aList = [123, 'xyz', 'zara', 'abc']
aList.append(2014)
print aList
which produces o/p [123, 'xyz', 'zara', 'abc', 2014]
What should be done to overwrite/update this list. I want the o/p to be
[2014, 'xyz', 'zara', 'abc']
This question is related to
python
list
overriding
overwrite
You may try this
alist[0] = 2014
but if you are not sure about the position of 123 then you may try like this:
for idx, item in enumerate(alist):
if 123 in item:
alist[idx] = 2014
I'm learning to code and I found this same problem. I believe the easier way to solve this is literaly overwriting the list like @kerby82 said:
An item in a list in Python can be set to a value using the form
x[n] = v
Where x is the name of the list, n is the index in the array and v is the value you want to set.
In your exemple:
aList = [123, 'xyz', 'zara', 'abc']
aList[0] = 2014
print aList
>>[2014, 'xyz', 'zara', 'abc']
I would prefer it without enumerate and instead use "range" like this:
for item in range(0, len(alist)):
if 123 in alist[item]:
alist[item] = 2014
For those who are new to python it might be more readable and a little smarter to recap.
Regards P.
If you are trying to take a value from the same array and trying to update it, you can use the following code.
{ 'condition': {
'ts': [ '5a81625ba0ff65023c729022',
'5a8161ada0ff65023c728f51',
'5a815fb4a0ff65023c728dcd']}
If the collection is userData['condition']['ts'] and we need to
for i,supplier in enumerate(userData['condition']['ts']):
supplier = ObjectId(supplier)
userData['condition']['ts'][i] = supplier
The output will be
{'condition': { 'ts': [ ObjectId('5a81625ba0ff65023c729022'),
ObjectId('5a8161ada0ff65023c728f51'),
ObjectId('5a815fb4a0ff65023c728dcd')]}
What about replace the item if you know the position:
aList[0]=2014
Or if you don't know the position loop in the list, find the item and then replace it
aList = [123, 'xyz', 'zara', 'abc']
for i,item in enumerate(aList):
if item==123:
aList[i]=2014
break
print aList
I think it is more pythonic:
aList.remove(123)
aList.insert(0, 2014)
more useful:
def shuffle(list, to_delete, to_shuffle, index):
list.remove(to_delete)
list.insert(index, to_shuffle)
return
list = ['a', 'b']
shuffle(list, 'a', 'c', 0)
print list
>> ['c', 'b']
Source: Stackoverflow.com