Creating a List of Empty Lists
michael at foord.net
Thu Dec 4 15:49:11 CET 2003
Pythons internal 'pointers' system is certainly causing me a few
headaches..... When I want to copy the contents of a variable I find
it impossible to know whether I've copied the contents *or* just
created a new pointer to the original value....
For example I wanted to initialize a list of empty lists....
a=[ , , , ,  ]
I thought there has to be a *really* easy way of doing it - after a
bit of hacking I discovered that :
a = []*10 appeared to work
however - using it in my program called bizarre crashes....
I eventually discovered that (as a silly example) :
a = []*10
while b < 10:
b += 1
a[b] = b
[ , , ......
Which isn't at all what I intended...............
What is the correct, quick way of doing this (without using a loop and
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