wflogger.py unsupported operand types

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Start wflogger

What is the expected output? What do you see instead?
Expected events to be logged to wfrog.csv

What happens instead: nothing logged to wfrog.csv. 
wflogger.log is full of same error:

2012-02-07 19:26:22,431 ERROR [wflogger] Could not send event to 
<wfcommon.generic.YamlMultiElement object at 0x40d33a30>
Traceback (most recent call last):
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/wflogger.py", line 127, in output_loop
    self.collector.send_event(event, context=context)
  File "/share/MD0_DATA/.qpkg/wfrog/wfcommon/generic/multi.py", line 62, in _call
    result[name] = r.__getattribute__(attr).__call__(*args, **keywords)
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/buffer.py", line 99, in send_event
    self.forward_event(event_to_send, context)
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/buffer.py", line 133, in forward_event
    self.do_send(flush_event, context)
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/buffer.py", line 139, in do_send
    self.collector.send_event(event, context)
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/base.py", line 47, in send_event
    self.flush(context)
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/aggregator.py", line 179, in flush
    sample = self.get_data()
  File "/share/MD0_DATA/.qpkg/wfrog/wflogger/collector/aggregator.py", line 123, in get_data
    data['temp'] = round(sum(self._temp)/len(self._temp), 1)
TypeError: unsupported operand type(s) for +: 'float' and 'NoneType'

What version of the product are you using? On what operating system?
wfrog: 0.8.1
OS: QNAP TS-209
Station: Fine Offset WH3081
driver: wh1080

Please provide any additional information below.

Original issue reported on code.google.com by warren.c...@gmail.com on 7 Feb 2012 at 8:40

[GoogleCodeExporter]

Also the same error with driver wh1080.py 
Station: Fine Offset WH1080
lubuntu 11.10 on eeepc701
writing to firebird2.5 database
python2.6 with also python2.7

/var/log/wfrog.log
2012-02-17 15:51:37,062 ERROR [wflogger] Could not send event to 
<wfcommon.generic.YamlMultiElement object at 0x9661f6c>
Traceback (most recent call last):
  File "/usr/lib/wfrog/wflogger/wflogger.py", line 127, in output_loop
    self.collector.send_event(event, context=context)
  File "/usr/lib/wfrog/wfcommon/generic/multi.py", line 62, in _call
    result[name] = r.__getattribute__(attr).__call__(*args, **keywords)
  File "/usr/lib/wfrog/wflogger/collector/buffer.py", line 99, in send_event
    self.forward_event(event_to_send, context)
  File "/usr/lib/wfrog/wflogger/collector/buffer.py", line 133, in forward_event
    self.do_send(flush_event, context)
  File "/usr/lib/wfrog/wflogger/collector/buffer.py", line 139, in do_send
    self.collector.send_event(event, context)
  File "/usr/lib/wfrog/wflogger/collector/base.py", line 47, in send_event
    self.flush(context)
  File "/usr/lib/wfrog/wflogger/collector/aggregator.py", line 179, in flush
    sample = self.get_data()
  File "/usr/lib/wfrog/wflogger/collector/aggregator.py", line 123, in get_data
    data['temp'] = round(sum(self._temp)/len(self._temp), 1)
TypeError: unsupported operand type(s) for +: 'float' and 'NoneType'

Original comment by duinzi...@gmail.com on 17 Feb 2012 at 7:58