error message: NameError: name 'df' is not defined

Thank you for your answer.

Code:

    WAIT_TIME_SECONDS = 1


class ProgramKilled(Exception):
    pass

    df = pd.DataFrame([])

############################################################
############################################################
def foo():

    global df
    time1 = str(datetime.now())
    time2 = time1.replace(":", "_")
    print(time2)

    df2 = pd.DataFrame(data= {
    'timestamp': [time2],
    'cas_zapas_1_text': ['cas']
    })

    df = df.append(df2)

############################################################
############################################################
def signal_handler(signum, frame):
    raise ProgramKilled

class Job(threading.Thread):
    def __init__(self, interval, execute, *args, **kwargs):
        threading.Thread.__init__(self)
        self.daemon = False
        self.stopped = threading.Event()
        self.interval = interval
        self.execute = execute
        self.args = args
        self.kwargs = kwargs

    def stop(self):
                self.stopped.set()
                self.join()
    def run(self):
            while not self.stopped.wait(self.interval.total_seconds()):
                self.execute(*self.args, **self.kwargs)

if __name__ == "__main__":
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGINT, signal_handler)
    job = Job(interval=timedelta(seconds=WAIT_TIME_SECONDS), execute=foo)
    job.start()

    while True:
          try:
              time.sleep(1)
          except ProgramKilled:
              print("Program killed: running cleanup code")
              job.stop()
              break

This is resultof script:

runfile('C:/Users/Miro/.spyder-py3/untitled8.py', wdir='C:/Users/Miro/.spyder-py3')
Exception in thread Thread-8:
Traceback (most recent call last):
  File "C:\Users\Miro\Anaconda3\envs\spyder_4_0_1\lib\threading.py", line 932, in _bootstrap_inner
    self.run()
  File "C:\Users\Miro\.spyder-py3\untitled8.py", line 90, in run
    self.execute(*self.args, **self.kwargs)
  File "C:\Users\Miro\.spyder-py3\untitled8.py", line 68, in foo
    df = df.append(df2)
NameError: name 'df' is not defined
2020-06-16 08_29_31.920157
Program killed: running cleanup code

Upvotes: 0

Views: 19840

Answers (4)

314mip
314mip

Reputation: 403

Thank you all for your helpful and quick answers. This solution works:

    WAIT_TIME_SECONDS = 1

global df
df = pd.DataFrame([])

class ProgramKilled(Exception):
    pass



############################################################
############################################################
def foo():

    global df
    time1 = str(datetime.now())
    time2 = time1.replace(":", "_")
    print(time2)

    df2 = pd.DataFrame(data= {
    'timestamp': [time2],
    'cas_zapas_1_text': ['cas']
    })

    df = df.append(df2)

############################################################
############################################################
def signal_handler(signum, frame):
    raise ProgramKilled

class Job(threading.Thread):
    def __init__(self, interval, execute, *args, **kwargs):
        threading.Thread.__init__(self)
        self.daemon = False
        self.stopped = threading.Event()
        self.interval = interval
        self.execute = execute
        self.args = args
        self.kwargs = kwargs

    def stop(self):
                self.stopped.set()
                self.join()
    def run(self):
            while not self.stopped.wait(self.interval.total_seconds()):
                self.execute(*self.args, **self.kwargs)

if __name__ == "__main__":
    signal.signal(signal.SIGTERM, signal_handler)
    signal.signal(signal.SIGINT, signal_handler)
    job = Job(interval=timedelta(seconds=WAIT_TIME_SECONDS), execute=foo)
    job.start()

    while True:
          try:
              time.sleep(1)
          except ProgramKilled:
              print("Program killed: running cleanup code")
              job.stop()
              break

Upvotes: 0

tdelaney
tdelaney

Reputation: 77347

You made df part of the ProgramKilled class namespace. Just dedent it and it becomes a module level variable. Functions that want to assign it later use global df - but you're already doing that part correctly in your code.

Just change to

class ProgramKilled(Exception):
    pass

df = pd.DataFrame([])

Upvotes: 0

Osadhi Virochana
Osadhi Virochana

Reputation: 1302

Define global df before class ProgramKilled(Exception):

Upvotes: 1

Jason Yang
Jason Yang

Reputation: 13061

It means df is a class variable and not work.

class ProgramKilled(Exception):
    pass

    df = pd.DataFrame([])

If not a class variable, you should change it as following

class ProgramKilled(Exception):
    pass
...
if __name__ == "__main__":
...
df = pd.DataFrame([])
...

If you need to define it there, I think it's not a good choice.

class ProgramKilled(Exception):
    global df
    df = pd.DataFrame([])
    pass

Upvotes: 0

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