[Tutor] lambda and map

[Pedro Diaz Jimenez]

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Thats because map needs a funcition, like reduce or filter. lambda functions 
are the fast food of programming: not much content, but you can use it 
inmediatlly

say you wanna filter [1,2,3,4,5,6] taking away the odd numbers
if you don't use lambda, you have to
def isOdd(n):
	blah
	blah

filter( isOdd, [1,2,3,4,5] );

With lambda calculus, is just:
>>> filter( lambda x: (x%2)==0, [1,2,3,4,5,6] )
[2, 4, 6]
>>>

voila!

Cheers
Pedro

On Saturday 26 May 2001 22:13, Timothy M. Brauch wrote:
> Okay, I am now what I would call competent in Python.  But, I keep
> noticing (learning) some new stuff every time I get an email from
> tutor.  There is, however, one thing I am not really sure about,
> lambda.  I don't quite understand what a lambda does or why to use it.
> I think I understand map, more or less, but the two are often seen
> together.
>
>  - Tim
>
> _______________________________________________
> Tutor maillist  -  Tutor@python.org
> http://mail.python.org/mailman/listinfo/tutor

- -- 

/*
 * Pedro Diaz Jimenez
 * pdiaz88@terra.es 
 * pdiaz@acm.asoc.fi.upm.es
 *
 * Wanna see how 100000! looks like?:
 * http://acm.asoc.fi.upm.es/~pdiaz/fact_100.000
 * 
 * La sabiduria me persigue, pero yo soy mas rapido
 *
 */

Random quote:
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