Python data structure where largest element is always kept first [duplicate] - python

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Does python have a sorted list?
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What do I use for a max-heap implementation in Python?
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Closed 6 months ago.
I need a data structure like a dict where I can insert elements with a key and then efficiently take out largest element by value when I need it.

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Closed 10 months ago.
I have problem with converting
[['a'],['b'],['c']] --> ['a','b','c']
it seems simple but I am struggling for hours...
You could use a list comprehension to do something as simple as
[element[0] for element in letters_list]
This remakes the list, extracting the 0-index element from each sublist

What does [[]] do ? [duplicate]

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I don't know python I am working through 'Exercises in Programming Style' and translating to javascript. I can understand most of the python but this line flabbergasts me .
# Let's use the first 25 entries for the top 25 words
data = data + [[]]*(25 - len(data))
some context: the challenge is to use self imposed memory limitations represented here by the data array. So here she just cleared out data that is no longer used to make room for the 25 most frequent word. What is she doing here ?

Append something into interior list within nested list [duplicate]

This question already has answers here:
How to insert into python nested list
(3 answers)
Closed 5 years ago.
so I have a nested list like this:
nested list=[['Bike No.,Purchase Date,Batt %,Last Maintenance,KM since Last'], ['T101,10/04/2016,55,10/01/2017,25.08'], ['T102,01/07/2016,10,15/05/2017,30.94'], ['T103,15/11/2016,94,13/06/2017,83.16'], ['T104,25/04/2017,58,10/01/2017,25.08'], ['T105,24/05/2017,5,20/06/2017,93.80']]
and I want to append another element into this list ['Bike No.,Purchase Date,Batt %,Last Maintenance,KM since Last'] ,how should I do it?
This list is originally created from a csv file and is split by its line followed by its elements
by coldspeed:
nested_list[0].append(...)

Finding clusters in a python list [duplicate]

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Detecting consecutive integers in a list [duplicate]
(8 answers)
Grouping / clustering numbers in Python
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Closed 6 years ago.
I have a sorted python list which looks like:
myList = [1,2,3,7,8,9,12,13,14,15]
The consecutive elements with difference 1 form the cluster. I need to dig these clusters out.
In the above example the clusters would be 1,2,3; 7,8,9; 12,13,14,15
Is there a way other than to write a for loop and see where the difference between consecutive elements is > 1
Edit: The list I have is large so I want to avoid using a for loop as much as I can unless that is the only way out

incrementing elements of 2d list in python [duplicate]

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Nested List Indices [duplicate]
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Closed 9 years ago.
I've noticed something strange when trying to implement elements of a 2d list in python. Here is my code
n_dk=2*[5*[0]]
n_dk[0][0]+=1
print n_dk
I would expect the output to be
[[1,0,0,0,0],[0,0,0,0,0]]
but the actual output is
[[1,0,0,0,0],[1,0,0,0,0]]
can anyone tell me what I am doing wrong. btw I used a numpy array instead and it worked the way I wanted it to.

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