How do you change certain elements in a list? I'm looking to do the
Python equivalent of this Ruby code:
- first = [1, 2]
= [1, 2]
- second = first
= [1, 2]
- first.map! {|i| i + 1}
= [2, 3]
- first
= [2, 3]
- second
= [2, 3]
I need to change a list, in place, so other variables referencing that
list also see the change.
Thank you...
3  2422 
On Nov 6, 3:11 pm, "Just Another Victim of the Ambient Morality"
<ihates...@hotmail.comwrote:
How do you change certain elements in a list? I'm looking to do the
Python equivalent of this Ruby code:
- first = [1, 2]
= [1, 2]
- second = first
= [1, 2]
- first.map! {|i| i + 1}
= [2, 3]
- first
= [2, 3]
- second
= [2, 3]
I need to change a list, in place, so other variables referencing that
list also see the change.
Thank you...
You can "point" one variable name at another so that they both
reference the same list:
second = first
To change a list "in place", I usually do something like this:
first[someElement] = something-else
or
# change the first element in the list
first[0] = 55
See also http://docs.python.org/tut/node7.html http://www.diveintopython.org/native...pes/lists.html http://docs.python.org/lib/built-in-funcs.html
Mike
On Nov 6, 4:11 pm, "Just Another Victim of the Ambient Morality"
<ihates...@hotmail.comwrote:
How do you change certain elements in a list? I'm looking to do the
Python equivalent of this Ruby code:
- first = [1, 2]
= [1, 2]
- second = first
= [1, 2]
- first.map! {|i| i + 1}
= [2, 3]
- first
= [2, 3]
- second
= [2, 3]
I need to change a list, in place, so other variables referencing that
list also see the change.
Thank you...
>>first = [1,2]
second = first
for i in range(len(first)):
first[i] += 1
>>first
[2, 3]
>>second
[2, 3]
-Dan
Just Another Victim of the Ambient Morality a écrit :
How do you change certain elements in a list? I'm looking to do the
Python equivalent of this Ruby code:
- first = [1, 2]
= [1, 2]
- second = first
= [1, 2]
- first.map! {|i| i + 1}
= [2, 3]
- first
= [2, 3]
- second
= [2, 3]
I need to change a list, in place, so other variables referencing that
list also see the change.
first = [1,2]
second = first
first[:] = [i+1 for i in first]
HTH This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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