Underlying datastructure of list, tuple, dict [closed] - python

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 8 years ago.
Improve this question
I would like to get some understanding on how the data types in python - list, tuple, dict and set - are implemented
How are they implemented, importantly the data structure used.
Any place/ url to precisely get this understanding?

The best place to look is the CPython implementation source code:
dict - Hash map targeting fast resolution of keys
list - Looks like an array of PyObjects
tuple - Same as list but with optimisations that a tuple can allow (fixed size, objects)
set - Hash map with optimisations for cache locality
The source code is heavily commented and well written C. This would be the best place to understand the data structures used in detail.

Related

Is there a linked list predefined library in Python? [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking for code must demonstrate a minimal understanding of the problem being solved. Include attempted solutions, why they didn't work, and the expected results. See also: Stack Overflow question checklist
Closed 9 years ago.
The community reviewed whether to reopen this question last year and left it closed:
Duplicate This question has been answered, is not unique, and doesn’t differentiate itself from another question.
Improve this question
I know in c++ it already exist
#include <list>
Now I am curious to know if it exist in python also.
You can also take a look at llist python package, which provides some useful features that deque does not. There are not only doubly linked lists, but also single linked lists data structure in that package. IMHO, one of the biggest advantages of this package is the ability to store a reference to the llist elements.
It appears that collections.deque is a doubly-linked-list library in Python. According to the documentation, it should have approximately O(1) cost when appending or popping from the head or the tail, as well as O(n) for regular inserts (which matches what we'd expect from a linked list).
API: http://docs.python.org/2/library/collections.html#collections.deque
Source: https://stackoverflow.com/a/282238/2441252

Cash flow diagram in python [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 9 years ago.
Improve this question
I need to make a very simple image that will illustrate a cash flow diagram based on user input. Basically, I just need to make an axis and some arrows facing up and down and proportional to the value of the cash flow. I would like to know how to do this with matplot.
The best tool can be matplotlib. You can simply store the values in a list and then use 'stem' to draw the lines. Then you can use markers with triangle_up and triangle_down to show the arrow.
If you simply need arrows pointing up and down, use Unicode arrows like "↑" and "↓". This would be really simple if rendering in a browser.

How to edit a database in Python? [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 9 years ago.
Improve this question
I am an absolute beginner in Python (3.3.2). I know the basic functions like writing text files, variables, loops ,etc but have never written complex code.
My research project requires applying a moving average filter on three columns of a large text file (150 MB in size, having more than 1 million rows). My question is: What should I study in order to develop a methodology to apply the moving average formula within Python?. Excel is not an option because doing so is very tedious in Excel and sometimes it crashes due to longer periods of loading.
Kindly direct me to the 'right' resources/ examples relevant to my problem. I have gone through several python tutorials but didn't find anything relevant.
Check out Pandas. It should have no problem handling 10**6 rows on commonly available modern hardware. And among its many goodies are functions for computing moving averages.

Python cheatsheet for beginners? [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 9 years ago.
Improve this question
I've seen the cheatsheet floating around the web, but I'm after something that shows assigning variables; creating literals, tuple, lists, dictionaries, sets; accessing lists, disctionaries; list of operators; list of datatype functions etc..
..so something that I memorize and remember easily.
Thanks!
You can use the Python Quick Reference (PQR), latest versions available from http://rgruet.free.fr/. It is updated for each new version by different people.

difflib on Ruby [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a book, tool, software library, tutorial or other off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 8 years ago.
Improve this question
Is there a library similar to Python's difflib on Ruby?
Particularly, I need one that has a method similar to difflib.get_close_matches. Any recommendations?
After some research, I suggest using amatch or SimMetrics (with JRuby) and manually implement the get_close_matches method. Both libs offer implementations of many string similarity algorithms.
You can take a look at diff-lcs.

Categories

Resources