Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.python > #24852 > unrolled thread
| Started by | Mark Lawrence <breamoreboy@yahoo.co.uk> |
|---|---|
| First post | 2012-07-04 09:24 +0100 |
| Last post | 2012-07-04 09:24 +0100 |
| Articles | 1 — 1 participant |
Back to article view | Back to comp.lang.python
This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by
below is the oldest one visible, not the original post.
Re: a problem about "print" Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-07-04 09:24 +0100
| From | Mark Lawrence <breamoreboy@yahoo.co.uk> |
|---|---|
| Date | 2012-07-04 09:24 +0100 |
| Subject | Re: a problem about "print" |
| Message-ID | <mailman.1784.1341390234.4697.python-list@python.org> |
@Matteo, @Levi, please don't top post it makes following a thread very difficult, no other comments, TIA. On 04/07/2012 08:51, Matteo Boscolo wrote: > in the code2 > > aList=[1,2,3,4,5,6,7,8,9,10] > aList=str(aList) #<--- here you convert the list in a string > > print aList > print aList[2] #<-- here you are printing the third caracter of the > string '[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]' not the list '[1, 2, 3, 4, 5, > 6, 7, 8, 9, 10]' > > regards > Matteo > > > > Il 04/07/2012 09:28, levi nie ha scritto: >> Hi,Harrison. >> Your method is cool. >> But i doubt this, if bList and aList just are attached to the same >> List when i write bList=aList,but why the output of the following two >> code are different? >> >> code1: >> aList=[1,2,3,4,5,6,7,8,9,10] >> bList=aList >> bList=str(bList) >> print aList >> print aList[2] >> >> code2: >> aList=[1,2,3,4,5,6,7,8,9,10] >> aList=str(aList) >> print aList >> print aList[2] >> >> i'm puzzled now. >> >> 2012/7/4 Harrison Morgan <harrison.morgan@gmail.com >> <mailto:harrison.morgan@gmail.com>> >> >> >> >> On Wed, Jul 4, 2012 at 12:38 AM, levi nie <levinie001@gmail.com >> <mailto:levinie001@gmail.com>> wrote: >> >> that's good,thanks. >> new problem. >> when i write >> bList=aList >> del bList[2] >> bList and aList both change,how can i make aList not changed? >> >> >> >> Lists are mutable. That means that when you do bList = aList, >> you're just creating another reference to aList. They both point >> to the same list, just using different names. You should read up a >> bit on immutable vs. mutable objects. Here's something that I >> found that might explain it a bit better. >> http://henry.precheur.org/python/copy_list >> >> >> >> > > > > > -- Cheers. Mark Lawrence.
Back to top | Article view | comp.lang.python
csiph-web