using "*" to make a list of lists with repeated (and independent) elements
88888 Dihedral
dihedral88888 at googlemail.com
Wed Sep 26 18:28:15 EDT 2012
88888 Dihedral於 2012年9月27日星期四UTC+8上午6時07分35秒寫道:
> Paul Rubin於 2012年9月27日星期四UTC+8上午5時43分58秒寫道:
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> > TP <TP at frenoespam.fr.invalid> writes:
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> > > copies a list, he copies in fact the *pointer* to the list ....
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> > > Is it the correct explanation?
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> > Yes, that is correct.
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> > > In these conditions, how to make this list [[0,0,0],[0,0,0]] with "*"
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> > > without this behavior?
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> > >>> a = [[0]*3 for i in xrange(2)]
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> > >>> a[0][0]=2
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> > >>> a
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> > [[2, 0, 0], [0, 0, 0]]
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> I used numpy before.
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> Python is not lisp but python can emulate the lisp behaviors.
def zeros(m,n):
a=[]
for i in xrange(m):
a.append([0]*n)
return a
If one wants to tranlate to C, this is the style.
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