[Tutor] packing a list of lists

[kevin parks]

Interestingly changing:
		out_list.append(ll)

to

		out_list.append(list(ll))


seems to work. The part of my brain that understood why that is must  
have sleeping.

-k


On Aug 28, 2009, at 11:05 PM, i wrote:

> Back to python after a long long layoff. So i am running into some  
> beginner's confusion...
>
> I am trying to plot a list of numbers in gnuplot.py. To do that I am  
> trying to pack the list with an index by iterating over the list so  
> i can get something like:
>
> foo = [12, 11, 9, 6, 2, 9, 3, 8, 12, 3, 5, 6]
>
> [ [1, 12], [2, 11], [3, 9], [4, 6], [5, 2], [6, 9], [7, 3], [8,  
> 8] ... ]
>
> So that i have x, y pairs to plot. When i print in my func i get the  
> right thing, for each item (note scaffolding) yet when i reurn the  
> whole list i just get the last pair repeated over and over.
>
> I am not sure why this is.
>
>
> def pack(in_seq):
> 	out_list=[]
> 	x = 1
> 	ll=[1, 1]
> 	for each in in_seq:
> 		ll[0] = x
> 		ll[1] = each
> 		out_list.append(ll)
> 		#print ll
> 		x = x + 1
> 	print out_list
> 		
>
> # function declarations would go here
> def test():
> 	"""test function - say what this does here and skip a line
> 	
> 	Keyword arguments:
> 	none
> 	"""
>
> 	print
> 	foo = minus(200)
> 	plot_me = pack(foo)
> 	#print foo
> 	print
> 	print plot_me
> 	
>
> if __name__ == "__main__":
> 	test()
>
>