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: > > > TP <t...@frenoespam.fr.invalid> writes: > > > > > > > copies a list, he copies in fact the *pointer* to the list .... > > > > > > > Is it the correct explanation? > > > > > > > > > > > > Yes, that is correct. > > > > > > > > > > > > > In these conditions, how to make this list [[0,0,0],[0,0,0]] with "*" > > > > > > > without this behavior? > > > > > > > > > > > > >>> a = [[0]*3 for i in xrange(2)] > > > > > > >>> a[0][0]=2 > > > > > > >>> a > > > > > > [[2, 0, 0], [0, 0, 0]] > > > > I used numpy before. > > > > 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. -- http://mail.python.org/mailman/listinfo/python-list