Can't reset board after a number of tries.

[chimosky]

After making a calculation and trying to reset the abacus board, the reset button has no effect and this is shown in the logs.
Noticed after a couple of tries.

Traceback (most recent call last):
  File "/home/ibiam/Activities/activity-abacus/abacus_window.py", line 939, in _keypress_cb
    self._process_numeric_input(self.last, k)
  File "/home/ibiam/Activities/activity-abacus/abacus_window.py", line 981, in _process_numeric_input
    float(newnum.replace(self.decimal_point, '.')))
ValueError: could not convert string to float: 

[chimosky]

@AbhijeetFasate13 Feel free to work on the issue and open a PR, you should take a looking at our contributing-how-to if you haven't.

[jriyyya]

Hey @chimosky, I tried to reproduce this bug, but wasn't able to, did you notice any other pattern around or maybe remember which abacus board you were testing

[quozl]

The message can be reproduced by clicking above the abacus then pressing the Return key. The issue described may have been fixed in the latest commit. Perhaps the message and the issue are decoupled and coincident.