9.8.1 Division by Zero and Invalid Input

Division By Zero

Recall that attempting to divide by 0 results in a ZeroDivisionError:

In [1]:
10 / 0 

------------------------------------------------------------------------
ZeroDivisionError                      Traceback (most recent call last)
<ipython-input-1-a243dfbf119d> in <module>
----> 1 10 / 0

ZeroDivisionError: division by zero
  • Interpreter raises an exception of type ZeroDivisionError
  • Exception in IPython
    • terminates the snippet,
    • displays the exception’s traceback, then
    • shows the next In [] prompt so you can input the next snippet
  • Exception in a script terminates it and IPython displays the traceback

Invalid Input

  • int raises a ValueError if you attempt to convert to an integer a string (like 'hello') that does not represent a number
In [2]:
value = int(input('Enter an integer: '))

------------------------------------------------------------------------
ValueError                             Traceback (most recent call last)
<ipython-input-2-b521605464d6> in <module>
----> 1 value = int(input('Enter an integer: '))

ValueError: invalid literal for int() with base 10: 'hello'

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