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Python 2.0 and teaching precalculus

Kirby Urner urner at alumni.princeton.edu
Sun Sep 10 12:10:05 EDT 2000 
Kirby Urner <urner at alumni.princeton.edu> wrote:

>Erik Max Francis <max at alcyone.com> wrote:
>
>>Kirby Urner wrote:
>>
>>> def wiggle(function,input,epsilon=1e-10):
>>>     """
>>>     Accepts a function, value and returns delta f / delta x
>>>     for small epsilon (default of 1^-10 may be overridden)
>>	...
>>
>>1 seems like a bad choice for an epsilon ... :-)
>
>Woops. 
>
>Thanks for pointing out the typo.  Fixed it at the source 
>page: http://www.ineterena.com/~pdx4d/ocn/precalc.html 
>
>Of course it's all relative.  1 is really small if your 
>x's are 10,000,000,000 apart :-D
>
>Kirby

==================
Actually, it was already OK on the web version, but your quick
detection of the goof prompted me to follow up on edu-sig:

 >Here's wiggle():
 >
 >def wiggle(function,input,epsilon=1e-10):
 >    """
 >    Accepts a function, value and returns delta f / delta x
 >    for small epsilon (default of 1^-10 may be overridden)
 >    """    
 >    return (function(input+epsilon) - function(input))/epsilon

Fast reader on comp.lang.python caught the above typo error 
in my post (web version was OK).

Of course 1^-10 is simply 1.  Now that I stop to cogitate, 
I see this could be a real confusion. 1e-10 = 10^-10, just 
as 1e2 = 10^2 = 100.  Need to remind students that #.###e### 
means #.### x 10**###, obviously not #.###**###.

Kirby
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