Questions regarding efficient storing and representing data within a software application.

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0
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3answers
156 views

At what level of abstraction are data structured created?

I am learning about Linked List and Arrays in my data structures class. We are make them in Java. Are actual data structures designed in Java/C? Or are they made in lower level languages like ...
9
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3answers
842 views

Clean Code and Hybrid Objects and Feature Envy

So I recently made some major refactorings to my code. One of the main things I tried to do was split out my classes into data objects and worker objects. This was inspired, among other things, by ...
1
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3answers
239 views

Is there a programming pattern, design pattern, or naming convention for moving data between related schemas? [closed]

I'm working on a web application that is publicly accessible. (Really) Long story short, we have two sets of tables in the database with relatively the same names and relatively the same data. The ...
3
votes
3answers
444 views

Separating Code into Smaller Files in C

I am in the process of cleaning up my code and making it easier to maintain. I am doing this by turning my 5000+ line file into separate smaller files. I have successfully created separate source and ...
1
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4answers
480 views

How to work around Java's lack of pointers to pointers when working with linked data structures? [closed]

I've learned from a textbook how to implement binary search trees recursively in Java, and am working on implementing them nonrecursively. I've found a simple and elegant way to implement an insert ...
1
vote
1answer
170 views

How to efficiently sort a recursively defined Stack?

I am trying to implement a recursively defined Stack and sort it in Java. I don't have a particular usage of this program in mind. I found this approach of stack implementation a bit useful while ...
-2
votes
1answer
293 views

What is the largest size a HashSet or TreeSet be? [closed]

So I am working on a solo project that involves a lot of strings. In one of my smaller test cases there will be at least 70 million elements. So my question is, what is the largest possible size a ...
0
votes
1answer
470 views

Competitive Programming [closed]

I think this may just be one of the most frequently asked questions by a novice (like me) on this site. Please pardon me for that. My question is I wish to get better at solving the harder problems of ...
1
vote
4answers
139 views

Efficient “Object with weights” structure

I need to find an "efficient" data structure / set of algorithms to do the following things: I have a list of objects. I need to assign them weights and later on increase or decrease these weights. ...
1
vote
1answer
186 views

Automatic denormalization for a NoSQL database application

We have a use case where we store table-like data, but we know about the schema of the data only at runtime. In our application, a power user defines a schema and normal user can create records and ...
0
votes
0answers
107 views

Converting a huge decision tree into a decision list for fuzzy matching

I'm trying to build an intelligent action bar similar to the command palette of Sublime Text: The Sublime Text command palette allows fuzzy matching of commands in the list (e.g. "ancd vin" will ...
2
votes
1answer
51 views

I have an unordered list of rectangles and their neighbors on four sides with no origin. How can I efficiently convert this into a grid?

I am writing a GtkGrid-like container for my GUI library for Go, and I'm trying to write the actual layout part of the code. Basically, I have an unordered list of controls. Each control is a ...
3
votes
2answers
4k views

Difference between a heap and a priority queue

I always thought that heaps and priority queues were synonyms - an abstract data structure that supports the insert, findMin and deleteMin operations. Some literature seems to agree with me - Chris ...
1
vote
2answers
2k views

2D linked list vs. multidimensional array/vector

I hope that programmers is the correct stack exchange for this, as it is quite a concept based question. I'm working on a data structure in C++ that is a represents data in 3D space. The x-y plane is ...
2
votes
1answer
322 views

What is the “best practice” for converting an external API's data structure?

When an API's data structure does not fit well with an angular app, I am trying to determine the best-practice in my specific design and implementation for converting it to a usable structure. I was ...
2
votes
1answer
201 views

Tokenizing Text Held in a Rope Data Structure

I am building a text editor which makes use of a Ragel based tokenizer to support syntax highlighting. I am considering the use of a rope data structure to support efficient modifications and ...
5
votes
3answers
3k views

How exactly is an Abstract Syntax Tree created?

I think I understand the goal of an AST, and I've built a couple of tree structures before, but never an AST. I'm mostly confused because the nodes are text and not number, so I can't think of a nice ...
0
votes
1answer
108 views

How to make the members of my Data Access Layer object aware of their siblings

My team currently has a project with a data access object composed like so: public abstract class DataProvider { public CustomerRepository CustomerRepo { get; private set; } public ...
3
votes
2answers
199 views

Should I use nested matrices or dictionaries?

As per Should I ask my question about which data structure to use here? I'm asking this here. Hopefully this isn't too implementation specific. I'm currently developing a program that will represent ...
10
votes
2answers
745 views

How to represent a graph with multiple edges allowed between nodes and edges that can selectively disappear

I'm trying to figure out what sort of data structure to use for modeling some hypothetical, idealized network usage. In my scenario, a number of users who are hostile to each other are all trying to ...
3
votes
2answers
76 views

1 class model or 3 class models? 1 for each - UI, Hardware API Library, and Database

I've always used one class model in all 3 area's of my projects. User Interface, Hardware API (for data collection), Database (entity database context). Every new project only seems to grow in size, ...
5
votes
1answer
385 views

How to store satellite data in C data structures

I've been reading through Introduction To Algorithms 3rd Ed, and I am having difficulty in implementing some practical situations. It's not the theory, or implementing the internals of the data ...
0
votes
1answer
65 views

How to chain together points in an array

I have a series of points with lengths and rotations like this: I need to create separate chains from points whose lines overlap but I’m having real trouble doing this efficiently. I have an array ...
0
votes
3answers
260 views

Why is the complexity of fetching a value from an array be O(1)?

How come the complexity of fetching a value from an array by it's index is O(1)? I thought the algorithm has to go through all the indexes, find the correct index, and then know what value to return. ...
4
votes
2answers
388 views

Are bloom filters actually faster than hashes, even taking in account cache?

Bloom filters look really great when you consider you can determine if an Int is in a set with 99% certainty in constant time. But so can hashes, with the only difference that, in a hash, most of the ...
0
votes
2answers
264 views

boolean operations in C using bitfields

I am trying to implement boolean data type in C. Basically, I am working with sets. The following code can be used to access each bit but I am unsure whether I can represent sets using this method. ...
2
votes
1answer
232 views

How should data transfer between a client and a web API for normalized data be designed?

I want to design an API backed by some database (doesn't really matter which, but to make the discussion more interesting, let's say it's Mongo - explanation below) which sends data to a client. The ...
5
votes
2answers
382 views

Is it safe in Haskell to save a data structure to a file using “show”, and retrieve it using “read”?

Say I have the following types: type EndsTup = (Int,Int) -- (0-based index from start or end, Frequency) type FreqTup = (Char, [EndsTup], [EndsTup]) -- (Character, Freqs from start, Freqs ...
0
votes
3answers
2k views

Nested maps vs. combined keys

in the project I am currently working on we had three different types of prices depending on the age of the user (adult, child, etc...). So we had on the DB a table looking like this: PRICES type ...
4
votes
2answers
271 views

How can a true Vector be implemented in Haskell?

How could a true Vector type be implemented in Haskell? In order for something to be a Vector, it has to be stored sequentially in memory, with O(1) random access. But Haskell hides its memory ...
7
votes
1answer
212 views

Are “skip deltas” unique to svn?

The good folks who created the SVN version control system use a structure they refer to as "skip deltas" to store the revision history of files internally. A revision is stored as a delta against an ...
4
votes
3answers
3k views

Data Oriented Design - impractical with more than 1-2 structure “members”?

The usual example of Data Oriented Design is with the Ball structure: struct Ball { float Radius; float XYZ[3]; }; and then they make some algorithm that iterates a std::vector<Ball> ...
3
votes
1answer
399 views

Is using MultiMaps code smell? If so what alternative data structures fit my needs?

I'm trying to model nWoD characters for a roleplaying game in a character builder program. The crux is I want to support saving too and loading from yaml documents. One aspect of the character's is ...
2
votes
2answers
524 views

Best way of storing a small number of user credentials

I'm working on a messaging application, based on a server/client architecture. Now I am thinking about the way how to store the user credentials. It's not a huge number, just about 20 entries with ...
4
votes
4answers
284 views

Quadtree with duplicates

I'm implementing a quadtree. For those who don't know this data strucutre, I am including the following small description: A Quadtree is a data structure and is in the Euclidean plane what an ...
2
votes
2answers
378 views

How to present a stable data model in a public API that allows internal data structures to be changed without breaking the public view of the data?

I am in the process of developing an application that allows users to write C# scripts. These scripts allow users to call selected methods and to access and manipulate data in a document. This works ...
1
vote
3answers
497 views

Tournament bracket method to put distance between teammates

I am using a proper binary tree to simulate a tournament bracket. It's preferred any competitors in the bracket that are teammates don't meet each other until the later rounds. What is an efficient ...
0
votes
2answers
241 views

High-level strategy for distinguishing a regular string from invalid JSON (ie. JSON-like string detection)

Disclaimer On Absence of Code: I have no code to post because I haven't started writing; was looking for more theoretical guidance as I doubt I'll have trouble coding it but am pretty befuddled on ...
3
votes
2answers
541 views

Data structure for grid with negative indeces

Sorry if this is an insultingly obvious concept, but it's something I haven't done before and I've been unable to find any material discussing the best way to approach it. I'm wondering what's the ...
2
votes
1answer
393 views

Where to implement thread-safety logic for my queue data structure?

I will immediately confess that I do very little multithreading, so questions of style and organization in this domain a little fresh to me. I've written a data structure (in Python, if that matters) ...
0
votes
2answers
731 views

Exercise 3.6: Skiena Algorithm Design Manual

I am preparing for interview and try to solve the exercise problems of the book. 3-6. [5] Describe how to modify any balanced tree data structure such that search, insert, delete, minimum, and ...
2
votes
2answers
403 views

Most efficient way to store this collection of moduli and remainders?

I have a huge collection of different moduli and associated with each modulus a fairly large list of remainders. I want to store these values so that I can efficiently determine whether an integer is ...
1
vote
1answer
42 views

Benefits of caching the count of items in a data structure versus on-demand calculation?

Given a data structure, I want to provide an API method Size which returns the number of items. I am vacillating between 2 approaches: Maintain a count and increment/decrement it in response to ...
12
votes
2answers
3k views

What is the relationship between data structures and algorithms? [closed]

I have been searching for a good online course in data structures but have found that Google also returns results for algorithms courses, which say stuff like: In this course you will learn ...
5
votes
2answers
738 views

Overriding GetHashCode in a mutable struct - What NOT to do?

I am using the XNA Framework to make a learning project. It has a Point struct which exposes an X and Y value; for the purpose of optimization, it breaks the rules for proper struct design, since its ...
-1
votes
1answer
397 views

Does implementing algorithms improve your programming skills? [duplicate]

I have been self studying algorithms and data structures for some time now and currently enjoying it. Whenever I understand an algorithm, I usually try to code them from scratch for fun and I always ...
2
votes
2answers
329 views

Traversing an AST using Visitors

I'm writing a compiler for a C-like language, and I'm looking for an elegant way to traverse my abstract syntax tree. I'm trying to implement the Visitor pattern, although I'm not convinced that I'm ...
3
votes
6answers
2k views

How did programmers implement Linked list ideas before the object oriented paradigm?

Linked lists, as far as I have seen, are largely implemented using object-oriented ideas. (having an object that holds some information and the address of the next link). How were Linked-lists ...
1
vote
3answers
364 views

what is the javascript internal data structure?

Consider a basic js object: var obj={x:1,y:'2'}; Is this stored internally as a hashtable or does js use a different mechanism for key value pairs? If they are hash tables does anyone know how they ...
0
votes
1answer
856 views

What happens to equal elements when inserting into a binary search tree?

Most BST examples show a sample of a BST with unique values; mainly to demonstrate the order of values. e.g. values in the left subtree are smaller than the root, and values in the right subtree are ...