Weewx fails to start

[Ron Walker]

Hi All,

I am using weewx 3.9.1 on a Raspberry pi.  Up until yesterday, the system was running fine.  I had stopped the pi yesterday to move it to a new location.  Today when I attempted to start the program, I get the following error and then it quits.  Any help pointing me in the right direction to a resolution would be greatly appreciated!

Error output:

Traceback (most recent call last):

  File "/usr/bin/weewxd", line 64, in <module>

    weewx.engine.main(options, args)

  File "/usr/share/weewx/weewx/engine.py", line 890, in main

    engine.run()

  File "/usr/share/weewx/weewx/engine.py", line 191, in run

    self.dispatchEvent(weewx.Event(weewx.NEW_LOOP_PACKET, packet=packet))

  File "/usr/share/weewx/weewx/engine.py", line 224, in dispatchEvent

    callback(event)

  File "/usr/share/weewx/weewx/engine.py", line 546, in new_loop_packet

    self.accumulator.addRecord(event.packet, add_hilo=self.loop_hilo)

  File "/usr/share/weewx/weewx/accum.py", line 256, in addRecord

    func(self, record, obs_type, add_hilo, weight)

  File "/usr/share/weewx/weewx/accum.py", line 315, in add_value

    self[obs_type].addSum(val, weight=weight)

  File "/usr/share/weewx/weewx/accum.py", line 93, in addSum

    raise ValueError("accum: ScalarStats.addSum expected float or int, got %s" % val)

ValueError: accum: ScalarStats.addSum expected float or int, got nan

Thanks in advance!! 

[Tom Keffer]

You're not giving us a lot of information about your system. 

In Python, a 'nan' ("not a number") is not returned by any function unless one of the inputs to the function is a nan. That means one of your sensors probably emitted a 'nan', either directly as a value (unlikely), or by emitting a string with the literal characters 'nan'. 

But, again, it's impossible to say anything without knowing more about your system.

I will add one thing: V4.x includes a protection against ingesting nans. Good reason to upgrade.

-tk

--
You received this message because you are subscribed to the Google Groups "weewx-user" group.
To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/weewx-user/3da3a69c-7e1a-4a86-ae97-6b86adc7f028o%40googlegroups.com.

[Ron Walker]

Thanks for your reply.  The weather station consists of an arduino microcontroller reading sensors and sending data to the pi, which places it in a CSV file.  I'm using fileparse in weewx to read the file.  You were correct in your assessment!  I looked through the CSV file and found entries with a 'nan' value for my second temperature sensor, which was bad!  Replacing the sensor resolved the issue.

For future reference, what information should I include in a post like this?

Thanks again!

On Thursday, June 25, 2020 at 4:53:39 PM UTC-4, Ron Walker wrote:

Hi All,

I am using weewx 3.9.1 on a Raspberry pi.  Up until yesterday, the system was running fine.  I had stopped the pi yesterday to move it to a new location.  Today when I attempted to start the program, I get the following error and then it quits.  Any help pointing me in the right direction to a resolution would be greatly appreciated!

Error output:.